ROTORCRAFT FLYING HANDBOOK (2000)

RISK ELEMENTS

Pilot

Aircraft

Environment

Operation

The pilot's fitness to fly must

The aircraft's performance,

Factors, such as weather,

The purpose of the flight is a

be evaluated including

limitations, equipment, and

airport conditions, and the

factor which influences the

competency in the aircraft,

airworthiness must be deter-

availability of air traffic control

pilot's decision on undertaking

currency, and flight experience.

mined.

services must be examined.

or continuing the flight.

Situation

To maintain situational awareness, an accurate perception must be

attained of how the pilot, aircraft, environment, and operation

combine to affect the flight.

Figure 14-3. When situationally aware, you have an overview of the total operation and are not fixated on one perceived signifi-

cant factor.

landing areas, and surrounding obstacles. Weather is

RISK MANAGEMENT

one element that can change drastically over time and

During each flight, decisions must be made regarding

distance. Imagine you are ferrying a helicopter cross

events that involve interactions between the four risk

country and encounter unexpected low clouds and rain

elements-the pilot in command, the aircraft, the envi-

in an area of rising terrain. Do you try to stay under

ronment, and the operation. The decision-making

them and “scud run,” or turn around, stay in the clear,

process involves an evaluation of each of these risk ele-

and obtain current weather information?

ments to achieve an accurate perception of the flight

situation. [Figure 14-3]

Operation-The interaction between you as the pilot,

your aircraft, and the environment is greatly influenced

One of the most important decisions that a pilot in com-

by the purpose of each flight operation. You must eval-

mand must make is the go/no-go decision. Evaluating

uate the three previous areas to decide on the desirabil-

each of these risk elements can help you decide

ity of undertaking or continuing the flight as planned. It

whether a flight should be conducted or continued. Let

is worth asking yourself why the flight is being made,

us evaluate the four risk elements and how they affect

how critical is it to maintain the schedule, and is the

our decision making regarding the following situations.

trip worth the risks? For instance, you are tasked to take

some technicians into rugged mountains for a routine

Pilot-As a pilot, you must continually make decisions

survey, and the weather is marginal. Would it be prefer-

about your own competency, condition of health, mental

able to wait for better conditions to ensure a safe flight?

and emotional state, level of fatigue, and many other

How would the priorities change if you were tasked to

variables. For example, you are called early in the morn-

search for cross-country skiers who had become lost in

ing to make a long flight. You have had only a few hours

deep snow and radioed for help?

of sleep, and are concerned that the congestion you feel

could be the onset of a cold. Are you safe to fly?

ASSESSING RISK

Examining NTSB reports and other accident research

Aircraft-You will frequently base decisions on your

can help you to assess risk more effectively. For exam-

evaluations of the aircraft, such as its powerplant, per-

ple, the accident rate decreases by nearly 50 percent once

formance, equipment, fuel state, or airworthiness. Picture

a pilot obtains 100 hours, and continues to decrease until

yourself in this situation: you are en route to an oil rig an

the 1,000 hour level. The data suggest that for the first

hour’s flight from shore, and you have just passed the

500 hours, pilots flying VFR at night should establish

shoreline. Then you notice the oil temperature at the high

higher personal limitations than are required by the reg-

end of the caution range. Should you continue out to sea,

ulations and, if applicable, apply instrument flying skills

or return to the nearest suitable heliport/airport?

in this environment. [Figure 14-4]

Environment-This encompasses many elements not

Studies also indicate the types of flight activities that

pilot or aircraft related. It can include such factors as

are most likely to result in the most serious accidents.

weather, air traffic control, navaids, terrain, takeoff and

The majority of fatal general aviation accident causes

fall under the categories of maneuvering flight,

Risk Elements-The four compo-

approaches, takeoff/initial climb, and weather. Delving

nents of a flight that make up the

deeper into accident statistics can provide some impor-

overall situation.

tant details that can help you to understand the risks

NTSB-National Transportation

involved with specific flying situations. For example,

Safety Board.

maneuvering flight is one of the largest single produc-

14-4

is used when preflighting an aircraft, a personal

checklist based on such factors as experience, cur-

rency, and comfort level can help determine if you are

prepared for a particular flight. Specifying when

refresher training should be accomplished and desig-

nating weather minimums, which may be higher than

those listed in Title 14 of the Code of Federal

Regulations (14 CFR) part 91, are elements that may

be included on a personal checklist. In addition to a

review of personal limitations, you should use the I’M

SAFE Checklist to further evaluate your fitness for

flight. [Figure 14-5]

<51

101

201

501 <1000 <2000 10,000 Total

Pilot's Total Time (Hours)

I'M SAFE CHECKLIST

Figure 14-4. Statistical data can identify operations that have

more risk.

Illness-Do I have any symptoms?

ers of fatal accidents. Fatal accidents, which occur

Medication-Have I been taking prescription or

during approach, often happen at night or in IFR condi-

over-the-counter drugs?

tions. Takeoff/initial climb accidents frequently are due

to the pilot’s lack of awareness of the effects of density

Stress-Am I under psychological pressure from

altitude on aircraft performance or other improper take-

the job? Worried about financial matters, health

problems, or family discord?

off planning resulting in loss of control during, or

shortly after takeoff. The majority of weather-related

Alcohol-Have I been drinking within 8 hours?

accidents occur after attempted VFR flight into IFR

Within 24 hours?

conditions.

Fatigue-Am I tired and not adequately rested?

FACTORS AFFECTING DECISION

Eating-Am I adequately nourished?

MAKING

It is important to point out the fact that being familiar

with the decision-making process does not ensure that

you will have the good judgment to be a safe pilot. The

Figure 14-5. Prior to flight, you should assess your fitness,

ability to make effective decisions as pilot in

just as you evaluate the aircraft’s airworthiness.

command depends on a number of factors. Some

circumstances, such as the time available to make a

decision, may be beyond your control. However, you

can learn to recognize those factors that can be man-

RECOGNIZING HAZARDOUS ATTITUDES

aged, and learn skills to improve decision-making

Being fit to fly depends on more than just your physi-

ability and judgment.

cal condition and recency of experience. For example,

attitude affects the quality of your decisions. Attitude

can be defined as a personal motivational predisposi-

PILOT SELF-ASSESSMENT

tion to respond to persons, situations, or events in a

The pilot in command of an aircraft is directly responsi-

given manner. Studies have identified five hazardous

ble for, and is the final authority as to, the operation of

attitudes that can interfere with your ability to make

that aircraft. In order to effectively exercise that respon-

sound decisions and exercise authority properly.

sibility and make effective decisions regarding the

[Figure 14-6]

outcome of a flight, you must have an understanding of

your limitations. Your performance during a flight is

Hazardous attitudes can lead to poor decision making

affected by many factors, such as health, recency of

and actions that involve unnecessary risk. You must

experience, knowledge, skill level, and attitude.

examine your decisions carefully to ensure that your

choices have not been influenced by hazardous

Exercising good judgment begins prior to taking the

attitudes, and you must be familiar with positive alter-

controls of an aircraft. Often, pilots thoroughly check

natives to counteract the hazardous attitudes. These

their aircraft to determine airworthiness, yet do not

substitute attitudes are referred to as antidotes. During

evaluate their own fitness for flight. Just as a checklist

a flight operation, it is important to be able to recognize

14-5

THE FIVE HAZARDOUS ATTITUDES

1. Anti-Authority:

This attitude is found in people who do not like anyone telling them what to do. In a sense, they

"Don't tell me."

are saying, "No one can tell me what to do." They may be resentful of having someone tell them

what to do, or may regard rules, regulations, and procedures as silly or unnecessary. However, it

is always your prerogative to question authority if you feel it is in error.

2. Impulsivity:

This is the attitude of people who frequently feel the need to do something, anything, immediately.

"Do it quickly."

They do not stop to think about what they are about to do; they do not select the best alternative,

and they do the first thing that comes to mind.

3. Invulnerability:

Many people feel that accidents happen to others, but never to them. They know accidents can

"It won't happen to me."

happen, and they know that anyone can be affected. They never really feel or believe that they will

be personally involved. Pilots who think this way are more likely to take chances and increase risk.

4. Macho:

Pilots who are always trying to prove that they are better than anyone else are thinking, "I can do it

"I can do it."

-I'll show them." Pilots with this type of attitude will try to prove themselves by taking risks in order

to impress others. While this pattern is thought to be a male characteristic, women are equally

susceptible.

5. Resignation:

Pilots who think, "What's the use?" do not see themselves as being able to make a great deal of

"What's the use?"

difference in what happens to them. When things go well, the pilot is apt to think that it is good luck.

When things go badly, the pilot may feel that someone is out to get me, or attribute it to bad luck.

The pilot will leave the action to others, for better or worse. Sometimes, such pilots will even go

along with unreasonable requests just to be a "nice guy."

Figure 14-6. You should examine your decisions carefully to ensure that your choices have not been influenced by a hazardous

attitude.

a hazardous attitude, correctly label the thought, and

HAZARDOUS ATTITUDES

ANTIDOTES

then recall its antidote. [Figure 14-7]

Macho-Brenda often brags to her

Taking

friends about her skills as a pilot and

chances is

STRESS MANAGEMENT

wants to impress them with her abilities.

foolish.

Everyone is stressed to some degree all the time. A cer-

During her third solo flight she decides to

tain amount of stress is good since it keeps a person

take a friend for a helicopter ride.

alert and prevents complacency. However, effects of

Anti-authority-In the air she thinks "It's

Follow the

stress are cumulative and, if not coped with adequately,

great to be up here without an instructor

rules. They are

they eventually add up to an intolerable burden.

usually right.

criticizing everything I do. His do-it-by-the-

Performance generally increases with the onset of

book attitude takes all of the fun out of

flying."

stress, peaks, and then begins to fall off rapidly as stress

levels exceed a person’s ability to cope. The ability to

Invulnerability-As she nears her friends

It could

make effective decisions during flight can be impaired

farm, she remembers that it is about eight

happen to me.

miles from the closest airport. She thinks,

by stress. Factors, referred to as stressors, can increase

"I'll land in the pasture behind the barn at

a pilot’s risk of error in the cockpit. [Figure 14-8]

Sarah's farm. It won't be dangerous at

all... the pasture is fenced and mowed

and no animals are in the way. It's no

There are several techniques to help manage the accu-

more dangerous than landing at a

mulation of life stresses and prevent stress overload.

heliport."

For example, including relaxation time in a busy sched-

ule and maintaining a program of physical fitness can

Impulsivity-After a short look, Brenda

Not so fast.

initiates an approach to her friend's

Think first.

help reduce stress levels. Learning to manage time

pasture. Not realizing that she is landing

more effectively can help you avoid heavy pressures

with a tail wind, she makes a hard landing

imposed by getting behind schedule and not meeting

in the pasture and nearly hits the fence

deadlines. Take an assessment of yourself to determine

with the tail rotor before she gets the

helicopter stopped.

your capabilities and limitations and then set realistic

goals. In addition, avoiding stressful situations and

Resignation-A policeman pulls up to

I'm not

encounters can help you cope with stress.

investigate what he believes to be an

helpless. I can

emergency landing. As Brenda is walking

make a

from the helicopter, she is supprised that

difference.

USE OF RESOURCES

anyone observed her landing. Her first

To make informed decisions during flight operations,

thought is "if it weren't for my bad luck, this

policeman wouldn't have come along and

you must be aware of the resources found both inside

this would have been a great afternoon."

and outside the cockpit. Since useful tools and sources

of information may not always be readily apparent,

Figure 14-7. You must be able to identify hazardous attitudes

learning to recognize these resources is an essential

and apply the appropriate antidote when needed.

part of ADM training. Resources must not only be iden-

14-6

STRESSORS

Physical Stress-Conditions associated with the environment, such as temperature and

humidity extremes, noise, vibration, and lack of oxygen.

Physiological Stress-Physical conditions, such as fatigue, lack of physical fitness, sleep

loss, missed meals (leading to low blood sugar levels), and illness.

Psychological Stress-Social or emotional factors, such as a death in the family, a divorce, a

sick child, or a demotion at work. This type of stress may also be related to mental workload,

such as analyzing a problem, navigating an aircraft, or making decisions.

Figure 14-8. The three types of stressors that can affect a pilot’s performance.

tified, but you must develop the skills to evaluate

information in an irregular situation, especially if they

whether you have the time to use a particular resource

are familiar with flying. A strange smell or sound may

and the impact that its use will have upon the safety of

alert a passenger to a potential problem. As pilot in

flight. For example, the assistance of ATC may be very

command, you should brief passengers before the

useful if you are lost. However, in an emergency situa-

flight to make sure that they are comfortable voicing

tion when action needs be taken quickly, time may not

any concerns.

be available to contact ATC immediately.

EXTERNAL RESOURCES

INTERNAL RESOURCES

Possibly the greatest external resources during flight

Internal resources are found in the cockpit during

are air traffic controllers and flight service specialists.

flight. Since some of the most valuable internal

ATC can help decrease pilot workload by providing

resources are ingenuity, knowledge, and skill, you can

traffic advisories, radar vectors, and assistance in emer-

expand cockpit resources immensely by improving

gency situations. Flight service stations can provide

these capabilities. This can be accomplished by fre-

updates on weather, answer questions about airport

quently reviewing flight information publications, such

conditions, and may offer direction-finding assistance.

as the CFRs and the AIM, as well as by pursuing addi-

The services provided by ATC can be invaluable in

tional training.

enabling you to make informed in-flight decisions.

A thorough understanding of all the equipment and sys-

WORKLOAD MANAGEMENT

tems in the aircraft is necessary to fully utilize all

Effective workload management ensures that essential

resources. For example, advanced navigation and

operations are accomplished by planning, prioritizing,

autopilot systems are valuable resources. However, if

and sequencing tasks to avoid work overload. As

pilots do not fully understand how to use this equip-

experience is gained, you learn to recognize future

ment, or they rely on it so much that they become

workload requirements and can prepare for high

complacent, it can become a detriment to safe flight.

workload periods during times of low workload.

Reviewing the appropriate chart and setting radio fre-

Checklists are essential cockpit resources for verifying

quencies well in advance of when they are needed

that the aircraft instruments and systems are checked,

helps reduce workload as your flight nears the airport.

set, and operating properly, as well as ensuring that the

In addition, you should listen to ATIS, ASOS, or

proper procedures are performed if there is a system

AWOS, if available, and then monitor the tower fre-

malfunction or in-flight emergency. In addition, the

quency or CTAF to get a good idea of what traffic

FAA-approved rotorcraft flight manual, which is

conditions to expect. Checklists should be performed

required to be carried on board the aircraft, is essential

well in advance so there is time to focus on traffic and

for accurate flight planning and for resolving in-flight

ATC instructions. These procedures are especially

equipment malfunctions. Other valuable cockpit

important prior to entering a high-density traffic area,

resources include current aeronautical charts, and pub-

such as Class B airspace.

lications, such as the Airport/Facility Directory.

To manage workload, items should be prioritized. For

example, during any situation, and especially in an

Passengers can also be a valuable resource. Passengers

emergency, you should remember the phrase “aviate,

can help watch for traffic and may be able to provide

14-7

navigate, and communicate.” This means that the first

of the environmental conditions of the flight, such as

thing you should do is make sure the helicopter is under

spatial orientation of the helicopter, and its relation-

ship to terrain, traffic, weather, and airspace must be

maintained.

Pilot Capabilities

To maintain situational awareness, all of the skills

involved in aeronautical decision making are used. For

Margin

example, an accurate perception of your fitness can be

of Safety

achieved through self-assessment and recognition of

hazardous attitudes. A clear assessment of the status of

navigation equipment can be obtained through work-

Task

load management, and establishing a productive

Requirements

relationship with ATC can be accomplished by effec-

Time

tive resource use.

Preflight

Taxi

Takeoff

Cruise

Approach &

Taxi

Landing

OBSTACLES TO MAINTAINING SITUATIONAL

Figure 14-9. Accidents often occur when flying task require-

AWARENESS

ments exceed pilot capabilities. The difference between

Fatigue, stress, and work overload can cause you to fix-

these two factors is called the margin of safety. Note that in

this idealized example, the margin of safety is minimal during

ate on a single perceived important item rather than

the approach and landing. At this point, an emergency or dis-

maintaining an overall awareness of the flight situa-

traction could overtax pilot capabilities, causing an accident.

tion. A contributing factor in many accidents is a

distraction that diverts the pilot’s attention from moni-

toring the instruments or scanning outside the

control. Then begin flying to an acceptable landing

aircraft. Many cockpit distractions begin as a minor

area. Only after the first two items are assured, should

problem, such as a gauge that is not reading correctly,

you try to communicate with anyone.

but result in accidents as the pilot diverts attention to

the perceived problem and neglects to properly control

Another important part of managing workload is rec-

the aircraft.

ognizing a work overload situation. The first effect of

high workload is that you begin to work faster. As

Complacency presents another obstacle to maintaining

workload increases, attention cannot be devoted to sev-

situational awareness. When activities become routine,

eral tasks at one time, and you may begin to focus on

you may have a tendency to relax and not put as much

one item. When you become task saturated, there is no

effort into performance. Like fatigue, complacency

awareness of inputs from various sources, so decisions

reduces your effectiveness in the cockpit. However,

may be made on incomplete information, and the pos-

complacency is harder to recognize than fatigue, since

sibility of error increases. [Figure 14-9]

everything is perceived to be progressing smoothly. For

example, you have just dropped off another group of

When becoming overloaded, you should stop, think,

fire fighters for the fifth time that day. Without think-

slow down, and prioritize. It is important that you

ing, you hastily lift the helicopter off the ground, not

understand options that may be available to decrease

realizing that one of the skids is stuck between two

workload. For example, tasks, such as locating an item

rocks. The result is dynamic rollover and a destroyed

on a chart or setting a radio frequency, may be dele-

helicopter.

gated to another pilot or passenger, an autopilot, if

available, may be used, or ATC may be enlisted to

provide assistance.

OPERATIONAL PITFALLS

There are a number of classic behavioral traps into

SITUATIONAL AWARENESS

which pilots have been known to fall. Pilots, particu-

Situational awareness is the accurate perception of the

larly those with considerable experience, as a rule,

operational and environmental factors that affect the

always try to complete a flight as planned, please pas-

aircraft, pilot, and passengers during a specific period

sengers, and meet schedules. The basic drive to meet

of time. Maintaining situational awareness requires

or exceed goals can have an adverse effect on safety,

an understanding of the relative significance of these

and can impose an unrealistic assessment of piloting

factors and their future impact on the flight. When sit-

skills under stressful conditions. These tendencies ulti-

uationally aware, you have an overview of the total

mately may bring about practices that are dangerous

operation and are not fixated on one perceived signif-

and often illegal, and may lead to a mishap. You will

icant factor. Some of the elements inside the aircraft

develop awareness and learn to avoid many of these

to be considered are the status of aircraft systems, you

operational pitfalls through effective ADM training.

as the pilot, and passengers. In addition, an awareness

[Figure 14-10]

14-8

OPERATIONAL PITFALLS

Peer Pressure-Poor decision making may be based upon an emotional response to peers, rather than evaluating a situation

objectively.

Mind Set-A pilot displays mind set through an inability to recognize and cope with changes in a given situation.

Get-There-Itis-This disposition impairs pilot judgment through a fixation on the original goal or destination, combined with a

disregard for any alternative course of action.

Scud Running-This occurs when a pilot tries to maintain visual contact with the terrain at low altitudes while instrument

conditions exist.

Continuing Visual Flight Rules (VFR) into Instrument Conditions-Spatial disorientation or collision with ground/obstacles

may occur when a pilot continues VFR into instrument conditions. This can be even more dangerous if the pilot is not

instrument-rated or current.

Getting Behind the Aircraft-This pitfall can be caused by allowing events or the situation to control pilot actions. A constant

state of surprise at what happens next may be exhibited when the pilot is getting behind the aircraft.

Loss of Positional or Situational Awareness-In extreme cases, when a pilot gets behind the aircraft, a loss of positional or

situational awareness may result. The pilot may not know the aircraft's geographical location, or may be unable to recognize

deteriorating circumstances.

Operating Without Adequate Fuel Reserves-Ignoring minimum fuel reserve requirements is generally the result of

overconfidence, lack of flight planning, or disregarding applicable regulations.

Flying Outside the Envelope-The assumed high performance capability of a particular aircraft may cause a mistaken belief

that it can meet the demands imposed by a pilot's overestimated flying skills.

Neglect of Flight Planning, Preflight Inspections, and Checklists-A pilot may rely on short- and long-term memory,

regular flying skills, and familiar routes instead of established procedures and published checklists. This can be particularly true

of experienced pilots.

Figure 14-10. All experienced pilots have fallen prey to, or have been tempted by, one or more of these tendencies in their flying

careers.

14-9

autorotation. The first successful example of this type

January 9th, 1923, marked the first officially observed

of aircraft was the British Fairy Rotodyne, certificated

flight of an autogyro. The aircraft, designed by Juan de

to the Transport Category in 1958. During the 1960s

la Cierva, introduced rotor technology that made for-

and 1970s, the popularity of gyroplanes increased with

ward flight in a rotorcraft possible. Until that time,

the certification of the McCulloch J-2 and Umbaugh.

rotary-wing aircraft designers were stymied by the

The latter becoming the Air & Space 18A.

problem of a rolling moment that was encountered

when the aircraft began to move forward. This rolling

There are several aircraft under development using the

moment was the product of airflow over the rotor disc,

free spinning rotor to achieve rotary wing takeoff per-

causing an increase in lift of the advancing blade and

formance and fixed wing cruise speeds. The gyroplane

decrease in lift of the retreating blade. Cierva’s success-

offers inherent safety, simplicity of operation, and out-

ful design, the C.4, introduced the articulated rotor, on

standing short field point-to-point capability.

which the blades were hinged and allowed to flap. This

solution allowed the advancing blade to move upward,

decreasing angle of attack and lift, while the retreating

TYPES OF GYROPLANES

blade would swing downward, increasing angle of

Because the free spinning rotor does not require an

attack and lift. The result was balanced lift across the

antitorque device, a single rotor is the predominate

rotor disc regardless of airflow. This breakthrough was

configuration. Counter-rotating blades do not offer

instrumental in the success of the modern helicopter,

any particular advantage. The rotor system used in a

which was developed over 15 years later. (For more

gyroplane may have any number of blades, but the

information on dissymmetry of lift, refer to Chapter 3-

most popular are the two and three blade systems.

Aerodynamics of Flight.) On April 2, 1931, the Pitcairn

Propulsion for gyroplanes may be either tractor or

PCA-2 autogyro was granted Type Certificate No. 410

pusher, meaning the engine may be mounted on the

and became the first rotary wing aircraft to be certified

front and pull the aircraft, or in the rear, pushing it

in the United States. The term “autogyro” was used to

through the air. The powerplant itself may be either

describe this type of aircraft until the FAA later desig-

reciprocating or turbine. Early gyroplanes were

nated them “gyroplanes.”

often a derivative of tractor configured airplanes

with the rotor either replacing the wing or acting in

By definition, the gyroplane is an aircraft that achieves

conjunction with it. However, the pusher configura-

lift by a free spinning rotor. Several aircraft have used

tion is generally more maneuverable due to the

the free spinning rotor to attain performance not avail-

placement of the rudder in the propeller slipstream,

able in the pure helicopter. The “gyrodyne” is a hybrid

and also has the advantage of better visibility for the

rotorcraft that is capable of hovering and yet cruises in

pilot. [Figure 15-1]

Figure 15-1. The gyroplane may have wings, be either tractor or pusher configured, and could be turbine or propeller powered.

Pictured are the Pitcairn PCA-2 Autogyro (left) and the Air & Space 18A gyroplane.

15-1

When direct control of the rotor head was perfected,

the welded tube structure, which has been in use for a

the jump takeoff gyroplane was developed. Under the

number of years.

proper conditions, these gyroplanes have the ability to

lift off vertically and transition to forward flight. Later

POWERPLANT

developments have included retaining the direct con-

The powerplant provides the thrust necessary for forward

trol rotor head and utilizing a wing to unload the rotor,

flight, and is independent of the rotor system while in

which results in increased forward speed.

flight. While on the ground, the engine may be used as

a source of power to prerotate the rotor system. Over

COMPONENTS

the many years of gyroplane development, a wide

Although gyroplanes are designed in a variety of config-

variety of engine types have been adapted to the gyro-

urations, for the most part the basic components are the

plane. Automotive, marine, ATV, and certificated

same. The minimum components required for a func-

aircraft engines have all been used in various

tional gyroplane are an airframe, a powerplant, a rotor

gyroplane designs. Certificated gyroplanes are

system, tail surfaces, and landing gear. [Figure 15-2] An

required to use FAA certificated engines. The cost of a

optional component is the wing, which is incorporated

new certificated aircraft engine is greater than the cost

into some designs for specific performance objectives.

of nearly any other new engine. This added cost is the

primary reason other types of engines are selected for

use in amateur built gyroplanes.

ROTOR SYSTEM

The rotor system provides lift and control for the gyro-

Rotor

plane. The fully articulated and semi-rigid teetering

rotor systems are the most common. These are

explained in-depth in Chapter 5-Main Rotor System.

The teeter blade with hub tilt control is most common

Tail

in homebuilt gyroplanes. This system may also employ

Surfaces

a collective control to change the pitch of the rotor

blades. With sufficient blade inertia and collective

pitch change, jump takeoffs can be accomplished.

Airframe

TAIL SURFACES

The tail surfaces provide stability and control in the pitch

Powerplant

and yaw axes. These tail surfaces are similar to an air-

plane empennage and may be comprised of a fin and

rudder, stabilizer and elevator. An aft mounted duct

Landing Gear

enclosing the propeller and rudder has also been used.

Many gyroplanes do not incorporate a horizontal tail

surface.

Figure 15-2. Gyroplanes typically consist of five major com-

ponents. A sixth, the wing, is utilized on some designs.

On some gyroplanes, especially those with an enclosed

cockpit, the yaw stability is marginal due to the large

AIRFRAME

fuselage side area located ahead of the center of grav-

The airframe provides the structure to which all other

ity. The additional vertical tail surface necessary to

components are attached. Airframes may be welded

compensate for this instability is difficult to achieve as

tube, sheet metal, composite, or simply tubes bolted

the confines of the rotor tilt and high landing pitch atti-

together. A combination of construction methods may

tude limits the available area. Some gyroplane designs

also be employed. The airframes with the greatest

incorporate multiple vertical stabilizers and rudders to

strength-to-weight ratios are a carbon fiber material or

add additional yaw stability.

Direct Control-The capacity for

Unload-To reduce the compo-

Prerotate-Spinning a gyroplane

the pilot to maneuver the aircraft

nent of weight supported by the

rotor to sufficient r.p.m. prior to

by tilting the rotor disc and, on

rotor system.

flight.

some gyroplanes, affect changes in

pitch to the rotor blades. These

equate to cyclic and collective con-

trol, which were not available in

earlier autogyros.

15-2

Helicopters and gyroplanes both achieve lift through

for a given flight condition. The other component is the

the use of airfoils, and, therefore, many of the basic

rotational airflow, which is the wind velocity across the

aerodynamic principles governing the production of lift

blades as they spin. This component varies signifi-

apply to both aircraft. These concepts are explained in

cantly based upon how far from the rotor hub it is

depth in Chapter 2-General Aerodynamics, and con-

measured. For example, consider a rotor disc that is 25

stitute the foundation for discussing the aerodynamics

feet in diameter operating at 300 r.p.m. At a point one

of a gyroplane.

foot outboard from the rotor hub, the blades are travel-

ing in a circle with a circumference of 6.3 feet. This

AUTOROTATION

equates to 31.4 feet per second (f.p.s.), or a rotational

A fundamental difference between helicopters and

blade speed of 21 m.p.h. At the blade tips, the circum-

gyroplanes is that in powered flight, a gyroplane rotor

ference of the circle increases to 78.5 feet. At the same

system operates in autorotation. This means the rotor

operating speed of 300 r.p.m., this creates a blade tip

spins freely as a result of air flowing up through the

blades, rather than using engine power to turn the

blades and draw air from above. [Figure 16-1] Forces

are created during autorotation that keep the rotor

blades turning, as well as creating lift to keep the air-

craft aloft. Aerodynamically, the rotor system of a

Upward

gyroplane in normal flight operates like a helicopter

Airflow

rotor during an engine-out forward autorotative

descent.

Wind due to Blade Rotation

VERTICAL AUTOROTATION

During a vertical autorotation, two basic components

contribute to the relative wind striking the rotor blades.

Figure 16-2. In a vertical autorotation, the wind from the

[Figure 16-2] One component, the upward flow of air

rotation of the blade combines with the upward airflow to

through the rotor system, remains relatively constant

produce the resultant relative wind striking the airfoil.

Relative Wind

Direction of Flight

Figure 16-1. Airflow through the rotor system on a gyroplane is reversed from that on a powered helicopter. This airflow is the

medium through which power is transferred from the gyroplane engine to the rotor system to keep it rotating.

16-1

VERTICAL AUTOROTATION

HUB

Upward Airflow

(17 m.p.h. or 25 f.p.s.)

Rotational Airflow

(21 m.p.h. or 31 f.p.s.)

Rotor Speed: 300 r.p.m.

TIP

Upward Airflow

(17 m.p.h. or 25 f.p.s.)

Rotational Airflow (267 m.p.h. or 393 f.p.s.)

Figure 16-3. Moving outboard on the rotor blade, the rotational velocity increasingly exceeds the upward component of airflow,

resulting in a higher relative wind at a lower angle of attack.

speed of 393 feet per second, or 267 m.p.h. The result

is a higher total relative wind, striking the blades at a

VERTICAL AUTOROTATION

lower angle of attack. [Figure 16-3]

ROTOR DISC REGIONS

Driven Region

As with any airfoil, the lift that is created by rotor

blades is perpendicular to the relative wind. Because

Driving Region

the relative wind on rotor blades in autorotation shifts

from a high angle of attack inboard to a lower angle of

Stall

attack outboard, the lift generated has a higher forward

component closer to the hub and a higher vertical com-

Region

ponent toward the blade tips. This creates distinct

regions of the rotor disc that create the forces neces-

sary for flight in autorotation. [Figure 16-4] The

autorotative region, or driving region, creates a total

aerodynamic force with a forward component that

exceeds all rearward drag forces and keeps the blades

spinning. The propeller region, or driven region, gen-

Driven Region

Driving Region

Stall Region

erates a total aerodynamic force with a higher vertical

(Propeller)

(Autorotative)

component that allows the gyroplane to remain aloft.

Total

(Blade is Stalled)

Near the center of the rotor disc is a stall region where

Aerodynamic

TAF

Force Aft

Force

the rotational component of the relative wind is so low

Lift

of Axis of

TAF

Forward

Rotation

Lift

of Axis of

that the resulting angle of attack is beyond the stall

Rotational

Rotation

Relative Wind

Lift

TAF

Drag

limit of the airfoil. The stall region creates drag against

Drag

the direction of rotation that must be overcome by the

Inflow Up

Chord Line

Through Rotor

Inflow

forward acting forces generated by the driving region.

Resultant

Inflow

Relative Wind

Axis of

Rotation

AUTOROTATION IN FORWARD FLIGHT

As discussed thus far, the aerodynamics of autorotation

Figure 16-4. The total aerodynamic force is aft of the axis of

rotation in the driven region and forward of the axis of rota-

apply to a gyroplane in a vertical descent. Because

tion in the driving region. Drag is the major aerodynamic

gyroplanes are normally operated in forward flight, the

force in the stall region. For a complete depiction of force

component of relative wind striking the rotor blades as

vectors during a vertical autorotation, refer to Chapter 3-

a result of forward speed must also be considered. This

Aerodynamics of Flight (Helicopter), Figure 3-22.

component has no effect on the aerodynamic principles

that cause the blades to autorotate, but causes a shift in

As a gyroplane moves forward through the air, the for-

the zones of the rotor disc.

ward speed of the aircraft is effectively added to the

16-2

relative wind striking the advancing blade, and sub-

rily on the forward speed of the aircraft, with higher

tracted from the relative wind striking the retreating

speed creating a larger region of reverse flow. To some

blade. To prevent uneven lifting forces on the two sides

degree, the operating speed of the rotor system also has

of the rotor disc, the advancing blade teeters up,

an effect on the size of the region, with systems operat-

decreasing angle of attack and lift, while the retreating

ing at lower r.p.m. being more susceptible to reverse

blade teeters down, increasing angle of attack and lift.

flow and allowing a greater portion of the blade to

(For a complete discussion on dissymmetry of lift, refer

experience the effect.

to Chapter 3-Aerodynamics of Flight.) The lower

angles of attack on the advancing blade cause more of

the blade to fall in the driven region, while higher

angles of attack on the retreating blade cause more of

Forward

the blade to be stalled. The result is a shift in the rotor

Flight at

regions toward the retreating side of the disc to a degree

42 kt

directly related to the forward speed of the aircraft.

[Figure 16-5]

Forward

Retreating

Driven Region

Advancing

Side

Area of

Driving Region

Reverse flow

Stall

Region

Rotor Speed 300 r.p.m.

Figure 16-6. An area of reverse flow forms on the retreating

blade in forward flight as a result of aircraft speed exceeding

blade rotational speed.

Figure 16-5. Rotor disc regions in forward autorotative flight.

RETREATING BLADE STALL

The retreating blade stall in a gyroplane differs from

REVERSE FLOW

that of a helicopter in that it occurs outboard from the

On a rotor system in forward flight, reverse flow occurs

rotor hub at the 20 to 40 percent position rather than at

near the rotor hub on the retreating side of the rotor

the blade tip. Because the gyroplane is operating in

disc. This is the result of the forward speed of the air-

autorotation, in forward flight there is an inherent stall

craft exceeding the rotational speed of the rotor blades.

region centered inboard on the retreating blade. [Refer

For example, two feet outboard from the rotor hub, the

to figure 16-5] As forward speed increases, the angle of

blades travel in a circle with a circumference of 12.6

attack on the retreating blade increases to prevent dis-

feet. At a rotor speed of 300 r.p.m., the blade speed at

symmetry of lift and the stall region moves further

the two-foot station is 42 m.p.h. If the aircraft is being

outboard on the retreating blade. Because the stalled

operated at a forward speed of 42 m.p.h., the forward

portion of the rotor disc is inboard rather than near the

speed of the aircraft essentially negates the rotational

tip, as with a helicopter, less force is created about the

velocity on the retreating blade at the two-foot station.

aircraft center of gravity. The result is that you may feel

Moving inboard from the two-foot station on the

a slight increase in vibration, but you would not experi-

retreating blade, the forward speed of the aircraft

ence a large pitch or roll tendency.

increasingly exceeds the rotational velocity of the

blade. This causes the airflow to actually strike the

ROTOR FORCE

trailing edge of the rotor blade, with velocity increas-

As with any heavier than air aircraft, the four forces

ing toward the rotor hub. [Figure 16-6] The size of the

acting on the gyroplane in flight are lift, weight, thrust

area that experiences reverse flow is dependent prima-

and drag. The gyroplane derives lift from the rotor and

16-3

Rotor

Thrust

Drag

Thrust

Fuselage

Drag

Figure 16-7. Unlike a helicopter, in forward powered flight the resultant rotor force of a gyroplane acts in a rearward direction.

thrust directly from the engine through a propeller.

rotor blades turn, rapid changes occur on the airfoils

[Figure 16-7]

depending on position, rotor speed, and aircraft speed.

A change in the angle of attack of the rotor disc can

The force produced by the gyroplane rotor may be

effect a rapid and substantial change in total rotor drag.

divided into two components; rotor lift and rotor drag.

The component of rotor force perpendicular to the

Rotor drag can be divided into components of induced

flight path is rotor lift, and the component of rotor force

drag and profile drag. The induced drag is a product of

parallel to the flight path is rotor drag. To derive the

lift, while the profile drag is a function of rotor r.p.m.

total aircraft drag reaction, you must also add the drag

Because induced drag is a result of the rotor providing

of the fuselage to that of the rotor.

lift, profile drag can be considered the drag of the rotor

when it is not producing lift. To visualize profile drag,

ROTOR LIFT

consider the drag that must be overcome to prerotate

Rotor lift can most easily be visualized as the lift

the rotor system to flight r.p.m. while the blades are

required to support the weight of the aircraft. When an

producing no lift. This can be achieved with a rotor sys-

airfoil produces lift, induced drag is produced. The

tem having a symmetrical airfoil and a pitch change

most efficient angle of attack for a given airfoil pro-

capability by setting the blades to a 0° angle of attack.

duces the most lift for the least drag. However, the air-

A rotor system with an asymmetrical airfoil and a built

foil of a rotor blade does not operate at this efficient

in pitch angle, which includes most amateur-built

angle throughout the many changes that occur in each

teeter-head rotor systems, cannot be prerotated without

revolution. Also, the rotor system must remain in the

having to overcome the induced drag created as well.

autorotative (low) pitch range to continue turning in

order to generate lift.

THRUST

Thrust in a gyroplane is defined as the component of

Some gyroplanes use small wings for creating lift when

total propeller force parallel to the relative wind. As

operating at higher cruise speeds. The lift provided by

with any force applied to an aircraft, thrust acts around

the wings can either supplement or entirely replace

the center of gravity. Based upon where the thrust is

rotor lift while creating much less induced drag.

applied in relation to the aircraft center of gravity, a rel-

atively small component may be perpendicular to the

ROTOR DRAG

relative wind and can be considered to be additive to

Total rotor drag is the summation of all the drag forces

lift or weight.

acting on the airfoil at each blade position. Each blade

position contributes to the total drag according to the

In flight, the fuselage of a gyroplane essentially acts as

speed and angle of the airfoil at that position. As the

a plumb suspended from the rotor, and as such, it is

16-4

subject to pendular action in the same way as a heli-

There are several factors that contribute to the stability

copter. Unlike a helicopter, however, thrust is applied

of a gyroplane. One is the location of the horizontal

directly to the airframe of a gyroplane rather than being

stabilizer. Another is the location of the fuselage drag

obtained through the rotor system. As a result, different

in relation to the center of gravity. A third is the

forces act on a gyroplane in flight than on a helicopter.

inertia moment around the pitch axis, while a fourth is

Engine torque, for example, tends to roll the fuselage

the relation of the propeller thrust line to the vertical

in the direction opposite propeller rotation, causing it

location of the center of gravity (CG). However, the

to be deflected a few degrees out of the vertical plane.

one that is probably the most critical is the relation of

[Figure 16-8] This slight “out of vertical” condition is

the rotor force line to the horizontal location of the

usually negligible and not considered relevant for most

center of gravity.

flight operations.

HORIZONTAL STABILIZER

A horizontal stabilizer helps in longitudinal stability,

with its efficiency greater the further it is from the

center of gravity. It is also more efficient at higher

airspeeds because lift is proportional to the square of

Torque

the airspeed. Since the speed of a gyroplane is not very

Applied to

Prop

eller

high, manufacturers can achieve the desired stability

by varying the size of the horizontal stabilizer, chang-

ing the distance it is from the center of gravity, or by

placing it in the propeller slipstream.

FUSELAGE DRAG

eactive

(CENTER OF PRESSURE)

Torque on

If the location, where the fuselage drag or center of

Fuselage

pressure forces are concentrated, is behind the CG,

the gyroplane is considered more stable. This is espe-

Figure 16-8. Engine torque applied to the propeller has an

cially true of yaw stability around the vertical axis.

equal and opposite reaction on the fuselage, deflecting it a

However, to achieve this condition, there must be a

few degrees out of the vertical plane in flight.

sufficient vertical tail surface. In addition, the gyro-

plane needs to have a balanced longitudinal center of

pressure so there is sufficient cyclic movement to

prevent the nose from tucking under or lifting, as

STABILITY

pressure builds on the frontal area of the gyroplane as

Stability is designed into aircraft to reduce pilot work-

airspeed increases.

load and increase safety. A stable aircraft, such as a typ-

ical general aviation training airplane, requires less

attention from the pilot to maintain the desired flight

PITCH INERTIA

attitude, and will even correct itself if disturbed by a

Without changing the overall weight and center of

gust of wind or other outside forces. Conversely, an

gravity of a gyroplane, the further weights are placed

unstable aircraft requires constant attention to maintain

from the CG, the more stable the gyroplane. For exam-

control of the aircraft.

ple, if the pilot's seat could be moved forward from the

CG, and the engine moved aft an amount, which keeps

the center of gravity in the same location, the gyroplane

becomes more stable. A tightrope walker applies this

same principle when he uses a long pole to balance

himself.

PROPELLER THRUST LINE

Pendular Action-The lateral or

Considering just the propeller thrust line by itself, if the

longitudinal oscillation of the fuse-

thrust line is above the center of gravity, the gyroplane

lage due to it being suspended

from the rotor system. It is similar

has a tendency to pitch nose down when power is

to the action of a pendulum.

applied, and to pitch nose up when power is removed.

Pendular action is further dis-

cussed in Chapter 3-

The opposite is true when the propeller thrust line is

Aerodynamics of Flight.

below the CG. If the thrust line goes through the CG or

16-5

Low Profile

High Profile

Propeller Thrust

Center of Gravity

Figure 16-9. A gyroplane which has the propeller thrust line above the center of gravity is often referred to as a low profile gyro-

plane. One that has the propeller thrust line below or at the CG is considered a high profile gyroplane.

nearly so there is no tendency for the nose to pitch up

TRIMMED CONDITION

or down. [Figure 16-9]

As was stated earlier, manufacturers use a combination

of the various stability factors to achieve a trimmed

ROTOR FORCE

gyroplane. For example, if you have a gyroplane where

Because some gyroplanes do not have horizontal stabi-

the CG is below the propeller thrust line, the propeller

lizers, and the propeller thrust lines are different, gyro-

thrust gives your aircraft a nose down pitching moment

plane manufacturers can achieve the desired stability

when power is applied. To compensate for this pitching

by placing the center of gravity in front of or behind the

moment, the CG, on this type of gyroplane, is usually

rotor force line. [Figure 16-10]

located behind the rotor force line. This location pro-

duces a nose up pitching moment.

Suppose the CG is located behind the rotor force line in

forward flight. If a gust of wind increases the angle of

Conversely, if the CG is above the propeller thrust line,

attack, rotor force increases. There is also an increase

the CG is usually located ahead of the rotor force line.

in the difference between the lift produced on the

Of course, the location of fuselage drag, the pitch iner-

advancing and retreating blades. This increases the

tia, and the addition of a horizontal stabilizer can alter

flapping angle and causes the rotor to pitch up. This

where the center of gravity is placed.

pitching action increases the moment around the center

of gravity, which leads to a greater increase in the angle

of attack. The result is an unstable condition.

If the CG is in front of the rotor force line, a gust of

wind, which increases the angle of attack, causes the

rotor disc to react the same way, but now the increase

in rotor force and blade flapping decreases the

Blade Flapping-The upward or downward movement of the rotor-

moment. This tends to decrease the angle of attack, and

blades during rotation.

creates a stable condition.

Figure 16-10. If the CG is located in front of the rotor force line, the gyroplane is more stable than if the CG is located behind the

rotor force line.

16-6

Due to rudimentary flight control systems, early gyroplanes

suffered from limited maneuverability. As technology

improved, greater control of the rotor system and more

effective control surfaces were developed. The modern

gyroplane, while continuing to maintain an element of

simplicity, now enjoys a high degree of maneuver-

ability as a result of these improvements.

CYCLIC CONTROL

The cyclic control provides the means whereby you are

able to tilt the rotor system to provide the desired

results. Tilting the rotor system provides all control for

climbing, descending, and banking the gyroplane. The

most common method to transfer stick movement to

the rotor head is through push-pull tubes or flex cables.

[Figure 17-1] Some gyroplanes use a direct overhead

stick attachment rather than a cyclic, where a rigid con-

trol is attached to the rotor hub and descends over and

in front of the pilot. [Figure 17-2] Because of the

nature of the direct attachment, control inputs with this

system are reversed from those used with a cyclic.

Pushing forward on the control causes the rotor disc to

tilt back and the gyroplane to climb, pulling back on

Figure 17-2. The direct overhead stick attachment has been

the control initiates a descent. Bank commands are

used for control of the rotor disc on some gyroplanes.

reversed in the same way.

the control is designed, control movement may or

THROTTLE

may not be proportional to engine power. With many

The throttle is conventional to most powerplants, and

gyroplane throttles, 50 percent of the control travel

provides the means for you to increase or decrease

may equate to 80 or 90 percent of available power.

engine power and thus, thrust. Depending on how

This varying degree of sensitivity makes it necessary

Figure 17-1. A common method of transferring cyclic control inputs to the rotor head is through the use of push-pull tubes,

located outboard of the rotor mast pictured on the right.

17-1

Figure 17-3. Foot pedals provide rudder control and operation is similar to that of an airplane.

for you to become familiar with the unique throttle

stabilizers, are incorporated into gyroplane designs to

characteristics and engine responses for a particular

increase the pitch stability of the aircraft. Some gyro-

gyroplane.

planes use very little, if any, horizontal surface. This

translates into less stability, but a higher degree of

RUDDER

maneuverability. When used, a moveable horizontal

The rudder is operated by foot pedals in the cockpit

surface, or elevator, adds additional pitch control of the

and provides a means to control yaw movement of the

aircraft. On early tractor configured gyroplanes, the

aircraft. [Figure 17-3] On a gyroplane, this control is

elevator served an additional function of deflecting the

achieved in a manner more similar to the rudder of an

propeller slipstream up and through the rotor to assist

airplane than to the antitorque pedals of a helicopter.

in prerotation.

The rudder is used to maintain coordinated flight, and

at times may also require inputs to compensate for

COLLECTIVE CONTROL

propeller torque. Rudder sensitivity and effectiveness

The collective control provides a means to vary the

are directly proportional to the velocity of airflow over

rotor blade pitch of all the blades at the same time, and

the rudder surface. Consequently, many gyroplane

is available only on more advanced gyroplanes. When

rudders are located in the propeller slipstream and

incorporated into the rotor head design, the collective

provide excellent control while the engine is developing

allows jump takeoffs when the blade inertia is suffi-

thrust. This type of rudder configuration, however, is

cient. Also, control of in-flight rotor r.p.m. is available

less effective and requires greater deflection when the

to enhance cruise and landing performance. A simple

engine is idled or stopped.

two position collective does not allow unlimited control

of blade pitch, but instead has one position for prerotation

HORIZONTAL TAIL SURFACES

and another position for flight. This is a performance

The horizontal tail surfaces on most gyroplanes are

compromise but reduces pilot workload by simplifying

not controllable by the pilot. These fixed surfaces, or

control of the rotor system.

17-2

Gyroplanes are available in a wide variety of designs

rotating portion of the head to the non-rotating torque

that range from amateur built to FAA-certificated air-

tube. The torque tube is mounted to the airframe

craft. Similarly, the complexity of the systems inte-

through attachments allowing both lateral and longitu-

grated in gyroplane design cover a broad range. To

dinal movement. This allows the movement through

ensure the airworthiness of your aircraft, it is important

which control is achieved.

that you thoroughly understand the design and opera-

tion of each system employed by your machine.

Tower Plates

Teeter Bolt

PROPULSION SYSTEMS

Most of the gyroplanes flying today use a reciprocating

Tower Block

engine mounted in a pusher configuration that drives

either a fixed or constant speed propeller. The engines

Hub Bar

used in amateur-built gyroplanes are normally proven

Spindle Bolt

powerplants adapted from automotive or other uses.

Some amateur-built gyroplanes use FAA-certificated air-

craft engines and propellers. Auto engines, along with

some of the other powerplants adapted to gyroplanes,

Bearing Block

operate at a high r.p.m., which requires the use of a reduc-

tion unit to lower the output to efficient propeller speeds.

Torque Tube

Early autogyros used existing aircraft engines, which

Fore / Aft Pivot Bolt

drove a propeller in the tractor configuration. Several

amateur-built gyroplanes still use this propulsion con-

Lateral Pivot Bolt

figuration, and may utilize a certificated or an uncer-

tificated engine. Although not in use today, turboprop

and pure jet engines could also be used for the propul-

sion of a gyroplane.

Figure 18-1. The semirigid, teeter-head system is found on

most amateur-built gyroplanes. The rotor hub bar and blades

ROTOR SYSTEMS

are permitted to tilt by the teeter bolt.

SEMIRIGID ROTOR SYSTEM

Any rotor system capable of autorotation may be utilized

in a gyroplane. Because of its simplicity, the most widely

FULLY ARTICULATED ROTOR SYSTEM

used system is the semirigid, teeter-head system. This

The fully articulated rotor system is found on some

system is found in most amateur-built gyroplanes.

gyroplanes. As with helicopter-type rotor systems, the

[Figure 18-1] In this system, the rotor head is mounted

articulated rotor system allows the manipulation of

on a spindle, which may be tilted for control. The rotor

blades are attached to a hub bar that may or may not

have adjustments for varying the blade pitch. Aconing

angle, determined by projections of blade weight,

Coning Angle-An angular

Undersling-A design character-

rotor speed, and load to be carried, is built into the hub

deflection of the rotor blades

istic that prevents the distance

upward from the rotor hub.

between the rotor mast axis and

bar. This minimizes hub bar bending moments and

the center of mass of each rotor

eliminates the need for a coning hinge, which is used

blade from changing as the

in more complex rotor systems. A tower block pro-

blades teeter. This precludes

Coriolis Effect from acting on the

vides the undersling and attachment to the rotor head

speed of the rotor system.

by the teeter bolt. The rotor head is comprised of a

Undersling is further explained

in Chapter 3-Aerodynamics of

bearing block in which the bearing is mounted and

Flight, Coriolis Effect (Law of

onto which the tower plates are attached. The spindle

Conservation of Angular

(commonly, a vertically oriented bolt) attaches the

Momentum).

18-1

rotor blade pitch while in flight. This system is signifi-

MECHANICAL PREROTATOR

cantly more complicated than the teeter-head, as it

Mechanical prerotators typically have clutches or belts

requires hinges that allow each rotor blade to flap,

for engagement, a drive train, and may use a transmis-

feather, and lead or lag independently. [Figure 18-2]

sion to transfer engine power to the rotor. Friction

When used, the fully articulated rotor system of a gyro-

drives and flex cables are used in conjunction with an

plane is very similar to those used on helicopters, which

automotive type bendix and ring gear on many gyro-

is explained in depth in Chapter 5-Helicopter Systems,

planes. [Figure 18-3]

Main Rotor Systems. One major advantage of using a

fully articulated rotor in gyroplane design is that it usu-

ally allows jump takeoff capability. Rotor characteristics

required for a successful jump takeoff must include a

method of collective pitch change, a blade with sufficient

inertia, and a prerotation mechanism capable of approxi-

mately 150 percent of rotor flight r.p.m.

Figure 18-3. The mechanical prerotator used by many gyro-

planes uses a friction drive at the propeller hub, and a flexi-

Figure 18-2. The fully articulated rotor system enables the

ble cable that runs from the propeller hub to the rotor mast.

pilot to effect changes in pitch to the rotor blades, which is

When engaged, the bendix spins the ring gear located on the

necessary for jump takeoff capability.

rotor hub.

Incorporating rotor blades with high inertia potential is

desirable in helicopter design and is essential for jump

The mechanical prerotator used on jump takeoff gyro-

takeoff gyroplanes. A rotor hub design allowing the

planes may be regarded as being similar to the helicopter

rotor speed to exceed normal flight r.p.m. by over

main rotor drive train, but only operates while the air-

50 percent is not found in helicopters, and predicates a

craft is firmly on the ground. Gyroplanes do not have an

rotor head design particular to the jump takeoff

antitorque device like a helicopter, and ground contact is

gyroplane, yet very similar to that of the helicopter.

necessary to counteract the torque forces generated by

the prerotation system. If jump takeoff capability is

PREROTATOR

designed into a gyroplane, rotor r.p.m. prior to liftoff

Prior to takeoff, the gyroplane rotor must first achieve

must be such that rotor energy will support the air-

a rotor speed sufficient to create the necessary lift.

craft through the acceleration phase of takeoff. This

This is accomplished on very basic gyroplanes by ini-

combination of rotor system and prerotator utilizes

tially spinning the blades by hand. The aircraft is then

the transmission only while the aircraft is on the

taxied with the rotor disc tilted aft, allowing airflow

ground, allowing the transmission to be disconnected

through the system to accelerate it to flight r.p.m.

from both the rotor and the engine while in normal

More advanced gyroplanes use a prerotator, which

flight.

provides a mechanical means to spin the rotor. Many

prerotators are capable of only achieving a portion of

HYDRAULIC PREROTATOR

the speed necessary for flight; the remainder is

The hydraulic prerotator found on gyroplanes uses

gained by taxiing or during the takeoff roll. Because

engine power to drive a hydraulic pump, which in turn

of the wide variety of prerotation systems available,

drives a hydraulic motor attached to an automotive type

you need to become thoroughly familiar with the

bendix and ring gear. [Figure 18-4] This system also

characteristics and techniques associated with your

requires that some type of clutch and pressure regula-

particular system.

tion be incorporated into the design.

18-2

Figure 18-4. This prerotator uses belts at the propeller hub to drive a hydraulic pump, which drives a hydraulic motor on the

rotor mast.

ELECTRIC PREROTATOR

TIP JETS

The electric prerotator found on gyroplanes uses an

Jets located at the rotor blade tips have been used in sev-

automotive type starter with a bendix and ring gear

eral applications for prerotation, as well as for hover

mounted at the rotor head to impart torque to the rotor

flight. This system has no requirement for a transmission

system. [Figure 18-5] This system has the advantage of

or clutches. It also has the advantage of not imparting

simplicity and ease of operation, but is dependent on

torque to the airframe, allowing the rotor to be powered

having electrical power available. Using a “soft start”

in flight to give increased climb rates and even the ability

device can alleviate the problems associated with the

to hover. The major disadvantage is the noise generated

high starting torque initially required to get the rotor

by the jets. Fortunately, tip jets may be shut down while

system turning. This device delivers electrical pulses to

operating in the autorotative gyroplane mode.

the starter for approximately 10 seconds before con-

necting uninterrupted voltage.

INSTRUMENTATION

The instrumentation required for flight is generally

related to the complexity of the gyroplane. Some gyro-

planes using air-cooled and fuel/oil-lubricated engines

may have limited instrumentation.

ENGINE INSTRUMENTS

All but the most basic engines require monitoring

instrumentation for safe operation. Coolant tempera-

ture, cylinder head temperatures, oil temperature, oil

pressure, carburetor air temperature, and exhaust gas

temperature are all direct indications of engine opera-

tion and may be displayed. Engine power is normally

indicated by engine r.p.m., or by manifold pressure on

gyroplanes with a constant speed propeller.

ROTOR TACHOMETER

Most gyroplanes are equipped with a rotor r.p.m. indica-

tor. Because the pilot does not normally have direct

control of rotor r.p.m. in flight, this instrument is most

useful on the takeoff roll to determine when there is suf-

ficient rotor speed for liftoff. On gyroplanes not

Figure 18-5. The electric prerotator is simple and easy to use,

equipped with a rotor tachometer, additional piloting

but requires the availability of electrical power.

skills are required to sense rotor r.p.m. prior to takeoff.

18-3

Certain gyroplane maneuvers require you to know pre-

speed indicator is used, as in some very basic

cisely the speed of the rotor system. Performing a jump

amateur-built machines, you must have a very acute

takeoff in a gyroplane with collective control is one

sense of “q” (impact air pressure against your body).

example, as sufficient rotor energy must be available

for the successful outcome of the maneuver. When

ALTIMETER

variable collective and a rotor tachometer are used,

For the average pilot, it becomes increasingly difficult

more efficient rotor operation may be accomplished by

to judge altitude accurately when more than several

using the lowest practical rotor r.p.m. [Figure 18-6]

hundred feet above the ground. A conventional altime-

ter may be used to provide an altitude reference when

flying at higher altitudes where human perception

degrades.

IFR FLIGHT INSTRUMENTATION

Gyroplane flight into instrument meteorological condi-

tions requires adequate flight instrumentation and navi-

gational systems, just as in any aircraft. Very few

gyroplanes have been equipped for this type of operation.

The majority of gyroplanes do not meet the stability

requirements for single-pilot IFR flight. As larger and

more advanced gyroplanes are developed, issues of IFR

flight in these aircraft will have to be addressed.

Figure 18-6. A rotor tachometer can be very useful to deter-

mine when rotor r.p.m. is sufficient for takeoff.

GROUND HANDLING

The gyroplane is capable of ground taxiing in a manner

similar to that of an airplane. A steerable nose wheel,

SLIP/SKID INDICATOR

which may be combined with independent main wheel

A yaw string attached to the nose of the aircraft and a

brakes, provides the most common method of control.

conventional inclinometer are often used in gyroplanes

[Figure 18-8] The use of independent main wheel

to assist in maintaining coordinated flight. [Figure 18-7]

brakes allows differential braking, or applying more

braking to one wheel than the other to achieve tight

radius turns. On some gyroplanes, the steerable nose

wheel is equipped with a foot-operated brake rather

than using main wheel brakes. One limitation of this

system is that the nose wheel normally supports only a

fraction of the weight of the gyroplane, which greatly

reduces braking effectiveness. Another drawback is the

Figure 18-7. A string simply tied near the nose of the gyro-

plane that can be viewed from the cockpit is often used to

indicate rotation about the yaw axis. An inclinometer may

also be used.

AIRSPEED INDICATOR

Airspeed knowledge is essential and is most easily

obtained by an airspeed indicator that is designed for

Figure 18-8. Depending on design, main wheel brakes can be

accuracy at low airspeeds. Wind speed indicators

operated either independently or collectively. They are con-

have been adapted to many gyroplanes. When no air-

siderably more effective than nose wheel brakes.

18-4

As with most certificated aircraft manufactured after

This format is the same as that used by helicopters,

March 1979, FAA-certificated gyroplanes are required

which is explained in depth in Chapter 6-Rotorcraft

to have an approved flight manual. The flight manual

Flight Manual (Helicopter).

describes procedures and limitations that must be

adhered to when operating the aircraft. Specification

Amateur-built gyroplanes may have operating limita-

for Pilot’s Operating Handbook, published by the

tions but are not normally required to have an approved

General Aviation Manufacturers Association (GAMA),

flight manual. One exception is an exemption granted

provides a recommended format that more recent gyro-

by the FAA that allows the commercial use of

plane flight manuals follow. [Figure 19-1]

two-place, amateur-built gyroplanes for instructional

purposes. One of the conditions of this exemption is to

have an approved flight manual for the aircraft. This

ROTORCRAFT FLIGHT MANUAL

manual is to be used for training purposes, and must be

GENERAL-Presents basic information, such as loading,

carried in the gyroplane at all times.

handling, and preflight of the gyroplane. Also includes

definitions, abbreviations, symbology, and terminology

explanations.

USING THE FLIGHT MANUAL

LIMITATIONS-Includes operating limitations, instrument

markings, color coding, and basic placards necessary for the

The flight manual is required to be on board the aircraft

safe operation of the gyroplane.

to guarantee that the information contained therein is

EMERGENCY PROCEDURES-Provides checklists followed

readily available. For the information to be of value,

by amplified procedures for coping with various types of

you must be thoroughly familiar with the manual and

emergencies or critical situations. Related recommended

be able to read and properly interpret the various charts

airspeeds are also included. At the manufacturer's option, a

section of abnormal procedures may be included to describe

and tables.

recommendations for handling equipment malfunctions or other

abnormalities that are not of an emergency nature.

NORMAL PROCEDURES-Includes checklists followed by

WEIGHT AND BALANCE SECTION

amplified procedures for conducting normal operations.

The weight and balance section of the flight manual

Related recommended airspeeds are also provided.

contains information essential to the safe operation of

PERFORMANCE-Gives

performance

information

the gyroplane. Careful consideration must be given to

appropriate to the gyroplane, plus optional information

the weight of the passengers, baggage, and fuel prior to

presented in the most likely order for use in flight.

each flight. In conducting weight and balance compu-

WEIGHT AND BALANCE-Includes weighing procedures,

weight and balance records, computation instructions, and

tations, many of the terms and procedures are similar to

the equipment list.

those used in helicopters. These are further explained

AIRCRAFT AND SYSTEMS DESCRIPTION-Describes the

in Chapter 7-Weight and Balance. In any aircraft,

gyroplane and its systems in a format considered by the

failure to adhere to the weight and balance limita-

manufacturer to be most informative.

tions prescribed by the manufacturer can be

HANDLING, SERVICE, AND MAINTENANCE-Includes

extremely hazardous.

information on gyroplane inspection periods, preventative

maintenance that can be performed by the pilot, ground

handling procedures, servicing, cleaning, and care instructions.

SAMPLE PROBLEM

SUPPLEMENTS-Contains information necessary to safely

As an example of a weight and balance computation,

and efficiently operate the gyroplane's various optional

systems and equipment.

assume a sightseeing flight in a two-seat, tandem-con-

figured gyroplane with two people aboard. The pilot,

SAFETY AND OPERATIONAL TIPS-Includes optional

seated in the front, weighs 175 pounds while the rear

information from the manufacturer of a general nature

addressing safety practices and procedures.

seat passenger weighs 160 pounds. For the purposes of

this example, there will be no baggage carried. The

Figure 19-1. The FAA-approved flight manual may contain as

basic empty weight of the aircraft is 1,315 pounds with

many as ten sections, as well as an optional alphabetical

index.

a moment, divided by 1,000, of 153.9 pound-inches.

19-1

Using the loading graph [Figure

19-2], the

Moment

Weight

moment/1000 of the pilot is found to be 9.1 pound-

(lb.-ins.

(lbs.)

inches, and the passenger has a moment/1000 of 13.4

/1,000)

pound-inches.

1. Total Aircraft Weight

(Less Fuel)

1,650

176.4

3. Fuel

108

11.9

LOADING GRAPH

TOTALS

1,758

188.3

CENTER OF GRAVITY ENVELOPE

Load Moment in Thousands of LBS - IN

A = Pilot

C = Fuel

B = Passenger

D = Baggage

Figure 19-2. A loading graph is used to determine the load

moment for weights at various stations.

160

170

180

190

200

Gross Moment in Thousands of LBS-IN.

Figure 19-4. Center of gravity envelope chart.

Adding these figures, the total weight of the aircraft for

this flight (without fuel) is determined to be 1,650

pounds with a moment/1000 of 176.4 pound-inches.

[Figure 19-3]

PERFORMANCE SECTION

The performance section of the flight manual contains

data derived from actual flight testing of the aircraft.

Weight

Moment

Because the actual performance may differ, it is pru-

(pounds)

(lb.-in./1,000)

dent to maintain a margin of safety when planning

Basic Empty Weight

1,315

153.9

operations using this data.

Pilot

175

9.1

Passenger

160

13.4

SAMPLE PROBLEM

Baggage

For this example, a gyroplane at its maximum gross

Total Aircraft (Less Fuel)

1,650

176.4

weight (1,800 lbs.) needs to perform a short field take-

Max Gross Weight = 1,800 lbs.

off due to obstructions in the takeoff path. Present

weather conditions are standard temperature at a pres-

Figure 19-3. Loading of the sample aircraft, less fuel.

sure altitude of 2,000 feet, and the wind is calm.

Referring to the appropriate performance chart [Figure

19-5], the takeoff distance to clear a 50-foot obstacle is

The maximum gross weight for the sample aircraft is

determined by entering the chart from the left at the

1,800 pounds, which allows up to 150 pounds to be car-

pressure altitude of 2,000 feet. You then proceed hori-

ried in fuel. For this flight, 18 gallons of fuel is deemed

zontally to the right until intersecting the appropriate

sufficient. Allowing six pounds per gallon of fuel, the

temperature reference line, which in this case is the

fuel weight on the aircraft totals 108 pounds. Referring

dashed standard temperature line. From this point,

again to the loading graph [Figure 19-2], 108 pounds of

descend vertically to find the total takeoff distance to

fuel would have a moment/1000 of 11.9 pound-inches.

clear a 50-foot obstacle. For the conditions given, this

This is added to the previous totals to obtain the total

particular gyroplane would require a distance of 940

aircraft weight of 1,758 pounds and a moment/1000 of

feet for ground roll and the distance needed to climb 50

188.3. Locating this point on the center of gravity enve-

feet above the surface. Notice that the data presented in

lope chart [Figure 19-4], shows that the loading is

this chart is predicated on certain conditions, such as a

within the prescribed weight and balance limits.

running takeoff to 30 m.p.h., a 50 m.p.h. climb speed, a

19-2

TOTAL TAKEOFF DISTANCE

TO CLEAR 50 FT. OBSTACLE

Running Takeoff to 30 MPH & Climb out at 50 MPH CAS

Weight 1800 LBS

Rotor Prerotated to 370 RPM

Zero Wind

0° F

20° F

Std. Temp.

40° F

60° F

80° F

100° F

Total Takeoff Distance to Clear 50 FT Obstacle in Feet (x 100)

Figure 19-5. Takeoff performance chart.

rotor prerotation speed of 370 r.p.m., and no wind.

which provide important information that may not be

Variations from these conditions alter performance,

committed to memory.

possibly to the point of jeopardizing the successful out-

come of the maneuver.

HEIGHT/VELOCITY DIAGRAM

HEIGHT vs. VELOCITY

FOR SAFE LANDING

Like helicopters, gyroplanes have a height/velocity

diagram that defines what speed and altitude combina-

Avoid Continuous Operation In

tions allow for a safe landing in the event of an engine

Shaded Area.

failure. [Figure 19-6]

400

During an engine-out landing, the cyclic flare is used to

300

arrest the vertical velocity of the aircraft and most of the

forward velocity. On gyroplanes with a manual collec-

tive control, increasing blade pitch just prior to touch-

200

down can further reduce ground roll. Typically, a

gyroplane has a lower rotor disc loading than a helicop-

ter, which provides a slower rate of descent in autorota-

100

tion. The power required to turn the main transmission,

tail rotor transmission, and tail rotor also add to the

higher descent rate of a helicopter in autorotation as

compared with that of a gyroplane.

100

Indicated Airspeed In MPH

EMERGENCY SECTION

Because in-flight emergencies may not allow enough

time to reference the flight manual, the emergency sec-

tion should be reviewed periodically to maintain

Figure

19-6. Operations within the shaded area of a

familiarity with these procedures. Many aircraft also

height/velocity diagram may not allow for a safe landing and

use placards and instrument markings in the cockpit,

are to be avoided.

19-3

The diversity of gyroplane designs available today

potential. The placement and accessibility of charts,

yields a wide variety of capability and performance.

writing materials, and other necessary items must be

For safe operation, you must be thoroughly familiar

carefully considered. Gyroplanes with open cockpits

with the procedures and limitations for your particular

add the challenge of coping with wind, which further

aircraft along with other factors that may affect the

increases the need for creative and resourceful cockpit

safety of your flight.

management for optimum efficiency.

PREFLIGHT

ENGINE STARTING

As pilot in command, you are the final authority in

The dissimilarity between the various types of engines

determining the airworthiness of your aircraft.

used for gyroplane propulsion necessitates the use of

Adherence to a preflight checklist greatly enhances

an engine start checklist. Again, when a checklist is not

your ability to evaluate the fitness of your gyroplane by

provided, it is advisable to create one for the safety of

ensuring that a complete and methodical inspection of

yourself and others, and to prevent inadvertent damage

all components is performed. [Figure 20-1] For aircraft

to the engine or propeller. Being inherently dangerous,

without a formal checklist, it is prudent to create one

the propeller demands special attention during engine

that is specific to the aircraft to be sure that important

starting procedures. Always ensure that the propeller

items are not overlooked. To determine the status of

area is clear prior to starting. In addition to providing

required inspections, a preflight review of the aircraft

an added degree of safety, being thoroughly familiar

records is also necessary.

with engine starting procedures and characteristics can

also be very helpful in starting an engine under various

weather conditions.

TAXIING

The ability of the gyroplane to be taxied greatly

enhances its utility. However, a gyroplane should not

be taxied in close proximity to people or obstructions

while the rotor is turning. In addition, taxi speed should

be limited to no faster than a brisk walk in ideal condi-

tions, and adjusted appropriately according to the

circumstances.

BLADE FLAP

On a gyroplane with a semi-rigid, teeter-head rotor sys-

tem, blade flap may develop if too much airflow passes

through the rotor system while it is operating at low

r.p.m. This is most often the result of taxiing too fast

Figure 20-1. A checklist is extremely useful in conducting a

thorough preflight inspection.

for a given rotor speed. Unequal lift acting on the

advancing and retreating blades can cause the blades to

teeter to the maximum allowed by the rotor head

design. The blades then hit the teeter stops, creating a

COCKPIT MANAGEMENT

vibration that may be felt in the cyclic control. The fre-

As in larger aircraft, cockpit management is an impor-

quency of the vibration corresponds to the speed of the

tant skill necessary for the safe operation of a

rotor, with the blades hitting the stops twice during

gyroplane. Intrinsic to these typically small aircraft is a

each revolution. If the flapping is not controlled, the

limited amount of space that must be utilized to its

situation can grow worse as the blades begin to flex and

20-1

bend. Because the system is operating at low r.p.m.,

BEFORE TAKEOFF

there is not enough centrifugal force acting on the

For the amateur-built gyroplane using single ignition

blades to keep them rigid. The shock of hitting the

and a fixed trim system, the before takeoff check is

teeter stops combined with uneven lift along the length

quite simple. The engine should be at normal operating

of the blade causes an undulation to begin, which can

temperature, and the area must be clear for prerotation.

increase in severity if allowed to progress. In extreme

Certificated gyroplanes using conventional aircraft

cases, a rotor blade may strike the ground or propeller.

engines have a checklist that includes items specific to

[Figure 20-2]

the powerplant. These normally include, but are not

limited to, checks for magneto drop, carburetor heat,

and, if a constant speed propeller is installed, that it be

cycled for proper operation.

Following the engine run-up is the procedure for

accomplishing prerotation. This should be reviewed

and committed to memory, as it typically requires both

hands to perform.

PREROTATION

Prerotation of the rotor can take many forms in a

gyroplane. The most basic method is to turn the rotor

blades by hand. On a typical gyroplane with a counter-

clockwise rotating rotor, prerotation by hand is done on

the right side of the rotor disk. This allows body

Figure 20-2. Taxiing too fast or gusting winds can cause

movement to be directed away from the propeller to

blade flap in a slow turning rotor. If not controlled, a rotor

minimize the risk of injury. Other methods of prerota-

blade may strike the ground.

tion include using mechanical, electrical, or hydraulic

means for the initial blade spin-up. Many of these

systems can achieve only a portion of the rotor speed

To avoid the onset of blade flap, always taxi the gyro-

that is necessary for takeoff. After the prerotator is

plane at slow speeds when the rotor system is at low

disengaged, taxi the gyroplane with the rotor disk tilted

r.p.m. Consideration must also be given to wind speed

aft to allow airflow through the rotor. This increases

and direction. If taxiing into a 10-knot headwind, for

rotor speed to flight r.p.m. In windy conditions, facing

example, the airflow through the rotor will be 10 knots

the gyroplane into the wind during prerotation assists

faster than the forward speed of the gyroplane, so the

in achieving the highest possible rotor speed from the

taxi speed should be adjusted accordingly. When pre-

prerotator. A factor often overlooked that can nega-

rotating the rotor by taxiing with the rotor disc tilted

tively affect the prerotation speed is the cleanliness of

aft, allow the rotor to accelerate slowly and smoothly.

the rotor blades. For maximum efficiency, it is recom-

In the event blade flap is encountered, apply forward

mended that the rotor blades be cleaned periodically.

cyclic to reduce the rotor disc angle and slow the gyro-

By obtaining the maximum possible rotor speed

plane by reducing throttle and applying the brakes, if

through the use of proper prerotation techniques, you

needed. [Figure 20-3]

Rotor

Ground

Clearance

Airflow

Figure 20-3. Decreasing the rotor disc angle of attack with forward cyclic can reduce the excessive amount of airflow causing

the blade flap. This also allows greater clearance between the rotor blades and the surface behind the gyroplane, minimizing

the chances of a blade striking the ground.

20-2

minimize the length of the ground roll that is required

NORMAL TAKEOFF

to get the gyroplane airborne.

The normal takeoff assumes that a prepared surface of

adequate length is available and that there are no high

The prerotators on certificated gyroplanes remove the

obstructions to be cleared within the takeoff path. The

possibility of blade flap during prerotation. Before the

normal takeoff for most amateur-built gyroplanes is

clutch can be engaged, the pitch must be removed from

accomplished by prerotating to sufficient rotor r.p.m. to

the blades. The rotor is then prerotated with a 0° angle

prevent blade flapping and tilting the rotor back with

of attack on the blades, which prevents lift from being

cyclic control. Using a speed of 20 to 30 m.p.h., allow

produced and precludes the possibility of flapping.

the rotor to accelerate and begin producing lift. As lift

When the desired rotor speed is achieved, blade pitch is

increases, move the cyclic forward to decrease the pitch

increased for takeoff.

angle on the rotor disc. When appreciable lift is being

produced, the nose of the aircraft rises, and you can feel

an increase in drag. Using coordinated throttle and

TAKEOFF

flight control inputs, balance the gyroplane on the main

Takeoffs are classified according to the takeoff surface,

gear without the nose wheel or tail wheel in contact

obstructions, and atmospheric conditions. Each type of

with the surface. At this point, smoothly increase power

takeoff assumes that certain conditions exist. When

to full thrust and hold the nose at takeoff attitude with

conditions dictate, a combination of takeoff techniques

cyclic pressure. The gyroplane will lift off at or near

can be used. Two important speeds used for takeoff and

the minimum power required speed for the aircraft. V_X

initial climbout are V_X and V_Y. V_X is defined as the

should be used for the initial climb, then V_Y for the

speed that provides the best angle of climb, and will

remainder of the climb phase.

yield the maximum altitude gain over a given distance.

This speed is normally used when obstacles on the

A normal takeoff for certificated gyroplanes is accom-

ground are a factor. Maintaining V_Y speed ensures the

plished by prerotating to a rotor r.p.m. slightly above

aircraft will climb at its maximum rate, providing the

that required for flight and disengaging the rotor drive.

most altitude gain for a given period of time.

The brakes are then released and full power is applied.

[Figure 20-4] Prior to any takeoff or maneuver, you

Lift off will not occur until the blade pitch is increased

should ensure that the area is clear of other traffic.

to the normal in-flight setting and the rotor disk tilted

Figure 20-4. Best angle-of-climb (V_X) speed is used when obstacles are a factor. V_Y provides the most altitude gain for a given

amount of time.

20-3

aft. This is normally accomplished at approximately 30

power applied as soon as appreciable lift is felt. V_X

to 40 m.p.h. The gyroplane should then be allowed to

climb speed should be maintained until the obstruction

accelerate to V_X for the initial climb, followed by V_Y

is cleared. Familiarity with the rotor acceleration

for the remainder of the climb. On any takeoff in a

characteristics and proper technique are essential for

gyroplane, engine torque causes the aircraft to roll

optimum short-field performance.

opposite the direction of propeller rotation, and

adequate compensation must be made.

If the prerotator is capable of spinning the rotor in

excess of normal flight r.p.m., the stored energy may be

CROSSWIND TAKEOFF

used to enhance short-field performance. Once maxi-

A crosswind takeoff is much like a normal takeoff,

mum rotor r.p.m. is attained, disengage the rotor drive,

except that you have to use the flight controls to

release the brakes, and apply power. As airspeed and

compensate for the crosswind component. The term

rotor r.p.m. increase, apply additional power until full

crosswind component refers to that part of the wind

power is achieved. While remaining on the ground,

which acts at right angles to the takeoff path. Before

accelerate the gyroplane to a speed just prior to V_X. At

attempting any crosswind takeoff, refer to the flight

that point, tilt the disk aft and increase the blade pitch

manual, if available, or the manufacturer’s recommen-

to the normal in-flight setting. The climb should be at a

dations for any limitations.

speed just under V_X until rotor r.p.m. has dropped to

normal flight r.p.m. or the obstruction has been cleared.

Begin the maneuver by aligning the gyroplane into the

When the obstruction is no longer a factor, increase the

wind as much as possible. At airports with wide

airspeed to V_Y.

runways, you might be able to angle your takeoff roll

down the runway to take advantage of as much head-

COMMON ERRORS

wind as you can. As airspeed increases, gradually tilt

Failure to position gyroplane for maximum

the rotor into the wind and use rudder pressure to

utilization of available takeoff area.

maintain runway heading. In most cases, you should

Failure to check rotor for proper operation, track,

accelerate to a speed slightly faster than normal liftoff

and r.p.m. prior to takeoff.

speed. As you reach takeoff speed, the downwind wheel

lifts off the ground first, followed by the upwind wheel.

Improper initial positioning of flight controls.

Once airborne, remove the cross-control inputs and

Improper application of power.

establish a crab, if runway heading is to be maintained.

Improper use of brakes.

Due to the maneuverability of the gyroplane, an immedi-

ate turn into the wind after lift off can be safely executed,

Poor directional control.

if this does not cause a conflict with existing traffic.

Failure to lift off at proper airspeed.

COMMON ERRORS FOR NORMAL AND

Failure to establish and maintain proper climb

CROSSWIND TAKEOFFS

attitude and airspeed.

Failure to check rotor for proper operation, track,

Drifting from the desired ground track during the

and r.p.m. prior to takeoff.

climb.

Improper initial positioning of flight controls.

HIGH-ALTITUDE TAKEOFF

Improper application of power.

A high-altitude takeoff is conducted in a manner very

similar to that of the short-field takeoff, which achieves

Poor directional control.

maximum performance from the aircraft during each

Failure to lift off at proper airspeed.

phase of the maneuver. One important consideration is

Failure to establish and maintain proper climb

that at higher altitudes, rotor r.p.m. is higher for a given

attitude and airspeed.

blade pitch angle. This higher speed is a result of thin-

ner air, and is necessary to produce the same amount of

Drifting from the desired ground track during the

lift. The inertia of the excess rotor speed should not be

climb.

used in an attempt to enhance climb performance.

SHORT-FIELD TAKEOFF

Another important consideration is the effect of alti-

Short-field takeoff and climb procedures may be

tude on engine performance. As altitude increases, the

required when the usable takeoff surface is short, or

amount of oxygen available for combustion decreases.

when it is restricted by obstructions, such as trees,

In normally aspirated engines, it may be necessary to

powerlines, or buildings, at the departure end. The

technique is identical to the normal takeoff, with

performance being optimized during each phase. Using

the help from wind and propwash, the maximum rotor

Normally Aspirated-An engine that does not compensate for decreases

in atmospheric pressure through turbocharging or other means.

r.p.m. should be attained from the prerotator and full

20-4

adjust the fuel/air mixture to achieve the best possible

power output. This process is referred to as “leaning

the mixture.” If you are considering a high-altitude

takeoff, and it appears that the climb performance limit

of the gyroplane is being approached, do not attempt a

takeoff until more favorable conditions exist.

SOFT-FIELD TAKEOFF

A soft field may be defined as any takeoff surface that

measurably retards acceleration during the takeoff roll.

The objective of the soft-field takeoff is to transfer the

weight of the aircraft from the landing gear to the rotor

as quickly and smoothly as possible to eliminate the

drag caused by surfaces, such as tall grass, soft dirt, or

snow. This takeoff requires liftoff at a speed just above

the minimum level flight speed for the aircraft. Due to

design, many of the smaller gyroplanes have a limited

Figure 20-5. During a jump takeoff, excess rotor inertia is

used to lift the gyroplane nearly vertical, where it is then

pitch attitude available, as tail contact with the ground

accelerated through minimum level flight speed.

prevents high pitch attitudes until in flight. At mini-

mum level flight speed, the pitch attitude is often such

that the tail wheel is lower than the main wheels. When

performing a soft-field takeoff, these aircraft require

minimum level flight speed. Failure to have sufficient

slightly higher liftoff airspeeds to allow for proper tail

rotor r.p.m. for a jump takeoff results in the gyroplane

clearance.

settling back to the ground. Before attempting a jump

takeoff, it is essential that you first determine if it is

COMMON ERRORS

possible given the existing conditions by consulting the

Failure to check rotor for proper operation, track,

relevant performance chart. Should conditions of

and r.p.m. prior to takeoff.

weight, altitude, temperature, or wind leave the suc-

cessful outcome of the maneuver in doubt, it should not

Improper initial positioning of flight controls.

be attempted.

Improper application of power.

The prudent pilot may also use a “rule of thumb” for

Allowing gyroplane to lose momentum by

predicting performance before attempting a jump take-

slowing or stopping on takeoff surface prior to

off. As an example, suppose that a particular gyroplane

initiating takeoff.

is known to be able to make a jump takeoff and remain

Poor directional control.

airborne to accelerate to V_X at a weight of 1,800 pounds

and a density altitude of 2,000 feet. Since few takeoffs

Improper pitch attitude during lift-off.

are made under these exact conditions, compensation

Settling back to takeoff surface after becoming

must be made for variations in weight, wind, and den-

airborne.

sity altitude. The “rule of thumb” being used for this

particular aircraft stipulates that 1,000 feet of density

Failure to establish and maintain proper climb

altitude equates with 10 m.p.h. wind or 100 pounds of

attitude and airspeed.

gross weight. To use this equation, you must first deter-

Drifting from the desired ground track during the

mine the density altitude. This is accomplished by

climb.

setting your altimeter to the standard sea level pressure

setting of 29.92 inches of mercury and reading the pres-

JUMP TAKEOFF

sure altitude. Next, you must correct for nonstandard

Gyroplanes with collective pitch change, and the

temperature. Standard temperature at sea level is 59°F

ability to prerotate the rotor system to speeds approxi-

(15°C) and decreases 3.5°F (2°C) for every additional

mately 50 percent higher than those required for

normal flight, are capable of achieving extremely short

takeoff rolls. Actual jump takeoffs can be performed

under the proper conditions. A jump takeoff requires no

ground roll, making it the most effective soft-field and

crosswind takeoff procedure. [Figure 20-5] A jump

takeoff is possible because the energy stored in the

Density Altitude-Pressure altitude corrected for nonstandard temper-

blades, as a result of the higher rotor r.p.m., is used to

ature. This is a theoretical value that is used in determining aircraft

performance.

keep the gyroplane airborne as it accelerates through

20-5

one thousand feet of pressure altitude. [Figure 20-6]

variety in designs, many gyroplanes have only basic

Once you have determined the standard temperature

instruments available, and the pilot is often exposed to

for your pressure altitude, compare it with the actual

the airflow. In addition, the visual clues found on other

existing conditions. For every 10°F (5.5°C) the actual

aircraft, such as cowlings, wings, and windshields

temperature is above standard, add 750 feet to the

might not be part of your gyroplane’s design.

pressure altitude to estimate the density altitude. If the

Therefore, much more reliance is placed on pilot

density altitude is above 2,000 feet, a jump takeoff in

interpretation of flight attitude and the “feel” of the

this aircraft should not be attempted unless wind and/or

gyroplane than in other types of aircraft. Acquiring the

a weight reduction would compensate for the decrease

skills to precisely control a gyroplane can be a

in performance. Using the equation, if the density alti-

challenging and rewarding experience, but requires

tude is 3,000 feet (1,000 feet above a satisfactory jump

dedication and the direction of a competent instructor.

density altitude), a reduction of 100 pounds in gross

weight or a 10 m.p.h. of wind would still allow a satis-

STRAIGHT-AND-LEVEL FLIGHT

factory jump takeoff. Additionally, a reduction of 50

Straight-and-level flight is conducted by maintaining a

pounds in weight combined with a 5 m.p.h. wind would

constant altitude and a constant heading. In flight, a

also allow a satisfactory jump. If it is determined that a

gyroplane essentially acts as a plumb suspended from

jump takeoff should not be conducted because the

the rotor. As such, torque forces from the engine cause

weight cannot be reduced or an appropriate wind is not

the airframe to be deflected a few degrees out of the

blowing, then consideration should be given to a

vertical plane. This very slight “out of vertical”

rolling takeoff. A takeoff roll of 10 m.p.h. is equivalent

condition should be ignored and the aircraft flown to

to a wind speed of 10 m.p.h. or a reduction of 100

maintain a constant heading.

pounds in gross weight. It is important to note that a

jump takeoff is predicated on having achieved a spe-

The throttle is used to control airspeed. In level flight,

cific rotor r.p.m. If this r.p.m. has not been attained,

when the airspeed of a gyroplane increases, the rotor

performance is unpredictable, and the maneuver should

disc angle of attack must be decreased. This causes

not be attempted.

pitch control to become increasingly more sensitive.

[Figure 20-7] As this disc angle becomes very small, it

is possible to overcontrol a gyroplane when encounter-

20,000

ing turbulence. For this reason, when extreme

19,000

turbulence is encountered or expected, airspeed should

18,000

17,000

be decreased. Even in normal conditions, a gyroplane

16,000

requires constant attention to maintain straight-and-

15,000

level flight. Although more stable than helicopters,

14,000

gyroplanes are less stable than airplanes. When cyclic

13,000

trim is available, it should be used to relieve any stick

12,000

forces required during stabilized flight.

11,000

10,000

9,000

8,000

7,000

6,000

5,000

Rotor

4.000

Disk

3,000

Angle

Low Speed

2,000

1,000

Sea Level

-25

-20

-15

-10

-5

°C

–12

°F

High Speed

Figure 20-7. The angle of the rotor disc decreases at higher

cruise speeds, which increases pitch control sensitivity.

Figure 20-6. Standard temperature chart.

CLIMBS

A climb is achieved by adding power in excess of what

BASIC FLIGHT MANEUVERS

is required for straight-and-level flight at a particular

Conducting flight maneuvers in a gyroplane is differ-

airspeed. The amount of excess power used is directly

ent than in most other aircraft. Because of the wide

proportional to the climb rate. For maneuvers when

20-6

maximum performance is desired, two important climb

The bank angle used for a turn directly affects the rate

speeds are best angle-of-climb speed and best rate-of-

of turn. As the bank is steepened, the turn rate

climb speed.

increases, but more power is required to maintain alti-

tude. A bank angle can be reached where all available

Because a gyroplane cannot be stalled, it may be tempt-

power is required, with any further increase in bank

ing to increase the climb rate by decreasing airspeed.

resulting in a loss of airspeed or altitude. Turns during a

This practice, however, is self-defeating. Operating

climb should be made at the minimum angle of bank

below the best angle-of-climb speed causes a diminish-

necessary, as higher bank angles would require more

ing rate of climb. In fact, if a gyroplane is slowed to the

power that would otherwise be available for the climb.

minimum level flight speed, it requires full power just

Turns while gliding increase the rate of descent and may

to maintain altitude. Operating in this performance

be used as an effective way of losing excess altitude.

realm, sometimes referred to as the “backside of the

power curve,” is desirable in some maneuvers, but can

SLIPS

be hazardous when maximum climb performance is

A slip occurs when the gyroplane slides sideways

required. For further explanation of a gyroplane power

toward the center of the turn. [Figure 20-8] It is caused

curve, see Flight at Slow Airspeeds, which is discussed

by an insufficient amount of rudder pedal in the direc-

later in this chapter.

tion of the turn, or too much in the direction opposite

the turn. In other words, holding improper rudder pedal

DESCENTS

pressure keeps the nose from following the turn, the

A descent is the result of using less power than that

gyroplane slips sideways toward the center of the turn.

required for straight-and-level flight at a particular

airspeed. Varying engine power during a descent allows

Slip

you to choose a variety of descent profiles. In a power-off

descent, the minimum descent rate is achieved by using

the airspeed that would normally be used for level flight

at minimum power, which is also very close to the speed

used for the best angle of climb. When distance is a factor

during a power-off descent, maximum gliding distance

HCL

Inertia

can be achieved by maintaining a speed very close to the

best rate-of-climb airspeed. Because a gyroplane can be

safely flown down to zero airspeed, a common error in

this type of descent is attempting to extend the glide by

Figure 20-8. During a slip, the rate of turn is too slow for the

raising the pitch attitude. The result is a higher rate of

angle of bank used, and the horizontal component of lift

descent and less distance being covered. For this reason,

(HCL) exceeds inertia. You can reestablish equilibrium by

decreasing the angle of bank, increasing the rate of turn by

proper glide speed should be adhered to closely. Should a

applying rudder pedal, or a combination of the two.

strong headwind exist, while attempting to achieve the

maximum distance during a glide, a rule of thumb to

achieve the greatest distance is to increase the glide speed

SKIDS

by approximately 25 percent of the headwind. The atti-

A skid occurs when the gyroplane slides sideways away

tude of the gyroplane for best glide performance is

from the center of the turn. [Figure 20-9] It is caused by

learned with experience, and slight pitch adjustments are

too much rudder pedal pressure in the direction of the

made for the proper airspeed. If a descent is needed to

turn, or by too little in the direction opposite the turn. If

lose excess altitude, slowing the gyroplane to below the

the gyroplane is forced to turn faster with increased

best glide speed increases the rate of descent. Typically,

pedal pressure instead of by increasing the degree of

slowing to zero airspeed results in a descent rate twice

that of maintaining the best glide speed.

Skid

TURNS

Turns are made in a gyroplane by banking the rotor disc

with cyclic control. Once the area, in the direction of the

turn, has been cleared for traffic, apply sideward pres-

HCL

Inertia

sure on the cyclic until the desired bank angle is

achieved. The speed at which the gyroplane enters the

bank is dependent on how far the cyclic is displaced.

When the desired bank angle is reached, return the

Figure 20-9. During a skid, inertia exceeds the HCL. To

cyclic to the neutral position. The rudder pedals are used

reestablish equilibrium, increase the bank angle or reduce

to keep the gyroplane in longitudinal trim throughout

the rate of turn by applying rudder pedal. You may also use a

the turn, but not to assist in establishing the turn.

combination of these two corrections.

20-7

bank, it skids sideways away from the center of the turn

aircraft in the vicinity. Prior to each maneuver, a clear-

instead of flying in its normal curved pattern.

ing turn should be accomplished to ensure the practice

area is free of conflicting traffic.

COMMON ERRORS DURING BASIC FLIGHT

MANEUVERS

RECTANGULAR COURSE

The rectangular course is a training maneuver in which

Improper coordination of flight controls.

the ground track of the gyroplane is equidistant from

Failure to cross-check and correctly interpret

all sides of a selected rectangular area on the ground.

outside and instrument references.

[Figure 20-10] While performing the maneuver, the

altitude and airspeed should be held constant. The rec-

Using faulty trim technique.

tangular course helps you to develop a recognition of a

drift toward or away from a line parallel to the intended

STEEP TURNS

ground track. This is helpful in recognizing drift toward

A steep turn is a performance maneuver used in

or from an airport runway during the various legs of the

training that consists of a turn in either direction at a

airport traffic pattern.

bank angle of approximately 40°. The objective of

performing steep turns is to develop smoothness, coor-

For this maneuver, pick a square or rectangular field, or

dination, orientation, division of attention, and control

an area bounded on four sides by section lines or roads,

techniques.

where the sides are approximately a mile in length. The

Prior to initiating a steep turn, or any other flight

area selected should be well away from other air traf-

maneuver, first complete a clearing turn to check the

fic. Fly the maneuver approximately 600 to 1,000 feet

area for traffic. To accomplish this, you may execute

above the ground, which is the altitude usually required

either one 180° turn or two 90° turns in opposite

for an airport traffic pattern. You should fly the

directions. Once the area has been cleared, roll the

gyroplane parallel to and at a uniform distance, about

gyroplane into a

40° angle-of-bank turn while

one-fourth to one-half mile, from the field boundaries,

smoothly adding power and slowly moving the cyclic

not above the boundaries. For best results, position

aft to maintain altitude. Maintain coordinated flight

your flight path outside the field boundaries just far

with proper rudder pedal pressure. Throughout the turn,

enough away that they may be easily observed. You

cross-reference visual cues outside the gyroplane with

should be able to see the edges of the selected field

the flight instruments, if available, to maintain a con-

while seated in a normal position and looking out the

stant altitude and angle of bank. Anticipate the roll-out

side of the gyroplane during either a left-hand or right-

by leading the roll-out heading by approximately 20°.

hand course. The distance of the ground track from the

Using section lines or prominent landmarks to aid in

edges of the field should be the same regardless of

orientation can be helpful in rolling out on the proper

whether the course is flown to the left or right. All turns

heading. During roll-out, gradually return the cyclic to

should be started when your gyroplane is abeam the

the original position and reduce power to maintain

corners of the field boundaries. The bank normally

altitude and airspeed.

should not exceed 30°.

COMMON ERRORS

Although the rectangular course may be entered from

any direction, this discussion assumes entry on a down-

Improper bank and power coordination during

wind heading. As you approach the field boundary on

entry and rollout.

the downwind leg, you should begin planning for your

Uncoordinated use of flight controls.

turn to the crosswind leg. Since you have a tailwind on

the downwind leg, the gyroplane’s groundspeed is

Exceeding manufacturer’s recommended maxi-

increased (position 1). During the turn onto the cross-

mum bank angle.

wind leg, which is the equivalent of the base leg in a

Improper technique in correcting altitude

traffic pattern, the wind causes the gyroplane to drift

deviations.

away from the field. To counteract this effect, the roll-

in should be made at a fairly fast rate with a relatively

Loss of orientation.

steep bank (position 2).

Excessive deviation from desired heading during

rollout.

As the turn progresses, the tailwind component

decreases, which decreases the groundspeed.

GROUND REFERENCE MANEUVERS

Consequently, the bank angle and rate of turn must be

Ground reference maneuvers are training exercises

reduced gradually to ensure that upon completion of

flown to help you develop a division of attention

the turn, the crosswind ground track continues to be the

between the flight path and ground references, while

same distance from the edge of the field. Upon comple-

controlling the gyroplane and watching for other

tion of the turn, the gyroplane should be level and

20-8

Start Turn

Enter

No Crab

Pattern

At Boundary

Turn More Than

90°-Roll Out

Complete Turn

With Crab Established

At Boundary

Turn More

Complete Turn

Than 90°

At Boundary

Start Turn

At Boundary

Crab Into

WIND

Wind

Turn less Than

Start Turn

90°-Roll Out

At Boundary

With Crab Established

Complete Turn

Turn Less

At Boundary

Than 90°

Start Turn

At Boundary

Complete Turn

At Boundary

No Crab

Figure 20-10. Rectangular course. The numbered positions in the text refer to the numbers in this illustration.

aligned with the downwind corner of the field.

On the upwind leg, the wind is a headwind, which

However, since the crosswind is now pushing you

results in an decreased groundspeed (position

7).

away from the field, you must establish the proper drift

Consequently, enter the turn onto the next leg with a

correction by flying slightly into the wind. Therefore,

fairly slow rate of roll-in, and a relatively shallow bank

the turn to crosswind should be greater than a 90°

(position 8). As the turn progresses, gradually increase

change in heading (position 3). If the turn has been

the bank angle because the headwind component is

made properly, the field boundary again appears to be

diminishing, resulting in an increasing groundspeed.

one-fourth to one-half mile away. While on the cross-

During and after the turn onto this leg, the wind tends

wind leg, the wind correction should be adjusted, as

to drift the gyroplane toward the field boundary. To

necessary, to maintain a uniform distance from the field

compensate for the drift, the amount of turn must be

boundary (position 4).

less than 90° (position 9).

As the next field boundary is being approached (posi-

Again, the rollout from this turn must be such that as

tion 5), plan the turn onto the upwind leg. Since a wind

the gyroplane becomes level, the nose of the gyroplane

correction angle is being held into the wind and toward

is turned slightly away the field and into the wind to

the field while on the crosswind leg, this next turn

correct for drift. The gyroplane should again be the

requires a turn of less than 90°. Since the crosswind

same distance from the field boundary and at the same

becomes a headwind, causing the groundspeed to

altitude, as on other legs. Continue the crosswind leg

decrease during this turn, the bank initially must be

until the downwind leg boundary is approached (posi-

medium and progressively decreased as the turn pro-

tion 10). Once more you should anticipate drift and

ceeds. To complete the turn, time the rollout so that the

turning radius. Since drift correction was held on the

gyroplane becomes level at a point aligned with the

crosswind leg, it is necessary to turn greater than 90° to

corner of the field just as the longitudinal axis of the

align the gyroplane parallel to the downwind leg

gyroplane again becomes parallel to the field boundary

boundary. Start this turn with a medium bank angle,

(position 6). The distance from the field boundary

gradually increasing it to a steeper bank as the turn pro-

should be the same as on the other sides of the field.

gresses. Time the rollout to assure paralleling the

20-9

boundary of the field as the gyroplane becomes level

used throughout the maneuver since the gyroplane is

(position 11).

headed directly downwind and the groundspeed is at its

highest. Gradually reduce the bank, as necessary, to

If you have a direct headwind or tailwind on the upwind

describe a ground track of a half circle. Time the turn

and downwind leg, drift should not be encountered.

so that as the rollout is completed, the gyroplane is

However, it may be difficult to find a situation where

crossing the reference line perpendicular to it and head-

the wind is blowing exactly parallel to the field bound-

ing directly upwind. Immediately enter a bank in the

aries. This makes it necessary to use a slight wind

opposite direction to begin the second half of the “S.”

correction angle on all the legs. It is important to antici-

Since the gyroplane is now on an upwind heading, this

pate the turns to compensate for groundspeed, drift, and

bank (and the one just completed before crossing the

turning radius. When the wind is behind the gyroplane,

reference line) is the shallowest in the maneuver.

the turn must be faster and steeper; when it is ahead of

Gradually increase the bank, as necessary, to describe a

the gyroplane, the turn must be slower and shallower.

ground track that is a half circle identical in size to the

These same techniques apply while flying in an airport

one previously completed on the other side of the refer-

traffic pattern.

ence line. The steepest bank in this turn should be

attained just prior to rollout when the gyroplane is

S-TURNS

approaching the reference line nearest the downwind

Another training maneuver you might use is the S-turn,

heading. Time the turn so that as the rollout is com-

which helps you correct for wind drift in turns. This

plete, the gyroplane is perpendicular to the reference

maneuver requires turns to the left and right. The refer-

line and is again heading directly downwind.

ence line used, whether a road, railroad, or fence,

should be straight for a considerable distance and

In summary, the angle of bank required at any given

should extend as nearly perpendicular to the wind as

point in the maneuver is dependent on the ground-

possible.

speed. The faster the groundspeed, the steeper the

bank; the slower the groundspeed, the shallower

The object of S-turns is to fly a pattern of two half

the bank. To express it another way, the more nearly

circles of equal size on opposite sides of the reference

the gyroplane is to a downwind heading, the steeper the

line. [Figure

20-11] The maneuver should be

bank; the more nearly it is to an upwind heading, the

performed at a constant altitude of 600 to 1,000 feet

shallower the bank. In addition to varying the angle of

above the terrain. S-turns may be started at any point;

bank to correct for drift in order to maintain the proper

however, during early training it may be beneficial to

radius of turn, the gyroplane must also be flown with a

start on a downwind heading. Entering downwind

drift correction angle (crab) in relation to its ground

permits the immediate selection of the steepest bank

track; except of course, when it is on direct upwind or

downwind headings or there is no wind. One would

normally think of the fore and aft axis of the gyroplane

as being tangent to the ground track pattern at each

Points of

point. However, this is not the case. During the turn on

WIND

Shallowest Bank

the upwind side of the reference line (side from which

the wind is blowing), crab the nose of the gyroplane

toward the outside of the circle. During the turn on the

downwind side of the reference line (side of the refer-

ence line opposite to the direction from which the wind

is blowing), crab the nose of the gyroplane toward the

inside of the circle. In either case, it is obvious that the

Points of

gyroplane is being crabbed into the wind just as it is

Steepest Bank

when trying to maintain a straight ground track. The

amount of crab depends upon the wind velocity and

how nearly the gyroplane is to a crosswind position.

Figure 20-11. S-turns across a road.

The stronger the wind, the greater the crab angle at any

given position for a turn of a given radius. The more

nearly the gyroplane is to a crosswind position, the

that is desired throughout the maneuver. The discus-

greater the crab angle. The maximum crab angle should

sion that follows is based on choosing a reference line

be at the point of each half circle farthest from the

that is perpendicular to the wind and starting the

reference line.

maneuver on a downwind heading.

A standard radius for S-turns cannot be specified, since

As the gyroplane crosses the reference line, immedi-

the radius depends on the airspeed of the gyroplane, the

ately establish a bank. This initial bank is the steepest

20-10

crossroads, or other similar small landmarks are usu-

ally suitable. The point should be in an area away from

WIND

communities, livestock, or groups of people on the

ground to prevent possible annoyance or hazard to

Steeper

others. Since the maneuver is performed between 600

Bank

and 1,000 feet AGL, the area selected should also

afford an opportunity for a safe emergency landing in

the event it becomes necessary.

To enter turns around a point, fly the gyroplane on a

downwind heading to one side of the selected point at a

Shallowest

Steepest

distance equal to the desired radius of turn. When any

Bank

significant wind exists, it is necessary to roll into the

initial bank at a rapid rate so that the steepest bank is

attained abeam the point when the gyroplane is headed

directly downwind. By entering the maneuver while

heading directly downwind, the steepest bank can be

attained immediately. Thus, if a bank of 40° is desired,

Shallower

the initial bank is 40° if the gyroplane is at the correct

Bank

distance from the point. Thereafter, the bank is gradu-

ally shallowed until the point is reached where the

Figure 20-12. Turns around a point.

gyroplane is headed directly upwind. At this point, the

bank is gradually steepened until the steepest bank is

again attained when heading downwind at the initial

velocity of the wind, and the initial bank chosen for

point of entry.

entry.

Just as S-turns require that the gyroplane be turned into

TURNS AROUND A POINT

the wind, in addition to varying the bank, so do turns

This training maneuver requires you to fly constant

around a point. During the downwind half of the circle,

radius turns around a preselected point on the ground

the gyroplane’s nose must be progressively turned

using a maximum bank of approximately 40°, while

toward the inside of the circle; during the upwind half,

maintaining a constant altitude. [Figure 20-12] Your

the nose must be progressively turned toward the out-

objective, as in other ground reference maneuvers, is to

side. The downwind half of the turn around the point

develop the ability to subconsciously control the gyro-

may be compared to the downwind side of the S-turn,

plane while dividing attention between the flight path

while the upwind half of the turn around a point may be

and ground references, while still watching for other

compared to the upwind side of the S-turn.

air traffic in the vicinity.

The factors and principles of drift correction that are

As you become experienced in performing turns

involved in S-turns are also applicable in this maneu-

around a point and have a good understanding of the

ver. As in other ground track maneuvers, a constant

effects of wind drift and varying of the bank angle and

radius around a point will, if any wind exists, require a

wind correction angle, as required, entry into the

constantly changing angle of bank and angles of wind

maneuver may be from any point. When entering this

correction. The closer the gyroplane is to a direct

maneuver at any point, the radius of the turn must be

downwind heading where the groundspeed is greatest,

carefully selected, taking into account the wind veloc-

the steeper the bank, and the faster the rate of turn

ity and groundspeed, so that an excessive bank is not

required to establish the proper wind correction angle.

required later on to maintain the proper ground track.

The more nearly it is to a direct upwind heading where

the groundspeed is least, the shallower the bank, and

COMMON ERRORS DURING GROUND

the slower the rate of turn required to establish

REFERENCE MANEUVERS

the proper wind correction angle. It follows then,

Faulty entry technique.

that throughout the maneuver, the bank and rate of

turn must be gradually varied in proportion to the

Poor planning, orientation, or division of

groundspeed.

attention.

Uncoordinated flight control application.

The point selected for turns around a point should be

prominent and easily distinguishable, yet small enough

Improper correction for wind drift.

to present a precise reference. Isolated trees,

20-11

An unsymmetrical ground track during S-turns

hazardous. Should a go-around become necessary,

across a road.

sufficient altitude to regain airspeed and initiate a climb

may not be available, and ground contact may be

Failure to maintain selected altitude or airspeed.

unavoidable.

Selection of a ground reference where there is no

suitable emergency landing site.

Flight at slow airspeeds is usually conducted at air-

speeds 5 to 10 m.p.h. above the minimum level flight

FLIGHT AT SLOW AIRSPEEDS

airspeed. When flying at slow airspeeds, it is important

The purpose of maneuvering during slow flight is to

that your control inputs be smooth and slow to prevent

help you develop a feel for controlling the gyroplane at

a rapid loss of airspeed due to the high drag increases

slow airspeeds, as well as gain an understanding of how

with small changes in pitch attitude. In addition, turns

load factor, pitch attitude, airspeed, and altitude control

should be limited to shallow bank angles. In order to

relate to each other.

prevent losing altitude during turns, power must be

added. Directional control remains very good while

flying at slow airspeeds, because of the high velocity

Like airplanes, gyroplanes have a specific amount of

slipstream produced by the increased engine power.

power that is required for flight at various airspeeds, and

a fixed amount of power available from the engine. This

Recovery to cruise flight speed is made by lowering

data can be charted in a graph format. [Figure 20-13]

the nose and increasing power. When the desired speed

The lowest point of the power required curve represents

is reached, reduce power to the normal cruise power

the speed at which the gyroplane will fly in level flight

setting.

while using the least amount of power. To fly faster than

this speed, or slower, requires more power. While

COMMON ERRORS

practicing slow flight in a gyroplane, you will likely be

operating in the performance realm on the chart that is

Improper entry technique.

left of the minimum power required speed. This is often

Failure to establish and maintain an appropriate

referred to as the “backside of the power curve,” or

airspeed.

flying “behind the power curve.” At these speeds, as

pitch is increased to slow the gyroplane, more and more

Excessive variations of altitude and heading

power is required to maintain level flight. At the point

when a constant altitude and heading are

where maximum power available is being used, no

specified.

further reduction in airspeed is possible without initiat-

Use of too steep a bank angle.

ing a descent. This speed is referred to as the minimum

level flight speed. Because there is no excess power

Rough or uncoordinated control technique.

available for acceleration, recovery from minimum level

flight speed requires lowering the nose of the gyroplane

HIGH RATE OF DESCENT

and using altitude to regain airspeed. For this reason, it is

A gyroplane will descend at a high rate when flown at

essential to practice slow flight at altitudes that allow

very low forward airspeeds. This maneuver may be

sufficient height for a safe recovery. Unintentionally

entered intentionally when a steep descent is desired,

flying a gyroplane on the backside of the power curve

and can be performed with or without power. An unin-

during approach and landing can be extremely

tentional high rate of descent can also occur as a result

TYPICAL GYROPLANE

Power Required & Power Available vs. Airspeed

Rates of Climb & Descent at Full Throttle

Power

Required

Minimum Level Flight Speed

Engine Power

Available at

Full Throttle

Power Available

for Climb and

Acceleration

Airspeed, MPH

85 Airspeed, MPH

Figure 20-13. The low point on the power required curve is the speed that the gyroplane can fly while using the least amount of

power, and is also the speed that will result in a minimum sink rate in a power-off glide.

20-12

of failing to monitor and maintain proper airspeed. In

apparent during the sensitive maneuvering required

powered flight, if the gyroplane is flown below mini-

for landing, and care must be taken to avoid overcor-

mum level flight speed, a descent results even though

recting for deviations from the desired approach path.

full engine power is applied. Further reducing the air-

After the turn to final, the approach airspeed appropri-

speed with aft cyclic increases the rate of descent. For

ate for the gyroplane should be established. This speed

gyroplanes with a high thrust-to-weight ratio, this

is normally just below the minimum power required

maneuver creates a very high pitch attitude. To recover,

speed for the gyroplane in level flight. During the

the nose of the gyroplane must lowered slightly to

approach, maintain this airspeed by making adjust-

exchange altitude for an increase in airspeed.

ments to the gyroplane’s pitch attitude, as necessary.

Power is used to control the descent rate.

When operating a gyroplane in an unpowered glide,

slowing to below the best glide speed can also result in

Approximately 10 to 20 feet above the runway, begin

a high rate of descent. As airspeed decreases, the rate of

the flare by gradually increasing back pressure on the

descent increases, reaching the highest rate as forward

cyclic to reduce speed and decrease the rate of descent.

speed approaches zero. At slow airspeeds without the

The gyroplane should reach a near-zero rate of descent

engine running, there is very little airflow over the tail

approximately 1 foot above the runway with the power

surfaces and rudder effectiveness is greatly reduced.

at idle. Low airspeed combined with a minimum of

Rudder pedal inputs must be exaggerated to maintain

propwash over the tail surfaces reduces rudder

effective yaw control. To recover, add power, if avail-

effectiveness during the flare. If a yaw moment is

able, or lower the nose and allow the gyroplane to

encountered, use whatever rudder control is required

accelerate to the proper airspeed. This maneuver

to maintain the desired heading. The gyroplane should

demonstrates the importance of maintaining the proper

be kept laterally level and with the longitudinal axis in

glide speed during an engine-out emergency landing.

the direction of ground track. Landing with sideward

Attempting to stretch the glide by raising the nose

motion can damage the landing gear and must be

results in a higher rate of descent at a lower forward

avoided. In a full-flare landing, attempt to hold the

speed, leaving less distance available for the selection

gyroplane just off the runway by steadily increasing

of a landing site.

back pressure on the cyclic. This causes the gyroplane

to settle slowly to the runway in a slightly nose-high

COMMON ERRORS

attitude as forward momentum dissipates.

Improper entry technique.

Ground roll for a full-flare landing is typically under

Failure to recognize a high rate of descent.

50 feet, and touchdown speed under 20 m.p.h. If a 20

Improper use of controls during recovery.

m.p.h. or greater headwind exists, it may be necessary

to decrease the length of the flare and allow the gyro-

Initiation of recovery below minimum recovery

plane to touch down at a slightly higher airspeed to

altitude.

prevent it from rolling backward on landing. After

touchdown, rotor r.p.m. decays rather rapidly. On

LANDINGS

landings where brakes are required immediately after

Landings may be classified according to the landing

touchdown, apply them lightly, as the rotor is still car-

surface, obstructions, and atmospheric conditions.

rying much of the weight of the aircraft and too much

Each type of landing assumes that certain conditions

braking causes the tires to skid.

exist. To meet the actual conditions, a combination of

techniques may be necessary.

SHORT-FIELD LANDING

A short-field landing is necessary when you have a rel-

NORMAL LANDING

atively short landing area or when an approach must be

The procedure for a normal landing in a gyroplane is

made over obstacles that limit the available landing

predicated on having a prepared landing surface and no

area. When practicing short-field landings, assume you

significant obstructions in the immediate area. After

are making the approach and landing over a 50-foot

entering a traffic pattern that conforms to established

obstruction in the approach area.

standards for the airport and avoids the flow of fixed

wing traffic, a before landing checklist should be

reviewed. The extent of the items on the checklist is

To conduct a short-field approach and landing, fol-

dependent on the complexity of the gyroplane, and can

low normal procedures until you are established on

include fuel, mixture, carburetor heat, propeller, engine

the final approach segment. At this point, use aft

instruments, and a check for traffic.

cyclic to reduce airspeed below the speed for mini-

mum sink. By decreasing speed, sink rate increases

Gyroplanes experience a slight lag between control

and a steeper approach path is achieved, minimizing

input and aircraft response. This lag becomes more

the distance between clearing the obstacle and

20-13

making contact with the surface. [Figure 20-14] The

CROSSWIND LANDING

approach speed must remain fast enough, however,

Crosswind landing technique is normally used in gyro-

to allow the flare to arrest the forward and vertical

planes when a crosswind of approximately 15 m.p.h. or

speed of the gyroplane. If the approach speed is too

less exists. In conditions with higher crosswinds, it

low, the remaining vertical momentum will result in

becomes very difficult, if not impossible, to maintain

a hard landing. On a short-field landing with a slight

adequate compensation for the crosswind. In these con-

headwind, a touchdown with no ground roll is possi-

ditions, the slow touchdown speed of a gyroplane

ble. Without wind, the ground roll is normally less

allows a much safer option of turning directly into the

than 50 feet.

wind and landing with little or no ground roll. Deciding

when to use this technique, however, may be

SOFT-FIELD LANDING

complicated by gusting winds or the characteristics of

Use the soft-field landing technique when the landing

the particular landing area.

surface presents high wheel drag, such as mud, snow,

sand, tall grass or standing water. The objective is to

On final approach, establish a crab angle into the wind

transfer the weight of the gyroplane from the rotor to

to maintain a ground track that is aligned with the

the landing gear as gently and slowly as possible. With

extended centerline of the runway. Just before

a headwind close to the touchdown speed of the

touchdown, remove the crab angle and bank the

gyroplane, a power approach can be made close to the

gyroplane slightly into the wind to prevent drift.

minimum level flight speed. As you increase the nose

Maintain longitudinal alignment with the runway using

pitch attitude just prior to touchdown, add additional

the rudder. In higher crosswinds, if full rudder deflec-

power to cushion the landing. However, power should

tion is not sufficient to maintain alignment with the run-

be removed, just as the wheels are ready to touch. This

way, applying a slight amount of power can increase

results is a very slow, gentle touchdown. In a strong

rudder effectiveness. The length of the flare should be

headwind, avoid allowing the gyroplane to roll rear-

reduced to allow a slightly higher touchdown speed than

ward at touchdown. After touchdown, smoothly and

that used in a no-wind landing. Touchdown is made on

gently lower the nosewheel to the ground. Minimize

the upwind main wheel first, with the other main wheel

the use of brakes, and remain aware that the nosewheel

settling to the runway as forward momentum is lost.

could dig in the soft surface.

After landing, continue to keep the rotor tilted into the

wind to maintain positive control during the rollout.

When no wind exists, use a steep approach similar to a

short-field landing so that the forward speed can be dis-

HIGH-ALTITUDE LANDING

sipated during the flare. Use the throttle to cushion the

A high-altitude landing assumes a density altitude near

touchdown.

the limit of what is considered good climb performance

50'

Figure 20-14. The airspeed used on a short-field approach is slower than that for a normal approach, allowing a steeper

approach path and requiring less runway.

20-14

for the gyroplane. When using the same indicated

to go around. Also, the pitch attitude of the gyroplane

airspeed as that used for a normal approach at lower

in the flare is high enough that the tail would be con-

altitude, a high density altitude results in higher rotor

siderably lower than the main gear, and a touch down

r.p.m. and a slightly higher rate of descent. The greater

with power on would result in a sudden pitch down and

vertical velocity is a result of higher true airspeed as

acceleration of the aircraft. Control of the gyroplane

compared with that at low altitudes. When practicing

under these circumstances may be difficult.

high-altitude landings, it is prudent to first learn normal

Consequently, the decision to go around should be

landings with a flare and roll out. Full flare, no roll

made as early as possible, before the speed is reduced

landings should not be attempted until a good feel for

below the point that power required exceeds power

aircraft response at higher altitudes has been acquired.

available.

As with high-altitude takeoffs, it is also important to

consider the effects of higher altitude on engine

COMMON ERRORS

performance.

Failure to recognize a situation where a go-

around is necessary.

COMMON ERRORS DURING LANDING

Improper application of power.

Failure to establish and maintain a stabilized

approach.

Failure to control pitch attitude.

Improper technique in the use of power.

Failure to maintain recommended airspeeds.

Improper technique during flare or touchdown.

Failure to maintain proper track during climb out.

Touchdown at too low an airspeed with strong

headwinds, causing a rearward roll.

AFTER LANDING AND SECURING

The after-landing checklist should include such items

Poor directional control after touchdown.

as the transponder, cowl flaps, fuel pumps, lights, and

Improper use of brakes.

magneto checks, when so equipped. The rotor blades

demand special consideration after landing, as turning

GO-AROUND

rotor blades can be hazardous to others. Never enter an

The go-around is used to abort a landing approach

area where people or obstructions are present with the

when unsafe factors for landing are recognized. If the

rotor turning. To assist the rotor in slowing, tilt the

decision is made early in the approach to go around,

cyclic control into the prevailing wind or face the gyro-

normal climb procedures utilizing V_X and V_Y should

plane downwind. When slowed to under approximately

be used. A late decision to go around, such as after the

75 r.p.m., the rotor brake may be applied, if available.

full flare has been initiated, may result in an airspeed

Use caution as the rotor slows, as excess taxi speed or

where power required is greater than power available.

high winds could cause blade flap to occur. The blades

When this occurs, a touchdown becomes unavoidable

should be depitched when taxiing if a collective control

and it may be safer to proceed with the landing than to

is available. When leaving the gyroplane, always

sustain an extended ground roll that would be required

secure the blades with a tiedown or rotor brake.

20-15

Gyroplanes are quite reliable, however emergencies do

safe takeoff, but having this distance available does not

occur, whether a result of mechanical failure or pilot

necessarily guarantee a safe aborted takeoff is possible

error. By having a thorough knowledge of the

for every situation. If the decision to abort is made after

gyroplane and its systems, you will be able to more

liftoff, for example, the gyroplane will require consid-

readily handle the situation. In addition, by knowing

erably more distance to stop than the accelerate/stop

the conditions which can lead to an emergency, many

figure, which only considers the ground roll require-

potential accidents can be avoided.

ment. Planning a course of action for an abort decision

at various stages of the takeoff is the best way to ensure

the gyroplane can be brought safely to a stop should the

ABORTED TAKEOFF

need arise.

Prior to every takeoff, consideration must be given to a

course of action should the takeoff become undesirable

For a gyroplane without a flight manual or other pub-

or unsafe. Mechanical failures, obstructions on the

lished performance data, the accelerate/stop distance

takeoff surface, and changing weather conditions are

can be reasonably estimated once you are familiar with

all factors that could compromise the safety of a take-

the performance and takeoff characteristics of the air-

off and constitute a reason to abort. The decision to

craft. For a more accurate figure, you can accelerate the

abort a takeoff should be definitive and made as soon

gyroplane to takeoff speed, then slow to a stop, and

as an unsafe condition is recognized. By initiating the

note the distance used. Doing this several times gives

abort procedures early, more time and distance will be

you an average accelerate/stop distance. When per-

available to bring the gyroplane to a stop. A late deci-

formance charts for the aircraft are available, as in the

sion to abort, or waiting to see if it will be necessary to

flight manual of a certificated gyroplane, accurate

abort, can result in a dangerous situation with little time

accelerate/stop distances under various conditions can

to respond and very few options available.

be determined by referring to the ground roll informa-

tion contained in the charts.

When initiating the abort sequence prior to the

gyroplane leaving the surface, the procedure is quite

simple. Reduce the throttle to idle and allow the

LIFT-OFF AT LOW AIRSPEED AND

gyroplane to decelerate, while slowly applying aft

HIGH ANGLE OF ATTACK

cyclic for aerodynamic braking. This technique pro-

Because of ground effect, your gyroplane might be able

vides the most effective braking and slows the aircraft

to become airborne at an airspeed less than minimum

very quickly. If the gyroplane has left the surface when

level flight speed. In this situation, the gyroplane is fly-

the decision to abort is made, reduce the throttle until

ing well behind the power curve and at such a high

an appropriate descent rate is achieved. Once contact

angle of attack that unless a correction is made, there

with the surface is made, reduce the throttle to idle and

will be little or no acceleration toward best climb

apply aerodynamic braking as before. The wheel

speed. This condition is often encountered in

brakes, if the gyroplane is so equipped, may be applied,

gyroplanes capable of jump takeoffs. Jumping without

as necessary, to assist in slowing the aircraft.

sufficient rotor inertia to allow enough time to acceler-

ate through minimum level flight speed, usually results

ACCELERATE/STOP DISTANCE

in your gyroplane touching down after liftoff. If you do

An accelerate/stop distance is the length of ground roll

touch down after performing a jump takeoff, you

an aircraft would require to accelerate to takeoff speed

should abort the takeoff.

and, assuming a decision to abort the takeoff is made,

bring the aircraft safely to a stop. This value changes

During a rolling takeoff, if the gyroplane is forced into

for a given aircraft based on atmospheric conditions,

the air too early, you could get into the same situation.

the takeoff surface, aircraft weight, and other factors

It is important to recognize this situation and take

affecting performance. Knowing the accelerate/stop

immediate corrective action. You can either abort the

value for your gyroplane can be helpful in planning a

takeoff, if enough runway exists, or lower the nose and

21-1

accelerate to the best climb speed. If you choose to con-

As with most other rotor-wing aircraft, gyroplanes

tinue the takeoff, verify that full power is applied, then,

experience a slight delay between control input and the

slowly lower the nose, making sure the gyroplane does

reaction of the aircraft. This delay may cause an inex-

not contact the surface. While in ground effect, acceler-

perienced pilot to apply more control input than

ate to the best climb speed. Then, adjust the nose pitch

required, causing a greater aircraft response than was

attitude to maintain that airspeed.

desired. Once the error has been recognized, opposite

control input is applied to correct the flight attitude.

COMMON ERRORS

Because of the nature of the delay in aircraft response,

The following errors might occur when practicing a

it is possible for the corrections to be out of synchro-

lift-off at a low airspeed.

nization with the movements of the aircraft and aggra-

vate the undesired changes in attitude. The result is

Failure to check rotor for proper operation, track,

PIO, or unintentional oscillations that can grow rapidly

and r.p.m. prior to initiating takeoff.

in magnitude. [Figure 21-1]

Use of a power setting that does not simulate a

“behind the power curve” situation.

In gyroplanes with an open cockpit and limited flight

instruments, it can be difficult for an inexperienced

Poor directional control.

pilot to recognize a level flight attitude due to the lack

Rotation at a speed that is inappropriate for the

of visual references. As a result, PIO can develop as the

maneuver.

pilot chases a level flight attitude and introduces climb-

ing and descending oscillations. PIO can also develop

Poor judgement in determining whether to abort

if a wind gust displaces the aircraft, and the control

or continue takeoff.

inputs made to correct the attitude are out of phase with

Failure to establish and maintain proper climb

the aircraft movements. Because the rotor disc angle

attitude and airspeed, if takeoff is continued.

decreases at higher speeds and cyclic control becomes

more sensitive, PIO is more likely to occur and can be

Not maintaining the desired ground track during

more pronounced at high airspeeds. To minimize the

the climb.

possibility of PIO, avoid high-speed flight in gusty

conditions, and make only small control inputs. After

PILOT-INDUCED OSCILLATION (PIO)

making a control input, wait briefly and observe the

Pilot-induced oscillation, sometimes referred to as por-

reaction of the aircraft before making another input. If

poising, is an unintentional up-and-down oscillation of

PIO is encountered, reduce power and place the cyclic

the gyroplane accompanied with alternating climbs and

in the position for a normal climb. Once the oscillations

descents of the aircraft. PIO is often the result of an

have stopped, slowly return the throttle and cyclic to

inexperienced pilot overcontrolling the gyroplane, but

their normal positions. The likelihood of encountering

this condition can also be induced by gusty wind con-

PIO decreases greatly as experience is gained, and the

ditions. While this condition is usually thought of as a

ability to subconsciously anticipate the reactions of the

longitudinal problem, it can also happen laterally.

gyroplane to control inputs is developed.

Gyroplane

reacts

Variance from desired

Gyroplane

Overcorrection recognized,

Overcorrection

flight path recognized,

reacts

larger input control made

recognized, larger

control input made

to correct

control input made

to correct

Gyroplane

reacts

Normal

Flight

Figure 21-1. Pilot-induced oscillation can result if the gyroplane’s reactions to control inputs are not anticipated and become

out of phase.

21-2

imbalance causing the rotor center of gravity to rotate

BUNTOVER (POWER PUSHOVER)

around the hub. This phenomenon is not unlike an out-

As you learned in Chapter

16-Gyroplane

of-balance washing machine. [Figure 21-2]

Aerodynamics, the stability of a gyroplane is greatly

influenced by rotor force. If rotor force is rapidly

removed, some gyroplanes have a tendency to pitch

forward abruptly. This is often referred to as a forward

Rotor

Center of Gravity

tumble, buntover, or power pushover. Removing the

rotor force is often referred to as unloading the rotor,

122°

and can occur if pilot-induced oscillations become

excessive, if extremely turbulent conditions are

encountered, or the nose of the gyroplane is pushed for-

ward rapidly after a steep climb.

A power pushover can occur on some gyroplanes that

have the propeller thrust line above the center of grav-

ity and do not have an adequate horizontal stabilizer. In

this case, when the rotor is unloaded, the propeller

Figure 21-2. Taxiing on rough terrain can send a shock wave

thrust magnifies the pitching moment around the center

to the rotor system, resulting in the blades of a three-bladed

of gravity. Unless a correction is made, this nose

rotor system moving from their normal 120° relationship to

pitching action could become self-sustaining and

each other.

irreversible. An adequate horizontal stabilizer slows the

pitching rate and allows time for recovery.

To reduce the chance of experiencing ground reso-

Since there is some disagreement between manufactur-

nance, every preflight should include a check for

ers as to the proper recovery procedure for this

proper strut inflation, tire pressure, and lag-lead

situation, you must check with the manufacturer of

damper operation. Improper strut or tire inflation can

your gyroplane. In most cases, you need to remove

change the vibration frequency of the airframe, while

power and load the rotor blades. Some manufacturers,

improper damper settings change the vibration fre-

especially those with gyroplanes where the propeller

quency of the rotor.

thrust line is above the center of gravity, recommend that

you need to immediately remove power in order to pre-

If you experience ground resonance, and the rotor

vent a power pushover situation. Other manufacturers

r.p.m. is not yet sufficient for flight, apply the rotor

recommend that you first try to load the rotor blades. For

brake to maximum and stop the rotor as soon as possi-

the proper positioning of the cyclic when loading up the

ble. If ground resonance occurs during takeoff, when

rotor blades, check with the manufacturer.

rotor r.p.m. is sufficient for flight, lift off immediately.

Ground resonance cannot occur in flight, and the rotor

When compared to other aircraft, the gyroplane is just

blades will automatically realign themselves once the

as safe and very reliable. The most important factor, as

gyroplane is airborne. When prerotating the rotor sys-

in all aircraft, is pilot proficiency. Proper training and

tem prior to takeoff, a slight vibration may be felt that

flight experience helps prevent the risks associated

is a very mild form of ground resonance. Should this

with pilot-induced oscillation or buntover.

oscillation amplify, discontinue the prerotation and

apply maximum rotor brake.

GROUND RESONANCE

Ground resonance is a potentially damaging aerody-

EMERGENCY APPROACH AND

namic phenomenon associated with articulated rotor

LANDING

systems. It develops when the rotor blades move out of

The modern engines used for powering gyroplanes are

phase with each other and cause the rotor disc to

generally very reliable, and an actual mechanical mal-

become unbalanced. If not corrected, ground resonance

function forcing a landing is not a common occurrence.

can cause serious damage in a matter of seconds.

Failures are possible, which necessitates planning for

and practicing emergency approaches and landings.

Ground resonance can only occur while the gyroplane

The best way to ensure that important items are not

is on the ground. If a shock is transmitted to the rotor

overlooked during an emergency procedure is to use a

system, such as with a hard landing on one gear or

checklist, if one is available and time permits. Most

when operating on rough terrain, one or more of the

gyroplanes do not have complex electrical, hydraulic,

blades could lag or lead and allow the rotor system’s

or pneumatic systems that require lengthy checklists.

center of gravity to be displaced from the center of rota-

In these aircraft, the checklist can be easily committed

tion. Subsequent shocks to the other gear aggravate the

to memory so that immediate action can be taken if

21-3

needed. In addition, you should always maintain an

smaller area than would normally be considered. On

awareness of your surroundings and be constantly on

landing, use short or soft field technique, as appropri-

the alert for suitable emergency landing sites.

ate, for the site selected. A slightly higher-than-normal

approach airspeed may be required to maintain ade-

When an engine failure occurs at altitude, the first

quate airflow over the rudder for proper yaw control.

course of action is to adjust the gyroplane’s pitch atti-

tude to achieve the best glide speed. This yields the

EMERGENCY EQUIPMENT AND

most distance available for a given altitude, which in

SURVIVAL GEAR

turn, allows for more possible landing sites. A common

On any flight not in the vicinity of an airport, it is

mistake when learning emergency procedures is

highly advisable to prepare a survival kit with items

attempting to stretch the glide by raising the nose,

that would be necessary in the event of an emergency.

which instead results in a steep approach path at a slow

A properly equipped survival kit should be able to

airspeed and a high rate of descent. [Figure 21-3] Once

provide you with sustenance, shelter, medical care, and

you have attained best glide speed, scan the area within

a means to summon help without a great deal of effort

gliding distance for a suitable landing site. Remember

on your part. An efficient way to organize your survival

to look behind the aircraft, as well as in front, making

kit is to prepare a basic core of supplies that would be

gentle turns, if necessary, to see around the airframe.

necessary for any emergency, and allow additional

When selecting a landing site, you must consider the

space for supplementary items appropriate for the

wind direction and speed, the size of the landing site,

terrain and weather you expect for a particular flight.

obstructions to the approach, and the condition of the

The basic items to form the basis of your survival kit

surface. A site that allows a landing into the wind and

would typically include: a first-aid kit and field

has a firm, smooth surface with no obstructions is the

medical guide, a flashlight, water, a knife, matches,

most desirable. When considering landing on a road, be

some type of shelter, and a signaling device. Additional

alert for powerlines, signs, and automobile traffic. In

items that may be added to meet the conditions, for

many cases, an ideal site will not be available, and it

example, would be a lifevest for a flight over water, or

will be necessary for you to evaluate your options and

heavy clothing for a flight into cold weather. Another

choose the best alternative. For example, if a steady

consideration is carrying a cellular phone. Several

wind will allow a touchdown with no ground roll, it

pilots have been rescued after calling someone to

may be acceptable to land in a softer field or in a

indicate there had been an accident.

Figure 21-3. Any deviation from best glide speed will reduce the distance you can glide and may cause you to land short of a

safe touchdown point.

21-4

As with any aircraft, the ability to pilot a gyroplane

assembled at home. This makes the airworthiness of

safely is largely dependent on the capacity of the pilot

these gyroplanes ultimately dependent on the vigilance

to make sound and informed decisions. To this end,

of the one assembling and maintaining the aircraft.

techniques have been developed to ensure that a pilot

Consider the following scenario.

uses a systematic approach to making decisions, and

that the course of action selected is the most appropri-

Jerry recently attended an airshow that had a gyro-

ate for the situation. In addition, it is essential that you

plane flight demonstration and a number of gyroplanes

learn to evaluate your own fitness, just as you evaluate

on display. Being somewhat mechanically inclined and

the airworthiness of your aircraft, to ensure that your

retired with available spare time, Jerry decided that

physical and mental condition is compatible with a safe

building a gyroplane would be an excellent project for

flight. The techniques for acquiring these essential

him and ordered a kit that day. When the kit arrived,

skills are explained in depth in Chapter

14-

Jerry unpacked it in his garage and immediately began

Aeronautical Decision Making (Helicopter).

the assembly. As the gyroplane neared completion,

Jerry grew more excited at the prospect of flying an air-

As explained in Chapter 14, one of the best methods to

craft that he had built with his own hands. When the

develop your aeronautical decision making is learning

gyroplane was nearly complete, Jerry noticed that a

to recognize the five hazardous attitudes, and how to

rudder cable was missing from the kit, or perhaps lost

counteract these attitudes. [Figure 22-1] This chapter

during the assembly. Rather than contacting the manu-

focuses on some examples of how these hazardous atti-

facturer and ordering a replacement, which Jerry

tudes can apply to gyroplane operations.

thought would be a hassle and too time consuming, he

went to his local hardware store and purchased some

HAZARDOUS ATTITUDE

ANTIDOTE

cable he thought would work. Upon returning home, he

was able to fashion a rudder cable that seemed func-

Impulsivity:

tional and continued with the assembly.

"Do something-quickly!"

"Not so fast. Think first."

Invulnerability:

Jerry is exhibiting “impulsivity.” Rather than taking the

"It won't happen to me!"

"It could happen to me."

time to properly build his gyroplane to the specifica-

Macho:

tions set forth by the manufacturer, Jerry let his

"I can do it."

"Taking chances is foolish."

excitement allow him to cut corners by acting on

impulse, rather than taking the time to think the matter

Resignation:

"I'm not helpless. I can make the

through. Although some enthusiasm is normal during

"What's the use?"

difference."

assembly, it should not be permitted to compromise the

airworthiness of the aircraft. Manufacturers often use

Anti-authority:

"Follow the rules. They are

high quality components, which are constructed and

"Don't tell me!"

usually right."

tested to standards much higher than those found in

hardware stores. This is particularly true in the area of

Figure 22-1. To overcome hazardous attitudes, you must

cables, bolts, nuts, and other types of fasteners where

memorize the antidotes for each of them. You should know

strength is essential. The proper course of action Jerry

them so well that they will automatically come to mind when

should have taken would be to stop, think, and consider

you need them.

the possible consequences of making an impulsive

decision. Had he realized that a broken

IMPULSIVITY

rudder cable in flight could cause a loss of control of

Gyroplanes are a class of aircraft which can be acquired,

the gyroplane, he likely would have taken the time to

constructed, and operated in ways unlike most other air-

contact the manufacturer and order a cable that met the

craft. This inspires some of the most exciting and

design specifications.

rewarding aspects of flying, but it also creates a unique

set of dangers to which a gyroplane pilot must be alert.

INVULNERABILITY

For example, a wide variety of amateur-built gyroplanes

Another area that can often lead to trouble for a gyro-

are available, which can be purchased in kit form and

plane pilots is the failure to obtain adequate flight

22-1

instruction to operate their gyroplane safely. This can

tempted to operate progressively closer to the edge of

be the result of people thinking that because they can

the safe operating envelope. Consider the following

build the machine themselves, it must be simple

scenario.

enough to learn how to fly by themselves. Other

reasons that can lead to this problem can be simply

Pat has been flying gyroplanes for years and has an

monetary, in not wanting to pay the money for adequate

excellent reputation as a skilled pilot. He has recently

instruction, or feeling that because they are qualified in

built a high performance gyroplane with an advanced

another type of aircraft, flight instruction is not neces-

rotor system. Pat was excited to move into a more

sary. In reality, gyroplane operations are quite unique,

advanced aircraft because he had seen the same design

and there is no substitute for adequate training by a

performing aerobatics in an airshow earlier that year.

competent and authorized instructor. Consider the

He was amazed by the capability of the machine. He

following scenario.

had always felt that his ability surpassed the capability

of the aircraft he was flying. He had invested a large

amount of time and resources into the construction of

Jim recently met a coworker who is a certified pilot and

the aircraft, and, as he neared completion of the assem-

owner of a two-seat gyroplane. In discussing the gyro-

bly, he was excited about the opportunity of showing

plane with his coworker, Jim was fascinated and

his friends and family his capabilities.

reminded of his days in the military as a helicopter

pilot many years earlier. When offered a ride, Jim read-

During the first few flights, Pat was not completely

ily accepted. He met his coworker at the airport the

comfortable in the new aircraft, but he felt that he was

following weekend for a short flight and was immedi-

progressing through the transition at a much faster

ately hooked. After spending several weeks researching

pace than the average pilot. One morning, when he was

available designs, Jim decided on a particular

with some of his fellow gyroplane enthusiasts, Pat

gyroplane and purchased a kit. He had it assembled in

began to brag about the superior handling qualities of

a few months, with the help and advice of his new friend

the machine he had built. His friends were very excited,

and fellow gyroplane enthusiast. When the gyroplane

and Pat realized that they would be expecting quite a

was finally finished, Jim asked his friend to take him

show on his next flight. Not wanting to disappoint them,

for a ride in his two-seater to teach him the basics of

he decided that although it might be early, he would

flying. The rest, he said, he would figure out while

give the spectators on the ground a real show. On his

flying his own machine from a landing strip that he had

first pass he came down fairly steep and fast and recov-

fashioned in a field behind his house.

ered from the dive with ease. Pat then decided to make

another pass only this time he would come in much

Jim is unknowingly inviting disaster by allowing him-

steeper. As he began to recover, the aircraft did not

self to be influenced by the hazardous attitude of

climb as he expected and almost settled to the ground.

“invulnerability.” Jim does not feel that it is possible to

Pat narrowly escaped hitting the spectators as he was

have an accident, probably because of his past experi-

trying to recover from the dive.

ence in helicopters and from witnessing the ease with

which his coworker controlled the gyroplane on their

Pat had let the “macho” hazardous attitude influence

flight together. What Jim is failing to consider, how-

his decision making. He could have avoided the conse-

ever, is the amount of time that has passed since he was

quences of this attitude if he had stopped to think that

proficient in helicopters, and the significant differences

taking chances is foolish.

between helicopter and gyroplane operations. He is

also overlooking the fact that his friend is a certificated

RESIGNATION

pilot, who has taken a considerable amount of instruc-

Some of the elements pilots face cannot be controlled.

tion to reach his level of competence. Without adequate

Although we cannot control the weather, we do have

instruction and experience, Jim could, for example,

some very good tools to help predict what it will do,

find himself in a pilot-induced oscillation without

and how it can affect our ability to fly safely. Good

knowing the proper technique for recovery, which

pilots always make decisions that will keep their

could ultimately be disastrous. The antidote for an

options open if an unexpected event occurs while

attitude of invulnerability is to realize that accidents

flying. One of the greatest resources we have in the

can happen to anyone.

cockpit is the ability to improvise and improve the

overall situation even when a risk element jeopardizes

MACHO

the probability of a successful flight. Consider the fol-

Due to their unique design, gyroplanes are quite

lowing scenario.

responsive and have distinct capabilities. Although

gyroplanes are capable of incredible maneuvers, they

Judi flies her gyroplane out of a small grass strip on

do have limitations. As gyroplane pilots grow more

her family’s ranch. Although the rugged landscape of

comfortable with their machines, they might be

the ranch lends itself to the remarkable scenery, it

22-2

leaves few places to safely land in the event of an emer-

regulations, or on the ragged edge, eventually get

gency. The only suitable place to land other than the

caught, or even worse, they end up having an accident.

grass strip is to the west on a smooth section of the road

Consider the following scenario.

leading to the house. During Judi’s training, her traffic

patterns were always made with left turns. Figuring

Dick is planning to fly the following morning and real-

this was how she was to make all traffic patterns, she

izes that his medical certificate has expired. He knows

applied this to the grass strip at the ranch. In addition,

that he will not have time to take a flight physical

she was uncomfortable with making turns to the right.

before his morning flight. Dick thinks to himself “The

Since, the wind at the ranch was predominately from

rules are too restrictive. Why should I spend the time

the south, this meant that the traffic pattern was to the

and money on a physical when I will be the only one at

east of the strip.

risk if I fly tomorrow?”

Judi’s hazardous attitude is “resignation.” She has

Dick decides to fly the next morning thinking that no

accepted the fact that her only course of action is to fly

harm will come as long as no one finds out that he is

east of the strip, and if an emergency happens, there is

flying illegally. He pulls his gyroplane out from the

not much she can do about it. The antidote to this

hangar, does the preflight inspection, and is getting

hazardous attitude is “I’m not helpless, I can make a dif-

ready to start the engine when an FAA inspector walks

ference.” Judi could easily modify her traffic pattern so

up and greets him. The FAA inspector is conducting a

that she is always within gliding distance of a

random inspection and asks to see Dick’s pilot and

suitable landing area. In addition, if she was uncomfort-

medical certificates.

able with a maneuver, she could get additional training.

Dick subjected himself to the hazardous attitude of “anti-

ANTI-AUTHORITY

authority.” Now, he will be unable to fly, and has invited

Regulations are implemented to protect aviation

an exhaustive review of his operation by the FAA. Dick

personnel as well as the people who are not involved in

could have prevented this event if had taken the time to

aviation. Pilots who choose to operate outside of the

think, “Follow the rules. They are usually right.”

22-3

GLOSSARY

ABSOLUTE ALTITUDE-The act-

ANGLE OF ATTACK-The angle

BLADE FLAP-The ability of the

ual distance an object is above the

between the airfoil’s chord line and

rotor blade to move in a vertical direc-

ground.

the relative wind.

tion. Blades may flap independently

or in unison.

ADVANCING BLADE-The blade

ANTITORQUE PEDAL-The pedal

moving in the same direction as the

used to control the pitch of the tail

BLADE GRIP-The part of the hub

helicopter or gyroplane. In rotorcraft

rotor or air diffuser in a NOTAR®

assembly to which the rotor blades are

that have counterclockwise main rotor

system.

attached, sometimes referred to as

blade rotation as viewed from above,

blade forks.

the advancing blade is in the right half

ANTITORQUE ROTOR-See tail

of the rotor disc area during forward

BLADE LEAD OR LAG-The fore

rotor.

movement.

and aft movement of the blade in the

plane of rotation. It is sometimes

ARTICULATED ROTOR-A rotor

called hunting or dragging.

AIRFOIL-Any surface designed to

system in which each of the blades is

obtain a useful reaction of lift, or neg-

connected to the rotor hub in such a

BLADE LOADING-The load

ative lift, as it moves through the air.

way that it is free to change its pitch

imposed on rotor blades, determined

angle, and move up and down and

by dividing the total weight of the hel-

AGONIC LINE-A line along which

fore and aft in its plane of rotation.

icopter by the combined area of all the

there is no magnetic variation.

rotor blades.

AUTOPILOT-Those units and

AIR DENSITY-The density of the

components that furnish a means of

BLADE ROOT-The part of the

air in terms of mass per unit volume.

automatically controlling the aircraft.

blade that attaches to the blade grip.

Dense air has more molecules per unit

volume than less dense air. The densi-

AUTOROTATION-The condition

BLADE SPAN-The length of a

ty of air decreases with altitude above

of flight during which the main rotor

blade from its tip to its root.

the surface of the earth and with

is driven only by aerodynamic forces

increasing temperature.

with no power from the engine.

BLADE STALL-The condition of

the rotor blade when it is operating at

AIRCRAFT PITCH-When refer-

AXIS-OF-ROTATION-The imagi-

an angle of attack greater than the

enced to an aircraft, it is the move-

nary line about which the rotor

maximum angle of lift.

ment about its lateral, or pitch axis.

rotates. It is represented by a line

Movement of the cyclic forward or aft

drawn through the center of, and per-

BLADE TIP-The further most part

causes the nose of the helicopter or

pendicular to, the tip-path plane.

of the blade from the hub of the rotor.

gyroplane to pitch up or down.

BASIC EMPTY WEIGHT-The

BLADE TRACK-The relationship

AIRCRAFT ROLL-Is the move-

weight of the standard rotorcraft,

of the blade tips in the plane of rota-

ment of the aircraft about its

operational equipment, unusable fuel,

tion. Blades that are in track will move

longitudinal axis. Movement of the

and full operating fluids, including

through the same plane of rotation.

cyclic right or left causes the helicop-

full engine oil.

ter or gyroplane to tilt in that direction.

BLADE TRACKING-The mechan-

BLADE CONING-An upward

ical procedure used to bring the blades

AIRWORTHINESS DIRECTIVE

sweep of rotor blades as a result of lift

of the rotor into a satisfactory relation-

-When an unsafe condition exists

and centrifugal force.

ship with each other under dynamic

with an aircraft, the FAA issues an air-

conditions so that all blades rotate on a

worthiness directive to notify con-

BLADE DAMPER-A device

common plane.

cerned parties of the condition and to

attached to the drag hinge to restrain

describe the appropriate corrective

the fore and aft movement of the rotor

BLADE TWIST-The variation in

action.

blade.

the angle of incidence of a blade

between the root and the tip.

ALTIMETER-An instrument that

BLADE FEATHER OR FEATH-

indicates flight altitude by sensing

ERING-The rotation of the blade

BLOWBACK-The tendency of the

pressure changes and displaying alti-

around the spanwise (pitch change)

rotor disc to tilt aft in forward flight as

tude in feet or meters.

axis.

a result of flapping.

G-1

BUNTOVER-The tendency of a

COLLECTIVE PITCH CON-

DISC AREA-The area swept by the

gyroplane to pitch forward when rotor

TROL-The control for changing the

blades of the rotor. It is a circle with

force is removed.

pitch of all the rotor blades in the main

its center at the hub and has a radius of

rotor system equally and simultane-

one blade length.

CALIBRATED AIRSPEED (CAS)

ously and, consequently, the amount

-Indicated airspeed of an aircraft,

of lift or thrust being generated.

DISC LOADING-The total heli-

corrected for installation and instru-

copter weight divided by the rotor disc

mentation errors.

CONING-See blade coning.

area.

CENTER OF GRAVITY-The the-

CORIOLIS EFFECT-The tenden-

DISSYMMETRY OF LIFT-The

oretical point where the entire weight

cy of a rotor blade to increase or

unequal lift across the rotor disc

of the helicopter is considered to be

decrease its velocity in its plane of

resulting from the difference in the

concentrated.

rotation when the center of mass

velocity of air over the advancing

moves closer or further from the axis

blade half and retreating blade half of

of rotation.

the rotor disc area.

CENTER OF PRESSURE-The

point where the resultant of all the

CYCLIC FEATHERING-The

DRAG-An aerodynamic force on a

aerodynamic forces acting on an air-

mechanical change of the angle of

body acting parallel and opposite to

foil intersects the chord.

incidence, or pitch, of individual rotor

relative wind.

blades independently of other blades

CENTRIFUGAL FORCE-The

in the system.

DUAL ROTOR-A rotor system uti-

apparent force that an object moving

lizing two main rotors.

along a circular path exerts on the

CYCLIC PITCH CONTROL-The

body constraining the object and that

control for changing the pitch of each

DYNAMIC ROLLOVER-The ten-

acts outwardly away from the center

rotor blade individually as it rotates

dency of a helicopter to continue

of rotation.

through one cycle to govern the tilt of

rolling when the critical angle is

the rotor disc and, consequently, the

exceeded, if one gear is on the ground,

CENTRIPETAL

FORCE-The

direction and velocity of horizontal

and the helicopter is pivoting around

force that attracts a body toward its

movement.

that point.

axis of rotation. It is opposite centrifu-

gal force.

DELTA HINGE-A flapping hinge

FEATHERING-The action that

with a skewed axis so that the flapping

changes the pitch angle of the rotor

CHIP DETECTOR-A warning

motion introduces a component of

blades by rotating them around their

device that alerts you to any abnormal

feathering that would result in a restor-

feathering (spanwise) axis.

wear in a transmission or engine. It

ing force in the flap-wise direction.

consists of a magnetic plug located

FEATHERING AXIS-The axis

within the transmission. The magnet

DENSITY ALTITUDE-Pressure

about which the pitch angle of a rotor

attracts any metal particles that have

altitude corrected for nonstandard

blade is varied. Sometimes referred to

come loose from the bearings or other

temperature variations.

as the spanwise axis.

transmission parts. Most chip detec-

tors have warning lights located on the

instrument panel that illuminate when

DEVIATION-A compass error

FEEDBACK-The transmittal of

metal particles are picked up.

caused by magnetic disturbances from

forces, which are initiated by aerody-

the electrical and metal components in

namic action on rotor blades, to the

the aircraft. The correction for this

cockpit controls.

CHORD-An imaginary straight line

error is displayed on a compass cor-

between the leading and trailing edges

rection card place near the magnetic

FLAPPING HINGE-The hinge

of an airfoil section.

compass of the aircraft.

that permits the rotor blade to flap and

thus balance the lift generated by the

CHORDWISE AXIS-A term used

DIRECT CONTROL-The ability

advancing and retreating blades.

in reference to semirigid rotors

describing the flapping or teetering

to maneuver a rotorcraft by tilting the

axis of the rotor.

rotor disc and changing the pitch of

FLAPPING-The vertical move-

the rotor blades.

ment of a blade about a flapping

COAXIL ROTOR-A rotor system

hinge.

utilizing two rotors turning in opposite

DIRECT SHAFT TURBINE-A

directions on the same centerline. This

shaft turbine engine in which the com-

FLARE-A maneuver accomplished

system is used to eliminated the need

pressor and power section are mount-

prior to landing to slow down a rotor-

for a tail rotor.

ed on a common driveshaft.

craft.

G-2

FREE TURBINE-A turboshaft

tion and communication with other

LIFT-One of the four main forces

engine with no physical connection

participants in the aviation communi-

acting on a rotorcraft. It acts perpendi-

between the compressor and power

ty, such as other crew members and air

cular to the relative wind.

output shaft.

traffic control personnel.

LOAD FACTOR-The ratio of a

HUNTING-Movement of a blade

specified load to the total weight of

FREEWHEELING UNIT-A com-

with respect to the other blades in the

the aircraft.

ponent of the transmission or power

plane of rotation, sometimes called

train that automatically disconnects

the main rotor from the engine when

leading or lagging.

MARRIED NEEDLES-A term

the engine stops or slows below the

used when two hands of an instrument

equivalent rotor r.p.m.

INERTIA-The property of matter

are superimposed over each other, as

by which it will remain at rest or in a

on the engine/rotor tachometer.

state of uniform motion in the same

FULLY ARTICULATED ROTOR

direction unless acted upon by some

MAST-The component that sup-

SYSTEM-See articulated rotor sys-

external force.

ports the main rotor.

tem.

IN GROUND EFFECT (IGE)

MAST BUMPING-Action of the

GRAVITY-See weight.

HOVER-Hovering close to the sur-

rotor head striking the mast, occurring

face (usually less than one rotor diam-

on underslung rotors only.

GROSS WEIGHT-The sum of the

eter distance above the surface) under

basic empty weight and useful load.

the influence of ground effect.

MINIMUM LEVEL FLIGHT

SPEED-The speed below which a

GROUND EFFECT-A usually

INDUCED DRAG-That part of the

gyroplane, the propeller of which is

beneficial influence on rotorcraft per-

total drag that is created by the pro-

producing maximum thrust, loses alti-

formance that occurs while flying

duction of lift.

tude.

close to the ground. It results from a

reduction in upwash, downwash, and

INDUCED FLOW-The component

NAVIGATIONAL AID (NAVAID)

bladetip vortices, which provide a cor-

of air flowing vertically through the

-Any visual or electronic device, air-

responding decrease in induced drag.

rotor system resulting from the pro-

borne or on the surface, that provides

duction of lift.

point-to-point guidance information,

GROUND RESONANCE-Self-

or position data, to aircraft in flight.

excited vibration occurring whenever

ISOGONIC LINES-Lines on

the frequency of oscillation of the

charts that connect points of equal

NIGHT-The time between the end

blades about the lead-lag axis of an

magnetic variation.

of evening civil twilight and the

articulated rotor becomes the same as

beginning of morning civil twilight, as

the natural frequency of the fuselage.

KNOT-A unit of speed equal to one

published in the American Air

nautical mile per hour.

Almanac.

GYROCOPTER-Trademark

L/DMAX-The maximum ratio

applied to gyroplanes designed and

NORMALLY ASPIRATED ENGINE

produced by the Bensen Aircraft

between total lift (L) and total drag

-An engine that does not compen-

Company.

(D). This point provides the best glide

sate for decreases in atmospheric pres-

speed. Any deviation from the best

sure through turbocharging or other

GYROSCOPIC PRECESSION-

glide speed increases drag and reduces

means.

An inherent quality of rotating bodies,

the distance you can glide.

which causes an applied force to be

ONE-TO-ONE VIBRATION-A

manifested 90° in the direction of

LATERIAL VIBRATION-A vibra-

low frequency vibration having one

rotation from the point where the

tion in which the movement is in a lat-

beat per revolution of the rotor. This

force is applied.

eral direction, such as imbalance of the

vibration can be either lateral, vertical,

main rotor.

or horizontal.

HUMAN FACTORS-The study of

how people interact with their

LEAD AND LAG-The fore (lead)

OUT OF GROUND EFFECT

environment. In the case of general

and aft (lag) movement of the rotor

(OGE) HOVER-Hovering greater

aviation, it is the study of how pilot

blade in the plane of rotation.

than one diameter distance above the

performance is influenced by such

surface. Because induced drag is

issues as the design of cockpits, the

LICENSED EMPTY WEIGHT-

greater while hovering out of ground

function of the organs of the body, the

Basic empty weight not including full

effect, it takes more power to achieve

effects of emotions, and the interac-

engine oil, just undrainable oil.

a hover out of ground effect.

G-3

PARASITE DRAG-The part of

ROTATIONAL VELOCITY-The

STANDARD ATMOSPHERE-A

total drag created by the form or shape

component of relative wind produced

hypothetical atmosphere based on

of helicopter parts.

by the rotation of the rotor blades.

averages in which the surface temper-

ature is 59°F (15°C), the surface pres-

PAYLOAD-The term used for pas-

sure is 29.92 in. Hg (1013.2 Mb) at

ROTOR-A complete system of

sengers, baggage, and cargo.

sea level, and the temperature lapse

rotating airfoils creating lift for a heli-

rate is approximately 3.5°F (2°C) per

copter or gyroplane.

1,000 feet.

PENDULAR ACTION-The lateral

or longitudinal oscillation of the fuse-

ROTOR DISC AREA-See disk

STATIC STOP-A device used to

lage due to it being suspended from

area.

limit the blade flap, or rotor flap, at

the rotor system.

low r.p.m. or when the rotor is

ROTOR BRAKE-A device used to

stopped.

PITCH ANGLE-The angle between

stop the rotor blades during shutdown.

the chord line of the rotor blade and

STEADY-STATE FLIGHT-A con-

the reference plane of the main rotor

ROTOR FORCE-The force pro-

dition when a rotorcraft is in straight-

hub or the rotor plane of rotation.

duced by the rotor in a gyroplane. It is

and-level, unaccelerated flight, and all

comprised of rotor lift and rotor drag.

forces are in balance.

PREROTATION-In a gyroplane, it

is the spinning of the rotor to a suffi-

SYMMETRICAL AIRFOIL-An

SEMIRIGID ROTOR-A rotor sys-

cient r.p.m. prior to flight.

airfoil having the same shape on the

tem in which the blades are fixed to the

top and bottom.

hub but are free to flap and feather.

PRESSURE ALTITUDE-The height

above the standard pressure level of

TAIL ROTOR-A rotor turning in a

SETTLING WITH POWER-See

29.92 in. Hg. It is obtained by setting

plane perpendicular to that of the main

vortex ring state.

29.92 in the barometric pressure win-

rotor and parallel to the longitudinal

dow and reading the altimeter.

axis of the fuselage. It is used to con-

SHAFT TURBINE-A turbine

trol the torque of the main rotor and to

engine used to drive an output shaft

provide movement about the yaw axis

PROFILE DRAG-Drag incurred

commonly used in helicopters.

of the helicopter.

from frictional or parasitic resistance

of the blades passing through the air. It

does not change significantly with the

SKID-A flight condition in which

TEETERING HINGE-A hinge

angle of attack of the airfoil section,

the rate of turn is too great for the

that permits the rotor blades of a semi-

but it increases moderately as airspeed

angle of bank.

rigid rotor system to flap as a unit.

increases.

THRUST-The force developed by

SKID SHOES-Plates attached to

the rotor blades acting parallel to the

RESULTANT RELATIVE WIND-

the bottom of skid landing gear pro-

relative wind and opposing the forces

Airflow from rotation that is modified

tecting the skid.

of drag and weight.

by induced flow.

SLIP-A flight condition in which

TIP-PATH PLANE-The imaginary

RETREATING BLADE-Any blade,

the rate of turn is too slow for the

circular plane outlined by the rotor

located in a semicircular part of the rotor

angle of bank.

blade tips as they make a cycle of

disc, where the blade direction is oppo-

rotation.

site to the direction of flight.

SOLIDITY RATIO-The ratio of

TORQUE-In helicopters with a sin-

the total rotor blade area to total rotor

RETREATING BLADE STALL-

gle, main rotor system, the tendency of

disc area.

A stall that begins at or near the tip of

the helicopter to turn in the opposite

a blade in a helicopter because of the

direction of the main rotor rotation.

high angles of attack required to com-

SPAN-The dimension of a rotor

pensate for dissymmetry of lift. In a

blade or airfoil from root to tip.

TRAILING EDGE-The rearmost

gyroplane the stall occurs at 20 to 40

edge of an airfoil.

percent outboard from the hub.

SPLIT NEEDLES-A term used to

describe the position of the two nee-

TRANSLATING TENDENCY-

RIGID ROTOR-A rotor system

dles on the engine/rotor tachometer

The tendency of the single-rotor heli-

permitting blades to feather but not

when the two needles are not superim-

copter to move laterally during hover-

flap or hunt.

posed.

ing flight. Also called tail rotor drift.

G-4

TRANSLATIONAL LIFT-The

UNDERSLUNG-A rotor hub that

VORTEX RING STATE-A tran-

additional lift obtained when entering

rotates below the top of the mast, as

sient condition of downward flight

forward flight, due to the increased

on semirigid rotor systems.

(descending through air after just pre-

efficiency of the rotor system.

viously being accelerated downward

UNLOADED ROTOR-The state of

by the rotor) during which an appre-

a rotor when rotor force has been

ciable portion of the main rotor sys-

T R A N S V E R S E - F L O W

removed, or when the rotor is operating

tem is being forced to operate at

EFFECT-A condition of increased

under a low or negative G condition.

angles of attack above maximum.

drag and decreased lift in the aft por-

Blade stall starts near the hub and pro-

tion of the rotor disc caused by the air

USEFUL LOAD-The difference

gresses outward as the rate of descent

having a greater induced velocity and

between the gross weight and the

increases.

angle in the aft portion of the disc.

basic empty weight. It includes the

flight crew, usable fuel, drainable oil,

WEIGHT-One of the four main

TRUE ALTITUDE-The actual

if applicable, and payload.

forces acting on a rotorcraft.

height of an object above mean sea

Equivalent to the actual weight of the

level.

VARIATION-The angular differ-

rotorcraft. It acts downward toward

ence between true north and magnetic

the center of the earth.

TURBOSHAFT ENGINE-A tur-

north; indicated on charts by isogonic

bine engine transmitting power

lines.

YAW-The movement of a rotorcraft

through a shaft as would be found in a

about its vertical axis.

turbine helicopter.

VERTICAL VIBRATION-A vibra-

tion in which the movement is up and

TWIST GRIP-The power control

down, or vertical, as in an out-of-track

on the end of the collective control.

condition.

G-5

INDEX

normal to a hover, 9-19

normal to the surface, 9-20

pinnacle, 10-8

ABORTED TAKEOFF, GYROPLANE 21-1

shallow approach, 10-5

ACCELERATE/STOP DISTANCE 21-1

steep, 10-4

AERODYNAMICS 2-1, 3-1, 16-1

ARM 7-4

autorotation, 3-8

ASYMMETRICAL AIRFOIL 2-1

forward flight, 3-5

ATTITUDE INDICATOR 12-3

general, 2-1

ATTITUDE INSTRUMENT FLYING 12-1

gyroplane, 16-1

AUTOKINESIS 13-3

helicopter, 3-1

AUTOPILOT 5-10

hovering flight, 3-1

AUTOROTATION 11-1

rearward flight, 3-8

aerodynamics, 3-8, 16-1

sideward flight, 3-8

during instrument flight, 12-19

turning flight, 3-8

from a hover, 11-4

vertical flight, 3-4, 16-1

power recovery, 11-3

AERONAUTICAL DECISION MAKING (ADM) 14-1, 22-1

straight-in, 11-2

decision-making process, 14-3

with turn, 11-3

definitions, 14-2

AXIS OF ROTATION 2-2

error chain, 14-1

factors affecting decision making, 14-5

hazardous attitudes, 14-6, 22-1

operational pitfalls, 14-8

origin, 14-2

pilot error, 14-1

BASIC EMPTY WEIGHT 7-1

risk management, 14-4

BERNOULLI’S PRINCIPLE 2-3

situational awareness, 14-8

BLADE

stress management, 14-6

coning, 3-2

use of resources, 14-6

driven region, 3-9, 16-2

workload management, 14-7

driving region, 3-9, 16-2

AGONIC LINE 12-5

feather, 1-1

AIRCRAFT LIGHTING 13-3

flap, 1-1, 16-6, 20-1

AIRFOIL 2-1

lead/lag, 1-1

angle of attack, 2-2

reverse flow, 16-3

camber, 2-2

stall, 11-10

center of pressure, 2-1

stall region, 3-9, 16-2

chord line, 2-2

BLOWBACK 3-8

leading edge, 2-2

BUNTOVER 21-3

pitch angle, 2-2

relative wind, 2-2

resultant relative wind, 3-6

rotational relative wind, 3-6

span, 2-1

CARBURETOR 5-7

trailing edge, 2-2

heat, 5-8

twist, 2-1

ice, 5-7

AIRSPEED INDICATOR 12-1, 18-4

CENTER OF GRAVITY 7-2

AIR TAXI 9-9

aft CG, 7-2

AIRWORTHINESS DIRECTIVE 6-4

forward CG, 7-2

ALTIMETER 12-2, 18-4

lateral, 7-3, 7-7

ANGLE OF ATTACK 2-2

CENTER OF PRESSURE 2-1, 16-5

ANTI-ICING SYSTEMS 5-11

CENTRIFUGAL FORCE 3-2, 3-8

ANTITORQUE PEDALS 4-3

CENTRIPETAL FORCE 3-8

ANTITORQUE SYSTEM FAILURE 11-11

CLUTCH

ANTITORQUE SYSTEMS 1-2

belt drive, 5-4

tail rotor, 1-2

centrifugal, 5-4

fenestron, 1-2

freewheeling unit, 5-4

NOTAR®, 1-2

sprag, 5-4

APPROACHES

COANDA EFFECT 1-3

confined area, 10-7

COCKPIT MANAGEMENT 20-1

crosswind, 9-20

COLLECTIVE CONTROL, GYROPLANE 17-2

night, 13-5

COLLECTIVE PITCH CONTROL 4-1

I-1

COLLECTIVE PITCH/THROTTLE COORDINATION 4-2

turbine, 5-1

COMPASS CORRECTION CARD 12-5

ENGINE INSTRUMENTS 18-3

COMPASS DEVIATION 12-5

ENGINE STARTING PROCEDURE 9-2, 20-1

COMPASS ERRORS 12-4

ENVIRONMENTAL SYSTEMS 5-10

COMPASS TURNS 12-17

EYE 13-1

CONFINED AREA OPERATIONS

cones, 13-1

approach, 10-7

rods, 13-2

takeoff, 10-8

CONING 3-2

CONING ANGLE 18-1

CORIOLIS EFFECT 3-2

CORRELATOR/GOVERNOR 4-2

FALSE HORIZON 13-3

CREW RESOURCE MANAGEMENT 14-2

FENESTRON TAIL ROTOR 1-2

CYCLIC CONTROL, GYROPLANE 17-1

FLIGHT AT SLOW AIRSPEEDS 20-12

CYCLIC PITCH CONTROL 4-2

FLIGHT CONTROLS 1-3, 4-1

antitorque pedals, 4-3

collective pitch, 4-1, 17-2

cyclic pitch, 4-2, 17-1

rudder, 17-2

DATUM 7-3

swash plate assembly, 5-5

DECISION-MAKING PROCESS 14-3

throttle, 4-1, 17-1

DENSITY ALTITUDE 8-1, 20-5

FLIGHT DIVERSION 11-15

DIRECT CONTROL 15-2

FLIGHT INSTRUMENTS 12-1

DISC LOADING 2-4

airspeed indicator, 12-1, 18-4

DISSYMMETRY OF LIFT 3-6, 16-3, 20-1

altimeter, 12-2, 18-4

DIVERSION 11-15

attitude indicator, 12-3

DRAG 2-5

heading indicator, 12-3

form, 2-5

magnetic compass, 12-4

induced, 2-5

turn-indicators, 12-4

parasite, 2-6

vertical speed indicator, 12-2

profile, 2-5

FLIGHT MANUAL (See rotorcraft flight manual)

rotor, 16-4

FORCES IN A TURN 3-8

skin friction, 2-5

FOUR FORCES

total, 2-6

drag, 2-5, 16-4

DUAL ROTOR SYSTEM 1-1

lift, 2-3, 16-4

DYNAMIC ROLLOVER 11-7

thrust, 2-5, 16-4

weight, 2-4

FREEWHEELING UNIT 5-4

FUEL INJECTION 5-8

FUEL SYSTEMS 5-6

FULLY ARTICULATED ROTOR 1-1, 5-4, 18-1

EFFECTIVE TRANSLATIONAL LIFT 3-5

ELECTRICAL SYSTEMS 5-8

EMERGENCIES

aborted takeoff, 21-1

approach and landing, 21-3

autorotation, 11-1

GO-AROUND 9-20, 20-15

buntover, 21-3

GOVERNOR 4-2

dynamic rollover, 11-7

failure, 11-14

ground resonance, 11-7, 21-3

GROSS WEIGHT 7-1

instrument flight, 12-18

GROUND EFFECT 3-3

lift-off at low airspeeds and high angles of attack, 21-1

GROUND HANDLING 18-4

lost procedures, 11-16

GROUND REFERENCE MANEUVERS 9-14, 20-8

low G conditions, 11-10

rectangular course, 9-14, 20-8

low rotor r.p.m. and blade stall, 11-10

s-turns, 9-16, 20-10

mast bumping, 11-10

turns around a point, 9-17, 20-11

pilot-induced oscillation, 21-2

GROUND RESONANCE 11-7, 21-3

power pushover, 21-3

GYROPLANE

retreating blade stall, 11-6

components, 15-2

settling with power, 11-5

instruments, 18-3

systems malfunction, 11-11

stability, 16-5

vortex ring state, 11-5

types, 15-1

EMERGENCY EQUIPMENTAND SURVIVAL GEAR 11-16, 21-4

GYROSCOPIC INSTRUMENTS 12-3

ENGINE

attitude indicator, 12-3

reciprocating, 5-1, 18-1

heading indicator, 12-3

I-2

turn indicators, 12-4

unusual attitudes, 12-18

GYROSCOPIC PRECESSION 3-4

INSTRUMENT INTERPRETATION 12-6

INSTRUMENT TURNS 12-15

30° bank turn, 12-17

climbing and descending turns, 12-17

compass turns, 12-17

timed turns, 12-16

HANG TEST 19-4

turns to a predetermined heading, 12-16

HAZARDOUS ATTITUDES 14-5

ISOGONIC LINES 12-5

anti-authority, 14-6, 22-3

impulsivity, 14-6, 22-1

invulnerability, 14-6, 22-1

macho, 14-6, 22-2

resignation, 14-6, 22-2

HEADING INDICATOR 12-3

LANDING

HEIGHT/VELOCITY DIAGRAM 11-4, 19-3

crosswind, 9-11, 20-14

HELICOPTER SYSTEMS 5-1

high-altitude, 20-14

anti-icing, 5-11

illusions, 13-4

autopilot, 5-10

night, 13-5

carburetor, 5-7

normal, 20-13

clutch, 5-4

running/roll-on, 10-5

electrical, 5-8

short-field, 20-13

engine, 5-1

slope, 10-6

environmental, 5-10

soft-field, 20-14

flight control, 4-1

LANDING GEAR 1-2, 15-3, 18-4

fuel, 5-6

LAW OF CONSERVATION OF ANGULAR MOMENTUM 3-2

hydraulics, 5-9

L/D_MAX 2-6

main rotor, 5-4

LIFT 2-3, 16-4

pitot-static, 12-1

Bernoulli’s Principle, 2-3

stability augmentation system, 5-10

magnus effect, 2-3

swash plate assembly, 5-5

Newton’s Third Law of Motion, 2-4

tail rotor drive, 5-3

LIFT-OFF AT LOW AIRSPEED AND HIGH ANGLE OF

transmission, 5-3

ATTACK 21-1

HIGH RATE OF DESCENT 20-12

LIFT-TO-DRAG RATIO 2-6

HINGES 5-5

LOAD FACTOR 2-4

HOVERING

LOSS OF TAIL ROTOR EFFECTIVENESS 11-12

aerodynamics, 3-1

LOST PROCEDURES 11-16

flight, 9-5

LOW G CONDITIONS 11-10

HOVERING OPERATIONS

LOW ROTOR RPM 11-10

autorotation, 11-4

LTE (See loss of tail rotor effectiveness)

forward flight, 9-7

rearward flight, 9-8

sideward flight, 9-7

turn, 9-6

vertical takeoff, 9-5

HOVER TAXI 9-9

MAGNETIC COMPASS 12-4

HUMAN FACTORS 14-1

acceleration/deceleration error, 12-5

HYDRAULIC FAILURE 11-14

compass correction card, 12-5

magnetic deviation, 12-5

magnetic dip, 12-5

turning error, 12-5

variation, 12-4

INDUCED DRAG 2-5

MAGNUS EFFECT 2-3

INDUCED FLOW 3-6

MAIN ROTOR SYSTEM 1-1, 5-4

INSTRUMENT CROSS-CHECK 12-5

combination, 5-5

INSTRUMENT FLIGHT 12-5

fully articulated, 1-1, 5-4

aircraft control, 12-7

rigid, 1-2, 5-5

bank control, 12-9

semirigid, 1-2, 5-5

emergencies, 12-18

MANEUVERS 9-1, 10-1, 20-1

straight-and-level flight, 12-7

after landing and securing, 9-20, 20-15

straight climbs, 12-11

approaches, 9-19

straight descents, 12-14

climb, 9-13, 20-6

takeoff, 12-19

confined area operations, 10-7

turns, 12-15

crosswind landing, 9-20, 20-14

I-3

crosswind takeoff, 9-11, 20-4

NIGHT VISION 13-2

descent, 9-14, 20-6

NOISE ABATEMENT PROCEDURES 9-20

engine start, 9-2, 20-1

NO TAIL ROTOR 1-2

flight at slow airspeeds, 20-12

go-around, 9-20, 20-15

ground reference maneuvers, 9-14, 20-8

high-altitude landing, 20-14

high-altitude takeoff, 20-4

high rate of descent, 20-12

hovering, 9-5

OPERATIONAL PITFALLS 14-8

jump takeoff, 20-5

maximum performance takeoff, 10-2

normal landing, 20-13

normal takeoff, 20-3

pinnacle operations, 10-8

preflight, 9-1, 20-1

PARASITE DRAG 2-6

prerotation, 20-2

PAYLOAD 1-1, 7-1

quick stop, 10-3

PENDULAR ACTION 3-2, 16-5

rapid deceleration, 10-3

PERFORMANCE CHARTS 8-3, 19-2

ridgeline operations, 10-8

climb, 8-5

rotor engagement, 9-2

hovering, 8-3

running/rolling landing, 10-5

takeoff, 8-5

running/rolling takeoff, 10-2

PERFORMANCE FACTORS 8-1

shallow approach, 10-5

altitude, 8-2

short-field landing, 20-13

atmospheric pressure, 8-1

short-field takeoff, 20-4

density altitude, 8-1

slope operations, 10-6

humidity, 8-2

soft-field landing, 20-14

temperature, 8-2

soft-field takeoff, 20-5

weight, 8-2

steep approach, 10-4

winds, 8-2

straight-and-level flight, 9-12, 20-6

PILOT ERROR 14-1

takeoff from a hover, 9-10

PILOT-INDUCED OSCILLATION (PIO) 21-2

takeoff from the surface, 9-11

PINNACLE OPERATIONS

taxiing, 9-8, 20-1

approach, 10-8

traffic patterns, 9-18

landing, 10-8

turns, 9-12, 20-7

takeoff, 10-9

vertical takeoff, 9-5

PITCH, AIRCRAFT 2-2

MAST BUMPING 11-10

PITCH HORN 5-4

MAXIMUM GROSS WEIGHT 7-1

PITOT-STATIC INSTRUMENTS 12-1

MAXIMUM PERFORMANCE TAKEOFF 10-2

airspeed indicator, 12-1, 18-4

MEL (See minimum equipment list)

altimeter, 12-2, 18-4

MINIMUM EQUIPMENT LIST 9-1

errors, 12-2

MOMENT 7-4

vertical speed indicator (VSI), 12-2

PLACARDS 6-3

POH (See rotorcraft flight manual)

POWERPLANT 1-3, 15-2

POWER PUSHOVER 21-3

PREFLIGHT INSPECTION 9-1, 20-1

NEVER EXCEED SPEED (V_NE) 3-7, 6-2

night, 13-4

NEWTON’S THIRD LAW OF MOTION 2-4

PREROTATE 15-2, 18-2, 20-2

NIGHT APPROACH 13-5

PREROTATOR 18-2

NIGHT FLIGHT 13-4

electrical, 18-3

approach, 13-5

hydraulic, 18-2

collision avoidance, 13-5

mechanical, 18-2

engine starting and rotor engagement, 13-4

tip jets, 18-3

en route procedures, 13-5

PRESSURE ALTITUDE, 8-1

landing, 13-5

PROFILE DRAG 2-5

preflight, 13-4

PROPELLER THRUST LINE 16-5

takeoff, 13-4

taxi technique, 13-4

NIGHT MYOPIA 13-3

NIGHT OPERATIONS 13-1

NIGHT PHYSIOLOGY 13-1

NIGHT SCANNING 13-2

QUICK STOP 10-3

I-4

horizontal stabilizer, 16-5

pitch inertia, 16-5

propeller thrust line, 16-5

RAPID DECELERATION 10-3

rotor force, 16-6

RECIPROCATING ENGINE 5-1

trimmed condition, 16-6

RECONNAISSANCE PROCEDURES

STANDARD ATMOSPHERE 8-1

ground, 10-1

STANDARD-RATE TURN 12-4

high, 10-1

STARTING PROCEDURE 9-2

low, 10-1

STATIC STOPS 5-5

RECTANGULAR COURSE 9-14, 20-8

STEADY-STATE FLIGHT 2-4

REFERENCE DATUM 7-3

STEEP TURNS 20-8

RELATIVE WIND 2-2

STRESS MANAGEMENT 14-6

RESULTANT RELATIVE WIND 3-6

S-TURNS 9-16, 20-10

RETREATING BLADE STALL 11-6, 16-3

SWASH PLATE ASSEMBLY 5-5

REVERSE FLOW 16-3

SYMMETRICAL AIRFOIL 2-1

RIGID ROTOR 1-2, 5-5

SYSTEM MALFUNCTIONS 11-11

RISK ELEMENTS 14-4

antitorque, 11-11

RISK MANAGEMENT 14-4

governor, 11-14

ROLL, AIRCRAFT 2-2

hydraulic, 11-14

ROTATIONAL RELATIVE WIND 3-6

main drive shaft, 11-14

ROTORCRAFT FLIGHT MANUAL 6-1, 19-1

aircraft systems and description, 6-4

emergency procedures, 6-3, 19-3

general information, 6-1

gyroplane, 19-1

handling, servicing, and maintenance, 6-4

TACHOMETER 5-3, 18-3

helicopter, 6-1

TAIL ROTOR 1-2, 5-3

normal procedures, 6-3

TAIL ROTOR FAILURE 11-11

operating limitations, 6-1

TAIL SURFACES 15-2

performance, 6-3, 19-2

TAKEOFF

safety and operational tips, 6-4

confined area, 10-8

supplements, 6-4

crosswind, 9-11, 20-4

weight and balance, 6-4, 19-1

from a hover, 9-10

ROTOR DRAG 16-4

from the surface, 9-11

ROTOR ENGAGEMENT 9-2

high altitude, 20-4

ROTOR FORCE 16-3

jump, 20-5

ROTOR LIFT 16-4

maximum performance, 10-2

ROTOR SAFETY 9-2

night, 13-4

ROTOR SYSTEMS 5-4, 18-1

normal, 20-3

combination, 5-5

pinnacle, 10-9

fully articulated, 1-2, 5-4, 18-1

running/rolling, 10-2

semirigid, 1-2, 5-5, 18-1

short-field, 20-4

rigid, 1-2, 5-5

slope, 10-6

RUDDER 17-2

soft-field, 20-5

to a hover, 9-5

TAXIING 9-8, 20-1

air, 9-9

hover, 9-9

night, 13-4

SAFETY CONSIDERATIONS 9-2

surface, 9-9

SEMIRIGID ROTOR SYSTEM 1-2, 5-5, 18-1

TEETER BOLT 18-1

SETTLING WITH POWER 11-5

TEETERING HINGE 5-5

SITUATIONAL AWARENESS 14-8

THROTTLE 4-1, 17-1

SKID 9-13, 20-7

THRUST 2-5, 16-4

SKIN FRICTION DRAG 2-5

TIP JETS 18-3

SLIP 9-13, 20-7

TIP-PATH PLANE 2-2, 9-5

SLIP/SKID INDICATOR 12-4, 18-4

TIP SPEED 3-7, 16-1

SLOPE OPERATIONS

TORQUE 1-1, 3-1

landing, 10-6

TOTAL DRAG 2-6

takeoff, 10-6

TOWER BLOCK 18-1

STABILITY AUGMENTATION SYSTEM (SAS) 5-10

TOWER PLATE 18-1

STABILITY, GYROPLANE 16-5

TRAFFIC PATTERNS 9-18

center of pressure, 16-5

TRANSLATING TENDENCY 3-1

fuselage drag, 16-5

TRANSLATIONAL LIFT 3-5

I-5

ROTORCRAFT FLYING HANDBOOK (2000) - page 3