Robinson Helicopter Company RTR 660 (Number R00015LA). Maintenance Manual (2012)

18-41 Collective Travel

NOTE

Lengthening pitch links increases blade angles.

NOTE

When making adjustments, keep pitch links as close to neutral

(mid-travel) position as possible to preserve the adjustment

range for flight checks.

A. Collective Down

Refer to Figure 18-8. Position collective stick full up and apply friction. Place

MT759-1 rigging blocks around cyclic stick in cyclic box assembly. Verify top of ball

is flush with tube within 0.030 inch. Adjust all swashplate push-pull tubes exactly

the same amount as required (one full turn = 0.48°).

Position collective stick full down and apply friction.

Rotate blades so pitch links are aligned with helicopter longitudinal axis.

Measure and record blade angles per Section 18-40 Part B to determine the values

below. Rotate blades 180° and align per step 3 as required.

BLUE BLADE

RED BLADE

Pitch horn forward

Pitch horn aft

÷ 2 =

Blade angles must average between 1.0° and 2.0° for collective down position.

(Final blade angle for collective down position is determined during autorotation rpm

adjustment.) Adjust main rotor blade pitch links per Section 18-13 as required (one

full barrel turn = 0.72°) until blade angles, when blades are positioned pitch horn

forward, are within 0.2°. Adjust pitch links until blade angles, when blades are

positioned pitch horn aft, are also within 0.2°.

NOTE

After making adjustments, position collective stick full up and

apply friction. Verify top of swashplate ball is flush with tube

within 0.030 inch per Figure 18-8. Adjust all swashplate push-

pull tubes exactly the same amount as required (one full turn =

0.48°). Lengthening all push-pull tubes increases blade angles.

Page 18.24

Chapter 18 Track and Balance

18-41 Collective Travel

B . Collective Up

Position collective stick full up and apply friction. Place MT759-1 rigging blocks

around cyclic stick in cyclic box assembly.

Rotate blades so pitch links are aligned with helicopter longitudinal axis.

Measure and record blade angles per Section 18-40 Part B to determine the values

below. Rotate blades 180° and align per step 2 as required.

BLUE BLADE

RED BLADE

Pitch horn forward

Pitch horn aft

÷ 2 =

For collective up position, blade angles must average between 12.5° and 13.5°

more than collective down position average. Adjust main rotor blade pitch links per

Section 18-13 as required (one full barrel turn = 0.72°) until blade angles, when

blades are positioned pitch horn forward, are within 0.2°. Adjust pitch links until

blade angles, when blades are positioned pitch horn aft, are also within 0.2°.

NOTE

Remeasure collective down blade angles after making adjustment

for collective up blade angles.

NOTE

After making adjustments, position collective stick full up and

apply friction. Verify top of swashplate ball is flush with tube

within 0.030 inch per Figure 18-8. Adjust all swashplate push-

pull tubes exactly the same amount as required (one full turn =

0.48°). Lengthening all push-pull tubes increases blade angles.

Chapter 18 Track and Balance

Page 18.25

18-42 Cyclic Travel

A. Cyclic Left

1. Position collective stick full down. Position cyclic stick in the longitudinal neutral

(mid travel) position, and against left stop. Apply control frictions; sandbag cyclic

stick as required.

2. Rotate blades so pitch links are aligned with helicopter lateral axis.

3. Measure and record blade angles per Section 18-40 Part B to determine the values

below. Rotate blades 180° and align per step 2 as required.

BLUE BLADE

RED BLADE

Pitch horn right

Pitch horn left

÷ 2 =

4. Blade angles must average between 7.5° and 8.5° for cyclic left position. Adjust

swashplate forward left or right push-pull tube as required (one full turn = 0.6°).

Cyclic Right

Position collective stick full down. Position cyclic stick in the longitudinal neutral

(mid travel) position, and against right stop. Apply control frictions; sandbag cyclic

stick as required.

Rotate blades so pitch links are aligned with helicopter lateral axis.

Measure and record blade angles per Section 18-40 Part B to determine the values

below. Rotate blades 180° and align per step 2 as required.

BLUE BLADE

RED BLADE

Pitch horn right

Pitch horn left

÷ 2 =

Blade angles must average between 6.0° and 7.0° for cyclic right position. Adjust

swashplate forward left or right push-pull tube as required (one full turn = 0.6°).

NOTE

Remeasure cyclic left blade angles after making adjustment for

cyclic right blade angles.

Page 18.26

Chapter 18 Track and Balance

18-42 Cyclic Travel (continued)

C. Cyclic Forward

1. Position collective stick full down. Position cyclic stick in the lateral neutral (5 inches

to left of right stop) position, and against forward stop. Apply control frictions;

sandbag cyclic stick as required.

2. Rotate blades so pitch links are aligned with helicopter longitudinal axis.

3. Measure and record blade angles per Section 18-40 Part B to determine the values

below. Rotate blades 180° and align per step 2 as required.

BLUE BLADE

RED BLADE

Pitch horn forward

Pitch horn aft

÷ 2 =

4. Blade angles must average between 13.50° and 14.25° for cyclic forward position.

Adjust swashplate aft push-pull tube as required (one full turn = 0.44°). A coarse

adjustment can be made by adjusting swashplate forward push-pull tubes exactly

the same amount (one full turn = 0.6°).

D. Cyclic Aft

Position collective stick full down. Position cyclic stick in the lateral neutral (5 inches

to left of right stop) position, and against aft stop. Apply control frictions; sandbag

cyclic stick as required.

Rotate blades so pitch links are aligned with helicopter longitudinal axis.

Measure and record blade angles per Section 18-40 Part B to determine the values

below. Rotate blades 180° and align per step 2 as required.

BLUE BLADE

RED BLADE

Pitch horn forward

Pitch horn aft

÷ 2 =

Blade angles must average between 13.50° and 14.25° for cyclic aft position.

Adjust swashplate aft push-pull tube as required (one full turn = 0.44°). A coarse

adjustment can be made by adjusting swashplate forward push-pull tubes exactly

the same amount (one full turn = 0.6°).

NOTE

Remeasure cyclic forward blade angles after making adjustment

for cyclic aft blade angles.

Chapter 18 Track and Balance

Page 18.27

18-50 Tail Rotor Flight Control Rigging

18-51 Pedals

1. Insert a 3/16-inch diameter rigging pin through the hole in the right-hand keel panel and

the rigging pin holes in the C317-7 bellcrank.

2. Adjust the F121-9 push-pull tubes as required to obtain a dimension of 5.24 ± 0.03

in. from the lower forward NAS6604-9 bolt in C317-5 bellcrank and horizontal pedal

torque tube.

18-52 Forward Bellcrank

Remove the rigging pin and place the left pedal against its stop. Adjust the F121-11 push-

pull tube to obtain 1.08 - 1.18 inches between the bellcrank and bulkhead.

18-53 Intermediate Bellcrank

With left pedal at stop, adjust the C121-17 push-pull tube length as required to obtain 0.35

± 0.03 inch between two faces of pitch control assembly and the housing.

FIGURE 18-11 TAIL ROTOR BLADE RIGGING

Page 18.28

Chapter 18 Track and Balance

18-60 Tail Rotor Blade Rigging

Level helicopter laterally, and longitudinally via main rotor hub, per Section 8-12.

Place left (or right) pedal against its stop. Position tail rotor blades parallel to the

tailcone.

Refer to Figure 18-11. Tape a tracking stick to tailcone at blade tip. A tracking stick can

be made using a 1” x 12” strip of aluminum with a 90º bend 2 inches from one end.

Rotate tail rotor shaft weldment and mark tracking stick where each blade tip drain hole

passes. Adjust (teeter) tail rotor hub on output shaft until both blade tips pass the same

point on the tracking stick.

Using felt tip marker, mark inboard surface of both tail rotor blades 7.25 inches from

each blade tip. Lay 1-inch wide strip of masking tape chordwise on each blade, centered

over marking. Mark each blade with a different color designation, such as red or blue.

Have a second person hold one blade tip at the left pedal track mark with the left pedal

against its stop. Position MT525-2 rigging fixture on the aft blade, against the inboard

surface. Position propeller protractor against the fixture, measure the blade angle, and

record data below. Rotate the tail rotor 180,° and record the opposite blade angle.

Pedals Full Left

Blue Blade

Red Blade

÷ 2 =

° (18.5/19.0° required)

Difference between blue and red blade angles may not exceed 0.4°. If blade angles

exceed this limit, remove tail rotor assembly per Section 64-10, rotate assembly one-

half revolution, and install assembly per Section 64-10. Repeat previous steps. If blade

angles still exceed relative limit, contact RHC Technical Support for replacement blade

assistance.

Adjust C121-17 push-pull tube rod ends per Section 5-33 and Figures 5-1 & 5-2 as

required to obtain blade angle between 18.5° and 19.0°. One full turn of the rod end

will change the blade angle 0.33°.

Have a second person hold one blade tip at the right pedal track park with the right pedal

against its stop. Position MT525-2 rigging fixture on the aft blade, against the inboard

surface. Position propeller protractor against the fixture, measure the blade angle, and

record data below. Rotate the tail rotor 180,° and record the opposite blade angle.

Pedals Full Right

Blue Blade

Red Blade

÷ 2 =

° (15.5/16.5° required)

10.

Adjust C121-17 push-pull tube rod ends per Section 5-33 and Figures 5-1 & 5-2 as

required to obtain blade angle between 15.5° and 16.5°. If adjusted, recheck left pedal

blade angles per previous steps.

Chapter 18 Track and Balance

Page 18.29

18-60 Tail Rotor Blade Rigging (continued)

11. If the blade angle range for left and right pedal settings cannot be obtained using the

preceding steps, the pedal travel is either too great or too small. Use the following

procedure to check and adjust pedal travel:

a. Add right and left pedal blade angles together. If the total is less than 34.0°, the pedal

total travel is too small. If the total is greater than 35.5°, the total travel is too great.

b. If the total travel is too small, first increase the right pedal travel by increasing the

length of C121-9 push-pull tube. To increase the left pedal travel, decrease the length

of C343-3 or -9 push-pull tube.

c. To decrease the total travel, shorten the C121-9 push-pull tube for right pedal travel

and increase the length of C343-3 or -9 push-pull tube for left pedal travel.

d. Recheck left and right pedal blade angles per previous steps.

12. Balance tail rotor per Section 18-20.

Page 18.30

Chapter 18 Track and Balance

CHAPTER 20

STANDARD PRACTICES

Section

Title

Page

20-10

Cleaning

20.1

20-20

Lubrication

20.2

20-30

Torque Requirements

20.3

20-31

Torque Seal

20.5

20-32

Standard Torques

20.6

20-33

Special Torques

20.7

20-34

Push-Pull Tube Rod End Adjustment

20.11

20-40

Non-Destructive Testing

20.12

20-41

Magnetic Particle Inspection

20.12

20-42

Fluorescent Penetrant Inspection

20.13

20-50

Corrosion Control

20.13

20-60

Priming and Painting

20.13

20-70

Approved Materials

20.16

20-71

Paint Strippers

20.16

20-72

Solvents and Cleaners

20.16

20-73

Fillers and Putty

20.17

20-74

Torque Seal

20.17

20-75

Primers

20.17

20-76

Powder Coat

20.18

20-77

Paints

20.19

20-78

Lubricants

20.22

20-79

Adhesives and Sealants

20.23

20-80

Storage Limits

20.24

20-90

Miscellaneous Practices

20.25

20-91

Part Interchangeability

20.25

20-92

Thermal Fitting Parts

20.26

20-93

Replacement Component Identification (Data) Plates . . .

20.26

25 OCT 2010

Chapter 20 Standard Practices

Page 20.i

CHAPTER 20

STANDARD PRACTICES

20-10 Cleaning

NOTE

Remove turbine exhaust stains from engine cowling, tailcone,

empennage, and tail rotor blades after every flight to prevent

permanent discoloration.

CAUTION

Wash helicopter exterior surfaces, windshields, and windows

with mild soap and water. Harsh abrasives, alkaline soaps, or

detergents can scratch painted or plastic surfaces, or cause

corrosion of metal. Protect areas where cleaning solution could

cause damage.

CAUTION

Never use high-pressure spray to clean helicopter. Never blow

compressed air into main or tail rotor blade tip drain holes, pitot

tube, or static ports.

WARNING

Refer to appropriate Material Safety Data Sheet (MSDS) and

take necessary safety precautions when working in proximity to

hazardous materials.

A. Cleaning Exterior Surfaces

1. Rinse away loose dirt and debris from exterior surface with clean water.

2. Apply mild soap and clean warm water solution to exterior surface using a clean,

soft cloth, sponge, or soft bristle brush. Use caution near antennas and sensitive

equipment.

3. Remove oil and grease using a cloth wetted with aliphatic naphtha.

4. Rinse all surfaces thoroughly.

5. If desired, polish painted surfaces with a good quality automotive wax using soft cleaning

cloths, or a chamois cloth, free of abrasive debris.

25 OCT 2010

Chapter 20 Standard Practices

Page 20.1

20-10 Cleaning (continued)

Cleaning Windshield and Windows

CAUTION

Do not use gasoline, other alcohols, benzene, carbon tetrachloride,

thinner, acetone, or window (glass) cleaning sprays.

1. Rinse away loose dirt and debris from windshield and windows with clean water.

2. Apply mild soap and clean warm water solution, or aircraft plastic cleaner, to windshield

and windows using a clean, soft cloth or sponge in a straight back and forth motion. Do

not rub harshly.

3. Remove oil and grease using a cloth wetted with isopropyl alcohol (rubbing alcohol) or

aliphatic naphtha.

4. After cleaning plastic surfaces, apply a thin coat of hard polishing wax. Rub lightly with

a soft cloth. Do not use a circular motion.

5. To remove scratches, rub windshield or windows with jeweler’s rouge then hand polish

with commercial plastic polish. Polish in figure eight motion.

C. Cleaning Seat Assemblies and Back Rests

1. Vacuum and brush, then wipe with damp cloth. Dry immediately.

2. Soiled upholstery, except leather, may be cleaned with a good upholstery cleaner suitable

for the material. Follow manufacturer’s instructions. Avoid soaking or harsh rubbing.

3. Leather should be cleaned with saddle soap or a mild hard soap and water.

D. Cleaning Carpet

Remove loose dirt with a whisk broom or vacuum. For soiled spots and stains, use

nonflammable dry cleaning liquid.

20-20 Lubrication

WARNING

Refer to appropriate Material Safety Data Sheet (MSDS) and

take necessary safety precautions when working in proximity to

hazardous materials.

All R66 bearings are sealed or self-lubricating and do not require periodic lubrication.

The engine oil tank, the main and tail rotor gearboxes, and the hydraulic reservoir require

servicing when indicated by sight gage level. Additionally, change engine, gearbox, or hydraulic

oil and clean respective sight gage when oil becomes so dirty its level cannot be determined.

Change hydraulic oil when notedly odorous.

When installing a new or overhauled main rotor gearbox, replace filter at first 100-hour

inspection after installation. Thereafter, replace filter at scheduled intervals per Section 5-20.

When installing a new or overhauled tail rotor gearbox, drain and flush after first 4 hours

of flight or first chip light, whichever occurs first. Thereafter, drain and flush gearbox at

scheduled intervals per Section 5-20.

Servicing procedures are located in Chapter 12.

Page 20.2

Chapter 20 Standard Practices

25 OCT 2010

20-30 Torque Requirements

A. Tool Calibration

Dimensions and tolerances given in this manual are critical. Calibrate measuring tools per

manufacturers recommendation at least once a year, when tool is dropped, misused, or

calibration is suspect. This includes torque wrenches, micrometers, calipers, dial indicators,

and spring scales.

WARNING

Proper torque is critical. Always use calibrated wrenches and

undamaged, properly lubricated

(where applicable) hardware.

Ensure clamping surfaces are clean, and clamp only bare metal

or wet-primed surfaces. Improper torque or dirty or painted

clamping surfaces may result in loss of clamp-up, hardware or

part damage, and premature failure.

B. Torque Value

Torque fasteners to standard dry values listed in Section 20-32 unless otherwise specified.

If torque is applied by rotating bolt, increase torque value by 10% to account for higher

friction at bolthead and shank.

For example, the torque wrench setting for an NAS1305 bolt used with a NAS1068 nutplate

is determined as follows:

NAS1305 bolt (5 indicates 5/16 inch size) dry torque per Section 20-32

240 in.-lb

Add 10% because torque must be applied at bolt head

+ 24 in.-lb

Torque wrench setting

264 in.-lb

C. Secondary Locking Mechanism

A secondary locking mechanism is required on all critical fasteners. B330 stamped nuts

(palnuts) serve as secondary locking mechanisms in most areas on the helicopter, and are

torqued per Section 20-32. The R66 Illustrated Parts Catalog (IPC) lists secondary locking

mechanisms for specific fasteners.

D. Critical Fastener

A critical fastener is one which, if removed or lost, would jeopardize safe operation of the

helicopter. This includes joints in the primary control system, and non-fail-safe structural

joints in the airframe, landing gear, and drive system.

WARNING

Assembly of flight controls is critical and requires inspection

by a qualified person. If a second person is not available,

RHC recommends the installer take a 5-minute break prior to

inspecting flight control connections he has assembled.

25 OCT 2010

Chapter 20 Standard Practices

Page 20.3

Given

Symbols

= Unknown

= Torque wrench setting

= 135 in.-lb

= Torque applied to fastener

= 10 in.

= Length of torque wrench

= 1.5 in.

= Length of adapter

When using an adapter that lengthens torque wrench effective length,

calculate torque wrench setting using the formula below:

EXAMPLE

T x L

135 x 10

1350

Solve for Y =

= 117.39

L + A

10 + 1.5

11.5

Set torque wrench to 117 in.-lb to torque fastener to 135 in.-lb.

FIGURE 20-1 LENGTHENING TORQUE WRENCH EFFECTIVE LENGTH

Given

Symbols

= Unknown

= Torque wrench setting

= 135 in.-lb

= Torque applied to fastener

= 10 in.

= Length of torque wrench

= 1.5 in.

= Length of adapter

When using an adapter that shortens the torque wrench effective length,

calculate torque wrench setting using the formula below:

EXAMPLE

T x L

135 x 10

1350

Solve for Y =

= 158.82

L - A

10 - 1.5

8.5

Set torque wrench to 159 in.-lb to torque fastener to 135 in.-lb.

FIGURE 20-2 SHORTENING TORQUE WRENCH EFFECTIVE LENGTH

Page 20.4

Chapter 20 Standard Practices

25 OCT 2010

20-30 Torque Requirements (continued)

WARNING

Two threads minimum must be exposed beyond nut on any

installation to insure proper locking of fastener. Four threads

maximum may be exposed. More than four threads exposed

may allow nut to seat against bolt shank, resulting in insufficient

joint clamping.

CAUTION

Never substitute AN bolts for NAS bolts. NAS bolts have higher

tensile strength.

Torque Requirements

1. Bolt and nut are to be clean and dry except when assembly procedure specifies anti-

seize or thread-locking compound.

2. If chattering or jerking occurs, disassemble and re-torque fastener.

3. If special adapters which change effective length of torque wrench are used, final torque

value must be calculated using formulas in Figures 20-1 and 20-2.

4. Proper thread engagement requires 2-4 threads beyond primary self-locking nut (palnuts

excepted).

5. Torque wrenches must be calibrated annually, when dropped, or when a calibration

error is suspected.

Any self-locking nut whose drag has deteriorated appreciably must be replaced. Damaged

hardware must be replaced.

20-31 Torque Seal

WARNING

Refer to appropriate Material Safety Data Sheet (MSDS) and

take necessary safety precautions when working in proximity to

hazardous materials.

Refer to Figure 5-1. Torque seal (paint) is applied to all critical fasteners after palnut

installation in a stripe extending from the fastener's exposed threads across both nuts

and onto the component. Subsequent rotation of the nut or bolt can be detected visually.

Position torque stripes for maximum visibility during preflight inspections. Approved torque

seal is listed in Section 20-74.

Chapter 20 Standard Practices

Page 20.5

20-32 Standard Torques

EXAMPLE

DRY TORQUE

FASTENER SERIES

SIZE

FASTENER

(IN.-LB)

10-32

NAS6603

NAS 1300 Bolts

1/4-28

NAS6604

120

NAS 6600 Bolts

5/16-24

NAS6605

240

NAS 600 THRU 606 Screws

NAS 623 Screws

3/8-24

NAS6606

350

NAS 1351 Screws

NAS 1352 Screws

7/16-20

NAS6607

665

1/2-20

NAS6608

995

AN3 Bolts

10-32

AN3

AN4 Bolts

AN6 Bolts

AN8 Bolts

1/4-28

AN4

AN502 Screws

AN503 Screws

AN509 Screws

3/8-24

AN6

280

AN525 Screws

MS24694 Screws

1/2-20

AN8

795

MS27039 Screws

10-32

B330-7 (MS27151-7)

6 to 15

1/4-28

B330-13 (MS27151-13)

11 to 25

5/16-24

B330-16 (MS27151-16)

20 to 40

STAMPED NUTS

(PALNUTS)

3/8-24

B330-19 (MS27151-19)

29 to 60

7/16-20

B330-21 (MS27151-21)

42 to 85

1/2-20

B330-24 (MS27151-24)

54 to 110

1/8-27

N/A

1/4-18

N/A

TAPERED PIPE

3/8-18

N/A

110

THREADS

1/2-14

N/A

160

3/4-14

N/A

230

10-32

AN315-3

1/4-28

AN316-4

ROD END JAM NUTS

(AN315 and AN316)

5/16-24

AN316-5

3/8-24

AN316-6

110

Values include nut self-locking torque.

Increase values 10% if torqued at bolt head.

For elbow & tee fittings which require alignment, torque to indicated value then tighten to desired position.

Values ± 10% unless range is specified.

Unless otherwise noted, thread sizes 8-32 & smaller are not used for primary structure & do not require specific

torque.

Page 20.6

Chapter 20 Standard Practices

20-33 Special Torques

Special torques supersede standard torques listed in Section 20-32.

TORQUE

AREA*

FASTENER*

(IN.-LB)*

(1) D795-8 line assembly, B-nuts

150

(1) D799-2 switch assembly

(1) D799-3 switch assembly

(1) G783-1 condenser, dessicant cap

100

(1) G784-1 evaporator assembly, inlet B-nut to 134-32 TXV

210

AIR CONDITIONING

(1) G794-1 hose assembly, B-nuts

210

(OPTIONAL

(1) G794-2 hose assembly, B-nuts

210

EQUIPMENT)

(1) G794-3 hose assembly, B-nuts

150

(1) G810-1 line assembly, B-nuts

210

(1) G811-1 line assembly, B-nuts

210

(2) AN924-8D nuts

360

(2) 91292A135 screws

CABIN

(1) MS21042L5 nut, ground handling ball

240

(1) B289-2 bolt, drain

(1) B563-2 sight gage

150

(1) D205-19 hose assembly, B-nuts

270-300

(1) D205-20 hose assembly, B-nuts

270-300

(1) F723-1 line assembly, B-nuts

330-360

(1) F723-2 line assembly, B-nuts

230-260

(1) F723-3 line assembly, B-nuts

230-260

(1) F723-4 line assembly, B-nuts

230-260

COOLING SYSTEM

(1) F724-1 line assembly, B-nuts

110-130

(ENGINE AND MAIN

(1) F724-2 line assembly, B-nuts

110-130

ROTOR GEARBOX

OILS)

(1) F724-3 line assembly, B-nuts

110-130

(2) AN815-8D unions, on F649-1 oil cooler

230-260

(2) AN832-8D unions, at firewall

230-260

(1) AN832-10D union, at firewall

330-360

(2) AN924-8D nuts, at firewall

230-260

(1) AN924-10D nut, at firewall

330-360

(2) AN926-6D nuts, securing F823-1 thermostat assembly to firewall

110-130

(2) AS5169D04L fitting, on F649-1 oil cooler

50-65

(1) MS28034-1 oil temperature sender, to tank

120

(16) MS51861-37C screws, securing door hinge assemblies

(2) 94830A030 nuts, securing G904-1 gas spring ball studs at

DOOR HINGES AND

100

baggage compartment door

GAS SPRINGS

(2) 94830A030 nuts, securing G394-1 gas spring ball studs at aft

100

doors

Chapter 20 Standard Practices

Page 20.7

20-33 Special Torques (continued)

TORQUE

AREA*

FASTENER*

(IN.-LB)*

(2) C394-2 ball stud, at forward doors, to frame

150 wet

DOOR HINGES AND

(2) D575-2 and (2) D575-3 ball joints, at forward doors' D573-4

GAS SPRINGS

rods

(2) F650-1 bolt, forward main rotor gearbox and G201 frame

90 FT-LB

mounts

Bolt head or nut

DRIVE SYSTEM

(2) F650-2 bolt, aft main rotor gearbox and G201 frame mounts

90 FT-LB

Bolt head or nut

(4) MS20074-04-06 bolts, at tail rotor gearbox C112-1 output cap

(8) NAS6604-6 bolts, securing vertical stabilizers to upper horizontal

150

stabilizer

EMPENNAGE

(1) NAS1352-3-14P screw, securing guard assembly blocks to

lower vertical stabilizer

(1) Fuel control unit (FCU) lever nut

40-50

ENGINE CONTROLS

(1) Power turbine governor (PTG) lever nut

40-50

(1) AN316-7R nut, compressor service line

150

ENGINE INDUCTION

(1) AN929-4 cap, compressor service line

(5) B289-1 bolts, fuel sender

(1) B330-6 palnut, fuel sender center stud

(1) G254-2 fitting, vent assembly

200

(1) G254-6 retainer, vent assembly

200

FUEL SYSTEM

(1) MS21042L3 nut, securing fuel valve control wire

(1) B254-3 strainer, fuel bladder outlet

150

(1) D205-21 hose assembly, fuel bladder outlet to fuel valve, B-nuts

110-130

(1) AN924-5D nut, low fuel warning switch assembly

150

(1) B283-12 hose assembly, fuel valve to fuel pump inlet, B-nuts

110-130

(1) G391-1 line assembly B-nuts

230-260

(1) G391-2 line assembly B-nuts

100

(1) G391-3 line assembly B-nuts

100

HEATER

(1) G391-4 line assembly B-nuts

100

(1) G391-5 line assembly B-nuts

230-260

(1) MS21042L3 nut, securing control wire

25-30

(1) AN820-4 cap, on reservoir AN804D4 T-fitting

(1) AN820-6 cap, on reservoir AN834-6D T-fitting

120

(2) AN818-4D nuts, F902-1 line assembly and right hand servo

135-150

HYDRAULIC HOSES

(2) AN818-6D nuts, F902-2 line assembly and right hand servo

110-130

& FITTINGS

(2) D452-3 nuts, on aft and left hand servos

(3) D452-4 nuts, on aft and left hand servos and on reservoir

(1) D452-6 nut, on reservoir

150

(2) B330-19 palnut, on aft and left hand servos

Page 20.8

Chapter 20 Standard Practices

20-33 Special Torques (continued)

TORQUE

AREA*

FASTENER*

(IN.-LB)*

(3) B330-21 palnut, on aft and left servos and on reservoir

(1) B330-25 palnut, on reservoir

(1) D205-14 line assembly B-nuts

95-105

HYDRAULIC HOSES

(1) D205-17 line assembly B-nuts

95-105

& FITTINGS

(1) D205-18 line assembly B-nuts

135-150

(1) D205-22 line assembly B-nuts

95-105

(1) D205-23 line assembly B-nuts

135-150

(1) D205-24 line assembly B-nuts

135-150

(1) D487-3, filler-vent

100

HYDRAULIC

(1) D516-1, filter cap

150

RESERVOIR

(1) B563-3, sight gage

150

HYDRAULIC

(1) MS21042L08 nut, attaching D200-2 scissors

SERVOS

(1) B330-6 palnut on D200-2 scissor apex fastener

5-10

(4) NAS6604-46 bolts, securing ground handling wheel

support weldments to skid tubes

(2) NAS6607P44 bolt, securing shackles to fuselage

66 FT-LB

LANDING GEAR

(4) NAS607P20 bolt, securing landing gear to fuselage

66 FT-LB

supports and shackles

(4) B277-28 clamp, securing fairings to struts

(1) D674-2 hose assembly, B-nuts

230-260

(1) D674-6 hose assembly, B-nuts

230-260

(1) D674-7 hose assembly, B-nuts

110-130

POP-OUT FLOATS

(OPTIONAL

(1) D674-9 hose assembly, B-nuts

230-260

EQUIPMENT)

(1) D674-11 hose assembly, B-nuts

230-260

(1) D674-12 hose assembly, B-nuts

230-260

(1) D674-13 hose assembly, B-nuts

230-260

MAIN ROTOR

(2) B289-2 bolts, per blade, self-sealing

60-80

BLADE

(2) C722-3 screws, per blade, tip balance weight

MAIN ROTOR

(2) MS21042L04 nut, low rotor horn V3-1 switch

4-5

FLIGHT CONTROLS

(1) MS21245L8 nut, securing engine shaft input yoke to

50 FT-LB

main rotor gearbox

(1) F904-1 pinion plug, securing rotor shaft input yoke to

30 FT-LB Wet

main rotor gearbox

Apply A257-9 to threads

(1) AN814-8D plug, main rotor gearbox filler plug

150

MAIN ROTOR

GEARBOX

(1) B254-3 strainer, main rotor gearbox sump

200

(1) D205-25 hose, sump to pump B-nuts

120

(1) B566-1 chip detector, main rotor gearbox

150

(1) chip detector wire terminal nut

4-6

(1) B563-2 sight gage

150

Chapter 20 Standard Practices

Page 20.9

20-33 Special Torques (continued)

TORQUE

AREA*

FASTENER*

(IN.-LB)*

New bolt: 0.021-0.022

inch elongation, wet

(1) NAS634-105 bolt, teeter hinge and

MAIN ROTOR HUB

Used bolt: 0.020-0.022

(2) NAS634-105 bolt, coning hinges

inch elongation, wet, and

cotter pin holes must align

MAST TUBE

(1) B277-064 clamp, lower rib to mast tube

PITCH LINKS

(2) 21FKF-813 self-locking jam nuts, main rotor pitch links

300

(1) D745-3 (pressure) switch assembly

(1) F147-1 screw, FCU minimum throttle stop

(1) F170-1 fitting, engine gearbox

100

(1) F727-1 line assembly, fuel pump drain

50-65

(1) F727-2 line assembly, horizontal turbine-firewall shield

50-65

assembly drain

(1) F741-1 line assembly, fuel differential pressure switch

75-85

(1) G426-1 (fuel differential pressure) switch assembly

100

(2) nuts, securing harness wire to MGT thermocouple

studs, engine-supplied

(2) nuts, securing harness wires to starter-generator small

terminals, starter-generator supplied

(2) nuts, securing harness wires to starter-generator large

180

terminals, starter-generator supplied

(1) nut, securing harness wire to ignition exciter box, engine-

POWERPLANT

supplied

(2) nuts, securing harness and (2) MS21919WCH4 clamps

to engine accesory gearbox, engine-supplied

(4) nuts, securing F577-1 bracket assembly, engine-supplied

(6) nuts, securing rear PTO cover to engine, engine-supplied

(2) tee bolts, securing F173-1 struts to engine, engine-

35-40

supplied

(2) AN815-8D unions, engine oil outlet and oil tank vent

250

(1) AN815-10D union, engine oil inlet

375

(1) AN919-0D reducer and (1) AN919-2D reducer

100

(6) NAS6605H3 bolts, securing (2) F593-1 support

110

assemblies to engine

(2) NAS6605H4 bolts and (1) NAS6605H2 bolt, securing

110

F593-3 plate to engine

(1) CV26-77 check valve, engine oil outlet (early R66s)

250

POWERPLANT

(3) MS21042L3 nuts, securing control wires

25-30

CONTROLS

(26) NAS1352N08-8 screws, securing spacers, sleeve

35 wet

SWASHPLATE

assembly, shield, and retainers

(2) NAS1352N08-4 screws, securing B769-2 bracket

Page 20.10

Chapter 20 Standard Practices

20-33 Special Torques (continued)

TORQUE

AREA*

FASTENER*

(IN.-LB)*

(1) MS21042L4 nut, securing C119-2 bumper

120

TAIL ROTOR

(1) NAS6606-53 bolt, teeter hinge

380

TAIL ROTOR

(1) MS21042L4 nut, outboard of F316-1 bellcrank assembly

FLIGHT CONTROLS

(1) A610-1 vent assembly

100

(1) B563-1 sight gage

150

(1) B566-2 chip detector

100

(1) AN320-8 nut, input yoke

35-45 FT-LB

TAIL ROTOR

(4) MS20074-04-06 bolts, input cap

GEARBOX

(8) MS20074-04-06 bolts, input housing and output cap

100

(1) MS21042L5 nut, pitch control housing

240

(4) NAS1352-5-12P bolts (undrilled), gearbox-to-tailcone

240

attachment

TAIL ROTOR

(1) NAS1352-3-14P screw, securing block assembly to

GUARD

stabilizer

WINDOWS

(22) AN526C832R12 screw, thru center brace

1. Values include nut self-locking torque.

2. Increase values 10% if torqued at bolt head.

3. For elbow & tee fittings which require alignment, torque to indicated value then tighten to desired position.

4. Values ± 10% unless range is specified.

5. Unless otherwise noted, thread sizes 8-32 & smaller are not used for primary structure & do not require

specific torque.

20-34 Push-Pull Tube Rod End Adjustment

NOTE

Refer to Section 18-13 to adjust C258-1 main rotor pitch links.

The following procedure is standard for adjusting push-pull tube rod ends:

1. Loosen palnut and jam nut on rod end shank.

2. Remove hardware securing push-pull tube rod end to attachment point per respective

instructions.

3. Screw rod end in or out of push-pull tube as required to obtain proper rigging

adjustment.

4. After any rod end adjustment, verify rod end threaded shank blocks passage of 0.020-

inch diameter wire thru the witness hole in the push-pull tube per Figure 5-1. When no

witness hole is provided, refer to Figure 5-1 for maximum rod end extension.

5. Install fastener securing push-pull tube to attachment point per respective instructions.

6. Refer to Figure 5-2. Position rod ends to allow as much push-pull tube rotation as

possible without binding. Standard torque jam nuts & palnuts per Section 20-32 &

torque stripe per Figure 5-1.

Chapter 20 Standard Practices

Page 20.11

20-40 Non-Destructive Testing

WARNING

Refer to appropriate Material Safety Data Sheet (MSDS) and

take necessary safety precautions when working in proximity to

hazardous materials.

20-41 Magnetic Particle Inspection

Ferromagnetic steel parts must be inspected for structural defects using magnetic particle

inspection.

Steel parts covered by this specification shall be inspected per ASTM E 1444 wet process

with ultra-violet light. Applicable requirements and limitations of the above standard shall

apply. Parts shall be thoroughly demagnetized and cleaned after inspections. Record the

size and location of all rejectable indications.

Procedures and equipment used to perform the inspection shall conform to requirements

of ASTM E 1444. Whenever possible, parts shall be inspected with both circular and

longitudinal magnetization.

A. Inspection Criteria

Parts

(except gears) which are inspected by magnetic particle inspection shall be

accepted or rejected according to the following criteria:

Acceptable indications:

yy Indications smaller than 0.015 inch are not considered ratable.

yy Indications caused by sharp changes in cross-section or part geometry.

Rejectable indications:

yy Indications interpreted as cracks, seams, laps, shuts, or any flaws which are open

to the surface.

yy Indications oriented at an angle of more than 15 degrees from the longitudinal axis

with length exceeding 0.125 inch.

yy Circumferential indications on any shoulder or fillet (changes in diameter).

yy Any indications which break over an edge, shoulder, fillet radius, keyway, spline, or

an adjacent area of part more than 0.015 inch.

yy Indications caused by undercuts at the toe of a weld.

yy Indications caused by cracks in the weld or parent metal.

yy Indications caused by inclusions in weld material exceeding 0.1 inch in length.

Page 20.12

Chapter 20 Standard Practices

20-42 Fluorescent Penetrant Inspection

This specification provides for surface inspection of parts fabricated from nonmagnetic

materials to detect discontinuities open to the surface, such as cracks, cold shuts, laps,

porosity and other surface defects.

Applicable requirements and limitations of ASTM E 1417 shall apply. After inspection is

complete, solvent clean parts.

The step-by-step procedure and equipment used to perform the inspection shall be

accomplished per ASTM E 1417.

A. Inspection Criteria

Parts inspected by fluorescent penetrant method shall be accepted or rejected on basis

of acceptance limits specified. If acceptance limits are not specified, rejectable surface

defects and any of the following:

yy Cracks

yy Seams

yy Cold shuts or laps

yy Surface inclusions

yy In castings, aligned discontinuous surface indications other than cracks, cold shuts

and inclusions are rejectable if more than 3/8 inch in length.

20-50 Corrosion Control

[Reserved].

20-60 Priming and Painting

WARNING

Refer to appropriate Material Safety Data Sheet (MSDS) and

take necessary safety precautions when working in proximity to

hazardous materials.

A. Priming

This specification outlines preparation and application requirements for primers. Primers

provide corrosion protection and a final finish or a base for the final finish.

25 OCT 2010

Chapter 20 Standard Practices

Page 20.13

20-60 Priming and Painting (continued)

A. Priming (continued)

Use only approved materials listed in Section 20-70. Parts shall be prepared in the following

manner:

Preparing Aluminum

Unless otherwise specified, chemical conversion coating using Alodine 1201 is the

standard treatment before priming aluminum. Follow manufacturers instructions for

application of Alodine. However, if bare or clad aluminum is primed without conversion

coating, the following procedure must be used:

a. Alkaline clean if immersion is practical, otherwise wipe clean with QSOL 220 or

equivalent degreasing agent.

b. Lightly scuff the surface with Scotch Brite pads.

c. Wipe with a tack rag to remove any foreign material or damp wipe with QSOL 220

or equivalent solvent.

d. Air dry. Do not touch parts with bare hands until primed.

Preparing Steel

Alkaline clean is the preferred method for cleaning steel except where immersion is not

practical. For extremely greasy or dirty steel parts a preclean in a solvent vapor bath

using Perchloroethylene, or hand wipe with QSOL 220 and air dry may be used on a

limited basis.

If a solvent vapor bath is selected, a degreaser which incorporates a spray flushing

nozzle must be utilized except for specific parts noted herein. Clean steel parts by:

a. Immerse parts in a solvent vapor bath for 3-5 minutes to loosen all dirt, oil and

grease.

b. After vapor bath, spray all holes, cavities, and recesses with clean liquid solvent

from a pressurized nozzle to thoroughly flush and remove any debris.

c. Air dry thoroughly using filtered, dry, compressed air.

d. Wrap parts in clean paper or hang from racks to retain cleanliness until ready for

priming. Do not touch parts with bare hands until primed.

Application

Apply primer after mixing per manufacturer’s recommendations. Total primer coating

is not to exceed 0.005 inch thickness. For parts with internal openings, such as tubes,

prime the inside as follows:

a. Thin primer to watery consistency using required reducer.

b. Pour in primer, slosh around, then drain immediately.

c. Dry parts at least (6) hours before using.

Inspection

Inspect for complete coverage and excessive thickness. If primer is excessively thick,

strip part using plastic media blast and re-prime.

Page 20.14

Chapter 20 Standard Practices

25 OCT 2010

20-60 Priming and Painting (continued)

B. Painting

This specification provides final paint finish requirements.

Do not prime or paint with a top coat finish the following areas (unless directed):

yy Sliding friction joints.

yy Stainless steel parts.

yy Swivel joints and adjustable rod ends.

yy Plastic, rubber, electrical components and wires or similar materials.

yy Bolted joints where torque is a specific requirement for clamping action.

yy Bearing press fit or close tolerance slip fit joints (except where wet chromate primer is

part of the assembly procedure).

1. Prior to paint application, clean and prime surface per Part A.

2. Painting Sequence - In general, most parts will be cleaned and primed as detail parts,

however, in some cases, such as the gearbox assembly, this will not be practical and

priming and painting may be done as an assembly.

25 OCT 2010

Chapter 20 Standard Practices

Page 20.15

20-70 Approved Materials

The following items are available from the noted manufacturer(s) or their distributor(s). Check

with appropriate regulatory authority(s) for allowable usage of materials.

WARNING

Refer to appropriate Material Safety Data Sheet (MSDS) and

take necessary safety precautions when working in proximity to

hazardous materials.

CAUTION

Follow product manufacturer’s instructions for handling and

storage.

20-71 Paint Strippers

PRODUCT

MANUFACTURER/SUPPLIER

APPLICATION

Cee-Bee Stripper

McGean-Rohco: Cee-Bee Division

Metal parts, except blades and flex plates.

A-292

Downey, CA

Plastic Media

Pauli & Griffin Co.

Metal parts except blades and unsupported

Blasting System

Vacaville, CA

sheet metal less than 0.040 inch thick.

20-72 Solvents and Cleaners

Product

Manufacturer/Supplier

Application

QSOL 220

Safety-Kleen Systems, Inc.

General use for cleaning prior to applying

Plano, TX

primer, topcoat, adhesive, or sealant.

Benzene, 1-Chloro-4

Any

“ “

(Trifluoromethyl)

PCBTF

Final Klean 3909S

Du Pont Chemical

“ “

Los Angeles, CA

EM-Citro*

LPS Laboratories, Inc.

“ “

Tucker, GA

Acetone

Any

“ “

Lacolene

Any

Acrylic plastic cleaner only.

(Aliphatic

Hydrocarbon)

Presolve

LPS Laboratories, Inc.

Hydraulic components only.

Tucker, GA

Tetrachloroethylene

Any

Vapor degreaser.

(Perchloroethylene)

Page 20.16

Chapter 20 Standard Practices

25 OCT 2010

20-72 Solvents and Cleaners (continued)

Product

Manufacturer/Supplier

Application

815 GD

Brulin Corporation

Ultrasonic cleaning, general use.**

Indianapolis, IN

SF50

L&R Mfg. Co.

“ “

Kearny, NJ

#112 Ammoniated or

L&R Mfg. Co.

Ultrasonic cleaning, avionics components

#222 Nonammoniated

Kearny, NJ

only.

cleaning & rinse solution

*May be used on acrylic plastic.

**Mix 5%-20% by volume; titration not required.

20-73 Fillers and Putty

Product

Manufacturer/Supplier

Application

315 Putty & Blue Cream

DuPont

Minor surface imperfections.

Hardener

Los Angeles, CA

051144-05960 Acryl -

3M Co.

“ “

Green Spot Putty

St. Paul, MN

SBF1191

Gearhead Products

“ “

Indianapolis, IN

20-74 Torque Seal

PRODUCT

MANUFACTURER/SUPPLIER

APPLICATION

F-900

Organic Products Co.

Torque seal.

(Any color except red)

Irving, TX

20-75 Primers

PRODUCT

MANUFACTURER/SUPPLIER

APPLICATION

Gray epoxy CA 7501

Desoto Aerospace Coatings,

Unlimited.

with CA 7501B activator

PRC - Desoto Int., Inc.

Glendale, CA

Gray epoxy 44-GY-79

Deft, Inc.

Aluminum parts and assemblies, and

with 44-GY-79 activator

Irvine, CA

fiberglass parts.

Aviation Primer, Green,

Valspar Corporation

Limited or touch-up use only.

A902 (Aerosol)*

Medina, OH

*Shelf life two years

25 OCT 2010

Chapter 20 Standard Practices

Page 20.17

20-76 Powder Coat

Epoxy and topcoat powders are electrostatically applied to steel parts and baked for 10-15

minutes after each powder application. Curing temperature must not exceed 400° F.

Zinc rich epoxy powder coating thickness allowance is 0.001 to 0.004 inches.

PRODUCT

MANUFACTURER

13-7004 Corvel Grey

Dow Chemical Co.

Zinc-Rich Epoxy Powder*

81-2158 Vitralon Grey

Pratt & Lambert Chemical Coatings

Zinc-Rich Epoxy Powder*

Buffalo, NY

Total coating thickness allowance is 0.003 to 0.007 inches (epoxy and topcoat). Coating

may exceed maximum thickness in local areas due to part geometry.

PRODUCT

MANUFACTURER

39/80020 Smooth Matte

Tiger Drylac USA

Black

Cucamonga, CA

Polyester Topcoat Powder*

49/72460 Smooth Glossy

“ “

Gray RAL 7043

Polyester Topcoat Powder*

49/22460 Smooth Glossy

“ “

Yellow RAL 1028

Polyester Topcoat Powder*

PFWF104S9 White

Dupont Co.

Wilmington, DE

*Shelf life: 12 months from date of manufacture at ambient temperature.

Page 20.18

Chapter 20 Standard Practices

25 OCT 2010

20-77 Paints

Refer to Figures 20-3 and 20-4 for finish code locations. Paint codes for specific helicopter

serial numbers are listed in the front of factory-supplied R66 Airframe Maintenance Record

(AMR; logbook).

NOTE

Use fisheye eliminator, accelerator, or other additives per

manufacturer's recommendations.

CODE

MATERIAL

MANUFACTURER

Flat Black Imron 373-P-29950

E.I. DuPont de Nemours & Co.

Polyurethane enamel with 193S or 8909S activator & 8685S reducer

Los Angeles, CA

Semi-gloss Black 3900-05 with 39-SG

Cardinal Industrial Finishes

Catalyst and water reducer

El Monte, CA

Dark gray Imron 5000/6000

E.I. DuPont de Nemours & Co.

Polyurethane enamel with 193S or 8909S activator & 8685S reducer

Los Angeles, CA

White Imron 5000/6000

“ “

Polyurethane enamel with 193S or 8909S activator & 8685S reducer

Yellow Imron 5000/6000

“ “

Polyurethane enamel with 193S or 8909S activator & 8685S reducer

Imron polyurethane enamel tint(s) with 193S or 8909S activator &

E.I. DuPont de Nemours & Co.

8685S reducer

Los Angeles, CA

Clear Imron 3480S or 2400S with 193S or 8909S activator

“ “

Clear Imron 3480S or 2400S (1-part) and RK-P-19478 (11-parts) with

“ “

193S or 8909S activator (4-parts)

White Imron 2.1 FT flat

“ “

Polyurethane enamel with FG-1333 activator and T-1021 or T-1022

thinner

White Cat-L-Ink 50-100R (shelf life 3 years)

Ethone, Inc.

20/A Catalyst (shelf life 2 years)

West Haven, CT

Yellow Cat-L-Ink 50-202AR or BR (shelf life 3 years)

“ “

20/A Catalyst (shelf life 2 years)

Red Imron 5000/6000

E.I. DuPont de Nemours & Co.

Polyurethane enamel with 193S or 8909S activator & 8685S reducer

Los Angeles, CA

Orange Imron 5000/6000

“ “

Polyurethane enamel with 193S or 8909S activator & 8685S reducer

Krylon 1311 (shelf life 2 years)

Krylon Div. of Borden

Matte clear (aerosol can)

Columbus, OH

For limited touch-up of interior and landing gear only:

CODE

MATERIAL

MANUFACTURER

Krylon 1613 (shelf life 2 years)

Krylon Div. of Borden

Semi-Flat Black (aerosol can)

Columbus, OH

NYBC 14 (shelf life 2 years)

New York Bronze Powder Co.

Semi-Flat Black

Scranton, PA

Cardinal A-2000-05

Cardinal Industrial Finishes

Flat Black (aerosol can)

So. El Monte, CA

25 OCT 2010

Chapter 20 Standard Practices

Page 20.19

20-78 Lubricants

RHC Part No.

Mfr. Part No.

Manufacturer

A257-1

101

Southwestern Petroleum Corp.

(general purpose grease)

Fort Worth, TX

A257-3

Aero Shell 14

Shell Oil Co.

MIL-G-25537 (grease)

A257-4

Dexron II or

Quaker State or Pennzoil

Dexron II/Mercon or

Dexron III/Mercon

(automatic transmission fluid)

A257-5

3120

Sta-Lube, Inc.

(water-resistant grease)

Compton, CA

11402

Lubrimatic

(water-resistant grease)

Buffalo Grove, IL

A257-6

Fuelube

Fleet Supplies Inc.

(fuel-resistant grease)

Cleveland, OH

EZ Turn

United-Erie Div. of Interstate Chemical Co.

(fuel-resistant grease)

Erie, PA

A257-7

Lubri-Kote Type A 1040 CR

Mealey Ind. Lubricants

(dry film lubricant)

Cleveland, OH

A257-8

P-80

International Products Corp.

(rubber lubricant)

Trenton, NJ

A257-9

Silver Grade

Loctite Corp.

(anti-seize)

Newington, CT

A257-15

MIL-PRF-5606

Any

(hydraulic fluid)

A257-19

111

Dow Corning Corp.

(valve lube & sealant compound)

Midland, MI

A257-20

Pag Oil

Apollo America Corp.

Daphne Hermetic PR

Southfield, MI

A257-21

P-16

Panef Corp.

(petrolatum lubricant)

Milwaukee, WI

A257-22

Mobil SHC 629

Exxon Mobil Corp.

(synthetic gear oil)

A257-23

AS 5780 HPC

Any

Class HTS (turbine oil)

Page 20.22

Chapter 20 Standard Practices

20-79 Adhesives and Sealants

RHC Part

Description

Color

Mfr. Part No.

Manufacturer

No.

B270-1

Sealant - polysulfide, fuel resistant

Gray

FS-8907 B-2

PPG Aerospace

(2-part)

Glendale, CA

Sealant - polysulfide, fuel resistant

Gray

AC-350 B-2

Advanced Chemistry

(2-part)

& Technology Inc.,

Garden Grove, CA

B270-5

Sealant - synthetic rubber putty

White

Q4-2805

Dow Corning Corp.

(1-part)

Light Gray

94-031

Midland, MI

B270-6

Sealant & lubricant - thread

Gray

Titeseal 55

Radiator Spec. Co.

(1-part)

Charlotte, NC

B270-8

Adhesive - rubber, nitrile/acetone

Tan

C 160

Stabond Corp.

(1-part)

Gardena, CA

B270-9

Adhesive - epoxy, structural,

Gray

2216 B/A

3M Co.

flexible (2-part)

St. Paul, MN

B270-10

Adhesive/sealant - threadlocker,

Red

271

Henkel Loctite Corp.

anaerobic (tight-fits) (1-part)

Rocky Hill, CT

B270-11

Adhesive/sealant - threadlocker,

Red

277

Henkel Loctite Corp.

anaerobic (loose-fits) (1-part)

Rocky Hill, CT

B270-12

Sealant - electrical potting (2-part)

Any color

MIL-PRF-8516

Any

except red

Type II, Class 2,

Category A or B

B270-13

Sealant - silicone rubber, electronic

Translucent

3145

Dow Corning Corp.

use (1-part)

Midland, MI

B270-14*

Adhesive - foam, neoprene/water

White

100 Neutral

3M Co.

(1-part)

Lavender

100 Lavender

St. Paul, MN

B270-15

Adhesive - plastic, for vinyl

Clear

2262

3M Co.

(1-part)

St. Paul, MN

B270-17

Adhesive - cyanoacrylate, instant

Clear

Super Bonder

Henkel Loctite Corp.

(1-part)

495

Rocky Hill, CT

B270-18

Adhesive - weather strip (1-part)

Black

051135-08008

3M Co.

St. Paul, MN

B270-19

Adhesive - epoxy structural, rigid

Green

1838 B/A

3M Co.

(2-part)

St. Paul, MN

B270-20

Adhesive/sealant - threadlocker,

Purple

222 or 222MS

Henkel Loctite Corp.

anaerobic, non-permanent (1-part)

Rocky Hill, CT

B270-21

Protectant - corrosion, non-drying

Lt. Amber

LPS 3

LPS Laboratories, Inc.

(1-part)

Tucker, GA

B270-22

Protectant - corrosion, drying

Amber

LPS Hardcoat

LPS Laboratories, Inc.

(1-part)

Tucker, GA

* B270-8 may be substituted for B270-14.

Chapter 20 Standard Practices

Page 20.23

20-79 Adhesives and Sealants (continued)

RHC Part

Description

Color

Mfr. Part No.

Manufacturer

No.

B270-23

Sealant - gasket (1-part)

Brown

GM3H

Perfect Seal

(Gasket Maker #4)

Sealant - gasket (1-part)

Brown

JV66B

Dana Corp.;

Churubusco, IN

(Victor Reinz Brand)

B270-24

Activator/Primer -

Translucent

7649

Henkel Loctite Corp.

Anaerobic adhesive (1-part)

Green

Rocky Hill, CT

B270-25

Clear Coat - automotive

Clear

Clear Coat

Automotivetouchup

touch up, brush in bottle

Touch up Bottle

Harahan, LA

(1-part)

B270-26

Sealant - Polysulfide,

Black

AC-251B-1

Advanced Chemistry &

window glazing (2-Part)

Technology Inc.,

Garden Grove, CA

20-80 Storage Limits

1. P/N B283-x hoses have a shelf storage life of 5 years. Hose service life is “on condition”,

with a maximum of 12 years or 2000 hours, whichever occurs first.

2. Elastic cords have a shelf storage life of 5 years. Elastic cord service life is “on condition”,

with a maximum of 12 years. Use invoice or FAA Form 8130 date as start date.

3. Store V-belts at less than 85ºF (30ºC), with relative humidity below 70%. Avoid solvent

and oil vapors, atmospheric contaminants, sunlight, and ozone sources (electric motors, arc

welding, ionizing air purifiers, etc.). Belt shelf life is 4 years if preceding recommendations

are followed. Use invoice date or FAA Form 8130-3 date as start date.

4. Oils and greases have a 5 year shelf life when stored and kept sealed in their original

container. Use invoice date or FAA Form 8130-3 date as start date unless the manufacturer

has marked container with manufacture date (in which case use manufacture date as start

date).

5. Rubber o-rings, seals, and gaskets have a shelf storage life of 20 quarters (5 years). Service

life is “on condition” with a maximum of 12 years. Use cure date on package as start

date.

6. Store fuel cell (bladder) in temperatures above 45ºF and below 75ºF.

Page 20.24

Chapter 20 Standard Practices

20-90 Miscellaneous Practices

20-91 Part Interchangeability

The following parts are interchangeable. Unless noted otherwise, whenever one part is

referred to in this manual, its substitute part is also permitted.

Part

Interchangeable with:

354601 & 354602

D262-1 & D262-2

AN340 nut

MS35649 nut per NASM35649 except AN340B8 nut

AN345 nut

MS35650 nut per NASM35650

AN364 nut

MS21083 nut per NASM21083

AN507 screw

MS24693 screw per NASM24693

AN509 screw

MS24694 screw per NASM24694

AN515 screw

MS35206 screw per NASM35206

AN515C screw

MS51957 screw

AN515UB screw

B567-__ screw

AN525 & AN526 screw

MS27039C screw per NASM27039

AN814 & MS24391 plug

AS5169 plug

AN815 & MS24392 union

AS5174 union

AN819 & MS20819 sleeve

AS5176 sleeve

AN822 & MS20822 elbow

AS5195 elbow

AN823 & MS20823 elbow

AS5196 elbow

AN825 & MS20825 tee

AS5197 tee

AN826 & MS20826 tee

AS5198 tee

AN894 & MS24398 bushing

AS5173 bushing

AN900 gasket

MS35769 gasket per AS35769

AN924 nut & MS24400 nut

AS5178 nut

AN931 grommet

MS35489 grommet

AN935 lockwasher

B332-__ lockwasher

AN936 lockwasher

MS35335 lockwasher

AN960-4L washer

NAS1149FN416P washer

AN960-4 washer

NAS1149FN432P washer

AN960-6L washer

NAS1149FN616P washer

AN960-6 washer

NAS1149FN632P washer

AN960-8L washer

NAS1149FN816P washer

AN960-8 washer

NAS1149FN832P washer

AN960-10L washer

NAS1149F0332P washer

AN960-10 washer

NAS1149F0363P washer

AN960-416L washer

NAS1149F0432P washer

AN960-416 washer

NAS1149F0463P washer

AN960-516L washer

NAS1149F0532P washer

AN960-516 washer

NAS1149F0563P washer

AN960-616L washer

NAS1149F0632P washer

AN960-616 washer

NAS1149F0663P washer

AN960-816L washer

NAS1149F0816P washer

AN960-816 washer

NAS1149F0832P washer

AN960-1016L washer

NAS1149F1032P washer

AN960-1016 washer

NAS1149F1063P washer

AN960PD8L washer

NAS1149DN816P washer

AN960PD416L washer

NAS1149D0416J washer

AN960PD516L washer

NAS1149D0516J washer

AN960PD616L washer

NAS1149D0616J washer

AVDEL 1693 rivet

AVDEL 1691 rivet

MS20604ML4W1 rivet

MS20604M4W1 rivet per NASM20604

MS21919DG_ clamp

MS21919WDG_ clamp or AS21919 clamp

NAS1291 nut

MS21042L_ nut per NASM21042

NAS1303 thru NAS1320 bolt

NAS6603 thru NAS6620 bolt*

NAS487 instrument nut

MS33737 Instrument nut per NASM33737

NAS679A nut

NAS1291- nut or MS21042L_ nut per NASM21042

NAS679C M nut

NAS1291C M nut

NAS696 nutplate

MS21071 nutplate per NASM21071

NAS698 nutplate

MS21073 nutplate per NASM21073

*The following bolts must be NAS1300 series only: NAS1304-17, -28, -35, -37, & -38, and NAS1305-35.

25 OCT 2010

Chapter 20 Standard Practices

Page 20.25

20-92 Thermal Fitting Parts

General Procedures for using heat to fit parts during assembly or evaluating parts that may

have been overheated in service:

Aluminum parts must not be heated above 200ºF for more than 5 minutes. Higher

temperatures or longer times adversely affect strength and corrosion properties. Scrap any

aluminum parts suspected of going above 325ºF regardless of time at temperature.

Steel parts (bare) - Maximum temperature 300ºF. Higher temperature can reduce the

strength or cause temper brittleness in some alloys.

Steel parts (cadmium plated) - Maximum temperature 300ºF. Higher temperatures

will melt the plating and adversely affect steel strength by a process called liquid metal

embrittlement.

Bearings and carburized parts such as gears, clutch shafts, and clutch housings should

not be heated above 300ºF. Higher temperatures will reduce the surface hardness and

increase wear rates.

Always heat parts in an oven with temperature control set no greater than the maximum

temperature allowed for the part.

Always attach a pyrometer and thermocouple to the smallest aluminum part in the oven.

Never depend on the oven control to determine part temperature.

Cooling a part for thermal fitting at assembly is not recommended. Water vapor from the

air will condense on the part and frequently introduce water into the assembly causing

severe internal corrosion over time.

20-93 Replacement Component Identification (Data) Plates

In order to issue a replacement component identification plate for field installation, RHC

must first receive the old identification plate in legible condition. If old identification plate

is lost or destroyed, then RHC must have an original letter (photocopies or faxes are

NOT acceptable) from customer’s Civil Aviation Authority authorizing identification plate

replacement AND stating component name, part number, and serial number for each

requested identification plate. There is a charge for each plate issued.

Identification plates may be carefully removed using a sharp plastic scraper. If necessary,

use a heat gun to soften plate adhesive. Retain in a dry, contaminate-free area until ready

for reinstallation.

Damp wipe local area with acetone or equivalent solvent prior to reinstallation. Residual

adhesive on identification plate is usually sufficient for good adhesion. If necessary, use

B270-9 adhesive or equivalent to secure.

Page 20.26

Chapter 20 Standard Practices

25 OCT 2010

CHAPTER 21

ENVIRONMENT CONTROL

21-00 Description

Fresh air vents are located in each door and in the nose. Door vents are opened and closed

using the knob near the vent door hinge. A rotating knob is provided to seal and lock vents

closed. For maximum ventilation, open door vents wide during hover but only one inch or less

during cruise. The rotating knob can be used to hold vents partially open.

See Chapter 52 for door vent maintenance instructions.

The fresh air inlet in the nose is opened by pulling the vent handle on the console face. Rotating

the vent handle clockwise will lock its position. Air from the nose inlet is directed along the

inside surface of the windshield for defogging as well as for ventilation.

The optional cabin air conditioning system, shown schematically in Figure 21-2, is similar to

conventional automotive and light aircraft systems. The system consists of a compressor

mounted immediately aft of the main gearbox, a condenser mounted to the vertical firewall

in the engine compartment, an evaporator mounted to the front of the center seat support, a

blower, an overhead outlet duct, and interconnecting lines and hoses. The system uses R134a

refrigerant.

The compressor is belt-driven, by a pulley mounted to the main gearbox tail rotor drive yoke

assembly, and is equipped with an electromagnetic clutch. When the system is off, the

compressor clutch is disengaged, allowing the compressor pulley to freewheel.

Cooling air for the condenser is supplied via an opening in the belly. The engine cowling air

scoop collects the necessary cooling air for the condenser during forward flight. In a hover,

electric fans help to draw cooling air through the condenser.

The evaporator blower draws warm cabin air though the evaporator inlet grill and evaporator,

where the air is cooled. Cool air is drawn through the blower and blown through ducts under

the center seat, up the cabin aft wall, and to the overhead duct.

The system is controlled by a toggle switch on the overhead duct which allows selection of off,

low, and high fan settings. The compressor is automatically engaged by switching the fan on.

A temperature (freeze) switch disengages the compressor when evaporator temperature drops

below freezing. Safety (pressure) switches disengage the compressor if excessive refrigerant

leakage occurs or if refrigerant pressure is excessive. When the collective is lowered to the

full-down position another switch disengages the compressor for 10 seconds to ensure that

aircraft performance is not affected. All circuits are protected by the 25 amp A/C circuit

breaker; the evaporator blower, the condenser fans, and the compressor clutch circuits are

further protected by fuses.

Bleed air from the engine compressor is used for cabin heat. Tubing routes hot air from the

engine to outlets forward of the tail rotor pedals and in the rear footwells. A heater control

knob located to the left of the cyclic stick actuates a valve in the aft end of the control tunnel

through a push-pull cable to control cabin heat. Because the cabin heat uses engine compressor

air, some performance degradation occurs with heat ON.

CAUTION

In case of engine fire, cabin heat should be turned off.

Chapter 21 Environment Control

Page 21.1

21-10 Ventilation

21-11 Nose Vent

Refer to R66 Illustrated Parts Catalog (IPC) Figures 21-1.

A. Removal

1. Remove hardware securing avionics face to F033-1 lower console and remove face.

Unscrew and remove radios. Remove hardware securing radio trays to lower console

and remove trays. Disconnect OAT wiring.

2. Refer to Figure 21-1. Remove screws attaching upper console to lower console and

hinge console aft. Protect instrument face with foam support or equivalent.

3. Remove and discard cotter pin securing clevis pin and C522-5 (air vent) control inner

wire to C062-1 vent box assembly channel. Remove and retain clevis pin.

4. Remove hardware securing AN742-3 clamp and control housing to vent box angle.

5. Cut and discard ty-rap securing control housing to lower console angle.

6. Remove screws securing C365-13 mount assembly to lower console and remove

control. As required, remove MS35489-4 grommet and clamp; remove jam nut

& lockwashers securing mount assembly to control housing, and remove mount

assembly.

Installation

Refer to Figure 21-1. As required, install C365-12 mount assembly, lockwashers,

and jam nut on C522-5 (air vent) control housing, but do not tighten jam nut. Install

AN742-3 clamp and (new, as required) MS35489-4 grommet on control housing.

Position control in lower console and install screws securing mount assembly to

lower console. Verify security.

Rotate control knob until horizontal within 15° when locked; tighten jam nut against

mount assembly. Verify security.

Route control inner wire through C062-1 vent box assembly channel. Adjust grommet

position as required, and install clevis pin through channel and control inner wire.

Install cotter pin. Verify security.

Install clamp and hardware securing clamp and control housing to vent box angle.

Install ty-rap around control housing through hole in lower console angle. Cinch ty-

rap until snug without over-tightening, and trim tip flush with head.

Actuate vent and adjust clamp position as required for proper vent operation. Verify

control housing does not slip through clamp when opening and closing vent. Verify

clearance under knob is 0.03-0.10 inch with knob fully depressed.

Close and secure upper console. Connect OAT wiring. Install radio trays and

hardware securing trays to lower console. Verify security. Install and secure radios.

Install avionics face and hardware securing face to lower console.

Chapter 21 Environment Control

Page 21.3

21-20 Air Conditioning

21-21 Compressor Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 21-3.

A. Belt Replacement

Remove tailcone cowling per Section 53-23.

Remove hardware securing F196-1 tail rotor drive fan shaft to C947-3 plate

assemblies, noting hardware removed.

Loosen hardware securing G777-1 compressor assembly to G781-1 arm weldment.

CAUTION

Do not use refrigerant hose assemblies or fittings to rotate

compressor. Do not rotate compressor further than necessary, to

avoid damaging system wiring and refrigerant hoses or fittings.

Rotate compressor down and inboard as required to disengage B173-5 v-belt from

pulleys. Route belt around drive shaft flange and remove belt.

Route new B173-5 v-belt around drive shaft flange and fit belt onto G779-1 pulley

and compressor pulley.

Rotate compressor up and outboard to tension belt, then tighten hardware securing

compressor to weldment. Adjust belt until 4.5-5.5 lb of force applied mid-span

deflects belt 0.16-inch. Standard torque bolts per Section 20-32 and torque stripe

per Figure 5-1.

Install hardware securing drive shaft to plate assemblies, as removed. Standard

torque bolts per Section 20-32 and torque stripe per Figure 5-1.

Install tailcone cowling per Section 53-23.

Chapter 21 Environment Control

Page 21.5

21-21 Compressor Assembly (continued)

Removal

1. Remove tailcone cowling per Section 53-23.

2. Turn BATTERY switch OFF. Cut and discard ty-raps as required and disconnect

compressor assembly wiring from airframe harness at connectors.

3. Recover refrigerant per Section 12-81. Remove hardware securing refrigerant hose

assemblies to G777-1 compressor assembly. Cap fittings.

4. Remove hardware securing compressor to G781-1 arm weldment and G782-1 mount

weldment and remove compressor.

C. Installation

Remove G777-1 compressor assembly service port caps and completely drain oil.

Using a syringe, service compressor with 3 oz A257-20 pag oil into the high pressure

port. Install service port caps; verify security.

Refer to Section 5-45. Inspect B173-5 v-belt condition and replace as required. Fit

belt around G779-1 pulley and compressor pulley, and install hardware securing

compressor to G782-1 mount weldment. Standard torque bolts per Section 20-32.

Install hardware securing compressor to G781-1 arm weldment. Rotate compressor

up and outboard to tension belt, then tighten hardware securing compressor to

weldment. Adjust belt until 4.5-5.5 lb of force applied mid-span deflects belt 0.16-

inch. Standard torque bolts per Section 20-32, and torque stripe all compressor

mounting hardware per Figure 5-1.

Remove caps and install refrigerant hose assemblies and hardware securing hoses to

compressor. Special torque screws per Section 20-33 and torque stripe per Figure

5-1.

Connect compressor assembly wiring to airframe harness at connectors and install

ty-raps as required. Cinch ty-raps until snug without over-tightening, and trim tips

flush with heads.

Perform leak detection per Section 12-83.

Charge system with refrigerant per Section 12-82.

Install tailcone cowling per Section 53-23.

Page 21.6

Chapter 21 Environment Control

21-22 Condenser and Fan Assemblies

Refer to R66 Illustrated Parts Catalog (IPC) Figure 21-7.

A. Removal

1. Recover refrigerant per Section 12-82.

2. Remove engine cowling per Section 53-21.

3. Turn BATTERY switch OFF. Cut and discard ty-raps as required and disconnect

G780-1 fan assembly wiring from airframe harness at connectors.

4. Remove hardware securing G786-1 box assembly to G783-1 condenser.

5. Using backup wrench, disconnect G810-1 and G811-1 line assembly b-nuts from

condenser fittings.

6. Supporting condenser, remove hardware securing condenser to G787 support

assemblies. Taking care not to damage line assemblies and condenser fittings,

carefully remove condenser. Cap fittings.

Installation

1. Remove caps. Install hardware securing G783-1 condenser to G787 support

assemblies. Verify security.

2. Connect G810-1 and G811-1 line assembly b-nuts to condenser fittings. Using

backup wrench, special torque b-nuts per Section 20-33, and torque stripe per Figure

5-1.

3. Install hardware securing G786-1 box assembly to condenser. Verify security.

4. Connect G780-1 fan assembly wiring to airframe harness at connectors and install

ty-raps as required. Cinch ty-raps until snug without over-tightening, and trim tips

flush with heads.

5. Perform leak detection per Section 12-83.

6. Charge system with refrigerant per Section 12-82.

7. Install engine cowling per Section 53-21.

Chapter 21 Environment Control

Page 21.7

21-23 Evaporator Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 21-11.

A. Removal

1. Recover refrigerant per Section 12-82.

2. Refer to Section 6-70. Detach F931-1 seat assembly (secured via hook and loop

tape) from F474-1 cover assembly and remove seat. Remove hardware securing

cover assembly and F380-8 angle to F377-1 middle seat assembly; remove cover

and angle.

3. Cut and discard ty-raps as required and disconnect D799-7 (freeze) switch assembly

wiring from airframe harness at connector.

4. Remove screws securing G798-1 cover assembly to seat assembly. Remove

hardware securing G784-1 evaporator assembly and switch to seat assembly.

5. Using backup wrench, disconnect D795-8 line assembly and evaporator line b-nuts

from G794 hose assemblies.

6. Remove aluminum tape securing F380-7 cover to middle seat (if installed). Detach

grommet from seat assembly and carefully remove evaporator and attached

components forward through seat assembly vertical wall relief. Cap fittings.

Installation

1. Remove caps. Position G784-1 evaporator assembly and associated components

in F377-1 middle seat assembly. Install screws securing evaporator and D799-7

(freeze) switch assembly to seat assembly. Install screws securing G798-1 cover

assembly to seat assembly.

2. Connect D795-8 line assembly and evaporator line b-nuts to G794 hose assemblies.

Using backup wrench, special torque hose b-nuts per Section 20-33, and torque

stripe per Figure 5-1.

3. Connect freeze switch wiring to airframe harness at connector and install ty-raps as

required. Cinch ty-raps until snug without over-tightening, and trim tips flush with

heads.

4. Perform leak detection per Section 12-83.

5. Charge system with refrigerant per Section 12-82.

6. Install screws securing F474-1 cover assembly and F380-8 angle to middle seat.

Attach F931-1 seat assembly (secured via hook and loop tape) to cover.

Page 21.8

Chapter 21 Environment Control

21-24 Troubleshooting

1. If air exiting overhead duct is not cold:

POSSIBLE CAUSE

TROUBLESHOOT/CORRECTIVE ACTION

Low Refrigerant

Recover refrigerant per Section 12-82. System should operate normally on

Charge/ Refrigerant

approximately 2.5 lb refrigerant.

Leak

If less than 2.5 refrigerant is recovered, perform leak detection per Section 12-83,

repair leaks if any, and charge system with refrigerant per Section 12-82.

Switch or Wiring

With aircraft not running, turn on Master switch and A/C switch on overhead duct

Problem Interrupting

(low or high setting ok). Have observer listen to and observe compressor clutch

Compressor Power

through cowl door. Clutch should engage (click and snap against pulley) whenever

A/C is switched on.

Check wiring at freeze switch (refer to Section 21-23), high and low pressure

switches (near compressor assembly), and full-down collective switch. Repair

any damaged wiring or connectors. Check continuity through each switch. All

switches should be closed with a properly charged system and aircraft at rest on

ground. Replace any defective switch.

Failed Compressor

Inspect belt.

V-Belt

Replace belt per Section 21-21 as required.

Insufficient

Inspect condenser installation. Verify no blockage and all seals in place.

Condenser Airflow

Remove blockage and/or repair seals to ensure airflow through core.

Extreme

Extreme temperature and humidity may result in cooling effect less than a typical

Environmental

automobile.

Conditions

No corrective action available.

2. If excessive condensation is found near evaporator assembly:

POSSIBLE CAUSE

TROUBLESHOOT/CORRECTIVE ACTION

Blocked or Kinked

Verify system is draining normally. After several minutes ground run in humid

Evaporator Drain

conditions with A/C on, water should be seen draining from the drain tube.

If water drainage is not observed, inspect drain line (refer to Section 5-45). Correct

any damaged or kinked lines. Clean sediment trap as required. Verify proper

function of check ball.

Extreme Humidity

Some condensation is unavoidable in extreme humidity.

Ensure all fresh air vents closed. Limit opening and closing cabin doors as much as

practical to limit humidity entering cabin.

Chapter 21 Environment Control

Page 21.9

21-30 Cabin Heat

21-31 Valve Assembly and Control Rigging

Refer to R66 Illustrated Parts Catalog (IPC) Figures 21-31 and 21-35.

A. Removal

1. Refer to Section 6-70. Remove hardware securing F794-1 and F794-2 (belly cover)

panels and remove panels. Remove engine cowling per Section 53-21.

2. Refer to Figure 21-3. Remove hardware securing A522-14 (heater valve) control

inner wire to G019-1 (heater) valve assembly arm.

3. Remove hardware securing AN742-3 clamps and control housing to F621-2 bracket.

4. Hinge aft right seat forward. Remove clamps, spacers, and hardware securing G391-2

and G391-5 line assemblies to aft right keel panel. Hinge seat back.

5. Loosen line assembly B-nuts from G400-2 muffler assembly & G396-1 union; disconnect

lines from valve assembly fittings and remove valve. Plug lines & cap fittings.

Installation

1. Refer to Figure 21-3. Remove caps and plugs, install G019-1 (heater) valve assembly

and connect G391-2 and G391-5 line assembly B-nuts to valve assembly fittings.

Hand-tighten B-nuts at valve assembly, G400-2 muffler assembly, and G396-1 union,

but do not torque.

2. Hinge aft right seat forward. Install clamps, spacers, and hardware securing line

assemblies to aft right keel panel. Verify security. Hinge seat back.

3. Position valve assembly so F621-2 bracket is vertical within 5°; special torque line

assembly B-nuts at valve assembly, muffler assembly, and union, and torque stripe

per Figure 5-1.

4. Perform control rigging per Part C, steps 3 thru 6.

5. Install engine cowling per Section 53-21.

C. Control Rigging

1. Refer to Section 6-70. Remove hardware securing F794-1 and F794-2 (belly cover)

panels and remove panels.

2. Refer to Figure 21-3. Remove palnut and loosen nut securing A462-4 fitting and

A522-14 (heater valve) control inner wire to G019-1 (heater) valve assembly arm.

3. As required, loosen hardware securing AN742-3 clamps and control housing to

F621-2 bracket. Position end of control housing flush-0.25 inch at or beyond edge

of aft clamp and install fasteners. Verify security.

4. Refer to detail in Figure 76-3. Push heater valve knob ON then pull up slightly to

create 0.03-0.10 inch clearance under knob. Position valve assembly arm in full

open detent. Verify sufficient inner wire beyond aft edge of fitting and special

torque fitting nut per Section 20-33.

5. Install fitting palnut, standard torque per Section 20-32, and torque stripe per Figure

5-1. Trim control wire 0.10-0.30 inch beyond aft edge of fitting.

6. Install (belly cover) panels, and install hardware. Verify security.

Chapter 21 Environment Control

Page 21.11

21-32 Muffler Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 21-35.

A. Removal

1. Refer to Section 6-70. Remove hardware securing F794-1 and F794-2 (belly cover)

panels and remove panels.

2. Refer to Figure 21-3. Loosen B277-12 clamp and pull A785-39 hose off of G400-2

muffler assembly. Install temporary covers on muffler and hose openings.

3. Loosen G391-4 line assembly B-nut at AN824-8D tee; disconnect G391-2 and -4

line assemblies from muffler.

4. Remove hardware securing MS21919WCH32 clamps and muffler to forward right

keel panel and remove muffler. Plug & cap fittings. As required, remove clamps

from muffler.

Installation

1. Refer to Figure 21-3. As required, install MS21919WCH32 clamps on G400-2

muffler assembly. Install hardware securing clamps and muffler to forward right keel

panel. Verify security.

2. Remove caps and plugs and connect G341-2 and G341-4 line assembly B-nuts

to muffler assembly fittings. Special torque B-nuts at AN824-8D tee and muffler

assembly, and torque stripe per Figure 5-1.

3. Remove temporary covers and slide B277-12 clamp and A785-39 hose onto muffler

assembly and tighten clamp. Verify security.

4. Install (belly cover) panels, and install hardware. Verify security.

21-33 Diffuser and Tee Assemblies

Refer to R66 Illustrated Parts Catalog (IPC) Figure 21-33.

A. Forward Diffuser and Tee Assembly Removal

1. Refer to Figure 21-3. Remove screws attaching upper console to lower console and

hinge console aft. Protect instrument face with foam support or equivalent.

2. Loosen two B277-24 clamps securing G400-1 tee assembly collars to G400-7 and

G400-8 diffuser assemblies. Slide diffusers outboard from tee and lower console

assembly.

3. Loosen B277-12 clamp securing A785-39 hose to tee assembly can weldment and

pull hose and clamp off of can.

4. Remove hardware securing MS21919WCH16 clamp and tee assembly to angle and

remove tee. As required, remove clamps from tee.

Page 21.12

Chapter 21 Environment Control

21-33 Diffuser and Tee Assemblies (continued)

Forward Diffuser and Tee Assembly Installation

1. Refer to Figure 21-3. As required, install MS21919WCH16 and (two) B277-24

clamps on G400-1 tee assembly. Install tee with clamps, and install hardware

securing MS21919WCH16 clamp and tee to angle.

2. Insert G400-7 and G400-8 diffuser assemblies through lower console and into tee

assembly. Orient diffuser holes vertically within 5°, and tighten clamps (against

spacers) securing tee assembly collars to diffusers. Verify security.

3. Slide A785-39 hose and B277-12 clamp onto tee assembly can weldment and tighten

clamp. Verify security.

4. Close and secure upper console.

C. Aft Diffuser Assemblies and Tee Removal

1. Refer to Section 6-70. Remove hardware securing F794-1 (belly cover) forward

panel and remove panel.

2. Refer to Figure 21-3. Hinge aft right and left seats forward. Remove hardware

securing G394-1 guards and G392-3 diffuser assemblies to aft seat assemblies and

remove guards. Hinge seats back.

3. Disconnect diffuser assembly B-nuts from AN824-8D tee and remove diffusers. As

required, disconnect G391-4 line assembly B-nut from tee and remove tee. Cap

fittings.

D. Aft Diffuser Assemblies and Tee Installation

1. Refer to Figure 21-3. As required, remove caps, install AN824-8D tee, and connect

G391-4 line assembly B-nut, but do not torque.

2. Remove caps and install G392-3 diffuser assemblies; connect diffuser assembly

B-nuts to tee, but do not torque. Hinge aft right and left seats forward and install

hardware securing diffusers to aft seat assemblies. Special torque line assembly and

diffuser B-nuts per Section 20-33, and torque stripe per Figure 5-1.

3. Install G394-1 guards and hardware securing guards to aft seat assemblies. Verify

security. Hinge seats back.

4. Install (belly cover) panel, and install hardware. Verify security.

Chapter 21 Environment Control

Page 21.13

CHAPTER 25

FURNISHINGS

Section

Title

Page

25-00

Description

25.1

25-10

Seat Harnesses

25.3

25-11

Seat Harness Removal

25.3

25-12

Seat Harness Installation

25.4

25-20

Seat Assemblies and Back Rests

25.5

25-21

Seat Assembly Removal and Installation

25.5

25-22

Back Rest Assembly Removal and Installation

25.5

25-23

Back Rest Cushion Replacement

25.5

25-30

Carpet

25.7

25-40

Insulation (Foam and Headliner)

25.8

25-50

General Maintenance

25.8

25-51

Pilot's Operating Handbook (POH) Strap Replacement . .

25.8

25-52

License Holder Replacement

25.9

25-53

Map Pocket Replacement

25.9

25-60

Emergency Equipment

25.10

25-61

Emergency Locator Transmitter (ELT)

25.10

25-62

Fire Extinguisher

25.11

Chapter 25 Furnishings

Page 25.i

CHAPTER 25

FURNISHINGS

25-00 Description

The seats are not adjustable but the pilot-side pedals are adjustable. Each helicopter is supplied

with a cushion which can be placed behind the pilot to position him forward. This allows

shorter pilots to reach the pedals, the cyclic stick in its most forward position, and the controls

on the center console.

Each seat is equipped with a combined seat belt and inertia reel shoulder strap. The inertia reel

is normally free but will lock if there is sudden movement as would occur in an accident.

Five-point harnesses are optional for the front seats. The five-point harness is equipped with

a webbing stop located above the inertia reel. The stop limits shoulder strap retraction and

should be adjusted so the straps are comfortable without excessive slack.

The main baggage compartment is located between the cabin and the engine compartment. It

is accessed via a large door on the aircraft right side. The cowl door annunciator illuminates

to warn the pilot when the door is not latched. A light illuminates the compartment when

the battery switch is ON. Tie down anchors are provided for securing items in the baggage

compartment. Observe placarded weight limits. Placard locations and illustrations are given

in Chapter 11.

Additional compartments are located under each seat except the center rear seat. Seat cushions

hinge forward for access to these compartments. Do not load these compartments above

the maximum fill lines. The lines indicate required crush space for the seats in an accident.

Baggage compartment dimensions are given in Chapter 6.

WARNING

Never repair or modify seat assemblies, including seat assembly

fabric, seat pans, or hook and loop tape (Velcro) securing fabric

to seat pans. Seat assembly energy-absorption design is critical

to occupant safety. To preserve crashworthiness, maintenance

is limited to seat assembly replacement.

Chapter 25 Furnishings

Page 25.1

25-10 Seat Harnesses

Refer to R66 Illustrated Parts Catalog (IPC) Figures 25-3 and 25-5. Refer to Figures 25-9, 25-

11, and 25-13 for optional Five-Point Harness Installation.

25-11 Seat Harness Removal

A. Forward Seat Harness (Standard)

1. Refer to Figure 25-1. Remove F680-1 and F680-3 collective cover assemblies; hinge

seat assemblies forward.

2. Remove hardware securing each F628-5 buckle assembly to inboard anchor, and

hardware securing each lap belt fitting to outboard anchor.

3. Remove shoulder strap guide covers and hardware securing guides to door frames.

4. Remove right side inertia reel cover and hardware securing reels to F369 and F370

forward seat backs. Remove seat harnesses.

Five-Point Harness (Optional, not shown; for forward seats only)

1. Remove screws securing F424-1 bumper assembly to F423-4 tube assembly and

remove bumper.

2. Refer to Figure 25-1. Remove F680-1 and F680-3 collective cover assemblies; hinge

seat assemblies forward.

3. Remove hardware securing lap belts to inboard and outboard anchors. Remove

hardware securing fifth-point belts to seat boxes.

4. Remove hole plugs, then remove inertia reel covers and hardware securing reels to

F369 and F370 forward seat backs. Remove five-point harnesses.

C. Aft Left and Right Seat Harness

1. Refer to Figure 25-1. Remove F931-1 seat assembly; hinge left and right seat

assemblies forward.

2. Remove hardware securing each F628-6 buckle assembly to inboard anchor, and

hardware securing each lap belt fitting to outboard anchor.

3. Remove shoulder strap guide covers and hardware securing guides to door frames.

4. Remove inertia reel covers and hardware securing reels to cabin bulkhead.

D. Center Seat Harness

1. Remove tailcone cowling per Section 53-23.

2. Refer to Figure 25-1. Remove F931-1 seat assembly; hinge left and right seat

assemblies forward.

3. Remove hardware securing F628-6 buckle assembly to inboard right side anchor and

hardware securing lap belt fitting to inboard left side anchor.

4. Remove shoulder strap guide cover and hardware securing guide to cabin bulkhead

and upper frame.

5. Remove F436-1 (headset jack) cover assembly and hardware securing inertia reel to

cabin bulkhead.

Chapter 25 Furnishings

Page 25.3

25-12 Seat Harness Installation

A. Forward Seat Harness (Standard)

1. Refer to Figure 25-1. Install hardware securing inertia reels to F369 and F370

forward seat backs. Install right side reel cover.

2. Install hardware securing shoulder strap guides to door frames. Standard torque

bolts per Section 20-32. Install guide covers.

3. Install hardware securing F628-5 buckle assemblies to inboard anchors, and lap belt

fittings to outboard anchors. Position buckle swage between two forward rivets.

Standard torque bolts per Section 20-32.

4. Install F680-1 and F680-3 collective cover assemblies.

Five-Point Harness (Optional, not shown; for forward seats only)

1. Attach inertia reels to F369 and F370 forward seat backs. Install covers and hole

plugs. Verify security.

2. Attach lap belt fittings to inboard and outboard anchors. Standard torque bolts per

Section 20-32.

3. Attach fifth point belts to seat boxes.

4. Refer to Figure 25-1. Install F680-1 and F680-3 collective cover assemblies; hinge

seat assemblies forward.

5. Position F424-1 bumper assembly on F423-4 tube assembly and install screws.

Verify security.

C. Aft Left and Right Seat Harness

1. Refer to Figure 25-1. Install hardware securing inertia reels to cabin bulkhead.

Install reel covers.

2. Install hardware securing shoulder strap guides to door frames. Standard torque

bolts per Section 20-32. Install guide covers.

3. Install hardware securing F628-6 buckle assemblies to inboard anchors, and lap belt

fittings to outboard anchors. Standard torque bolts per Section 20-32.

4. Install F931-1 seat assembly.

D. Center Seat Harness

1. Refer to Figure 25-1. Install hardware securing inertia reel to cabin bulkhead. Install

F436-1 (headset jack) cover assembly. Verify security.

2. Install hardware securing shoulder strap guide to cabin bulkhead and upper frame.

Standard torque bolt per Section 20-32. Install guide cover.

3. Install hardware securing F628-6 buckle assembly to inboard right side anchor, and lap

belt fitting to outboard left side anchor. Standard torque bolts per Section 20-32.

4. Install F931-1 seat assembly.

5. Install tailcone cowling per Section 53-23.

Page 25.4

Chapter 25 Furnishings

25-20 Seat Assemblies and Back Rests

Refer to R66 Illustrated Parts Catalog (IPC) Figure 25-1.

25-21 Seat Assembly Removal and Installation

WARNING

Never repair or modify seat assemblies, including seat assembly

fabric, seat pans, or hook and loop tape (Velcro) securing fabric

to seat pans. Seat assembly energy-absorption design is critical

to occupant safety. To preserve crashworthiness, maintenance

is limited to seat assembly replacement.

A. Seat Assembly

1. Refer to Figure 25-1. Remove or install hardware securing forward hinge to seat

box.

B. Center Seat Assembly

1. Refer to Figure 25-1. Center seat assembly attaches and detaches to and from the seat

box via hook and loop tape (Velcro).

25-22 Back Rest Assembly Removal and Installation

A. Aft Left and Right Back Rest Assembly

1. Refer to Figure 25-1. Remove or install hardware securing back rest assembly to

cabin bulkhead.

B. Center Back Rest Assembly

1. Refer to Figure 25-1. Detach back rest assembly hook and loop tape (Velcro) at

bottom; slide back rest assembly up and out of keyhole slots.

2. Install back rest assembly in keyhole slots and slide down. Press firmly on back rest

assembly hook and loop tape (Velcro) at bottom. Verify security.

25-23 Back Rest Cushion Replacement

A. Forward Back Rest

1. Refer to Figure 25-1. Drill out rivets securing back rest cushion to seat back panel

and deburr holes. Remove cushion.

2. Remove old adhesive residue from back rest support tube with plastic wedge. Wipe

surface with clean cloth, wet with acetone.

3. Center and straighten new cushion on seat back panel. Match drill seat back panel

#30 holes through cushion panel and deburr. Clean up debris.

4. Attach back rest cushion to seat back panel with rivets.

5. Apply B270-18 adhesive to underside of back rest cushion flap and to mating portion

of support tube. Pull flap around tube, smooth wrinkles, and trim excess flap.

Remove excess adhesive prior to curing.

Chapter 25 Furnishings

Page 25.5

25-23 Back Rest Cushion Replacement (continued)

B. Aft Left and Right Back Rest

1. Refer to Figure 25-1. Remove back rest assembly per Section 25-22.

2. Drill out rivets securing back rest cushion to seat back panel and deburr holes.

Remove cushion.

3. Center and straighten new cushion on seat back panel. Match drill seat back panel

#30 holes through cushion panel and deburr. Clean up debris.

4. Attach back rest cushion to seat back panel with rivets.

5. Install back rest assembly per Section 25-22.

25-30 Carpet

Refer to R66 Illustrated Parts Catalog (IPC) Figure 25-15.

A. Forward (Floor) Carpet Assembly Removal

1. Refer to Figure 25-2. Remove adjustable and/or removable pedals, as required.

2. Remove hardware securing scuff plates (and carpet) to cabin floor. Detach carpet from

floor via hook and loop tape (Velcro).

Forward (Floor) Carpet Assembly Installation

1. Refer to Figure 25-2. Attach carpet to floor via hook and loop tape (Velcro).

2. Install scuff plates; install B392-3 left-side cover (may be installed when pedals are

removed), as required.

3. Install adjustable and/or removable pedals, as required.

C. Aft (Floor) Carpet Assembly Removal and Installation

1. Refer to Figure 25-2. Attach or detach carpet to and from floor via hook and loop tape

(Velcro).

D. Carpet and Liner

CAUTION

Use caution when removing adhered carpet if carpet is intended

for reuse.

1. Removal

a. Starting at corners, gently peel back carpet by hand, or with plastic wedge or putty

knife.

b. Dampen old adhesive with Dupont Prep-Sol (or equivalent) to facilitate removal.

2. Installation

a. Verify proper carpet fit. Trim as required (do not trim carpet welt).

b. Apply B270-8 adhesive to bonding surface and carpet backing. Press carpet to

surface, smooth wrinkles, and remove excess adhesive prior to curing.

Chapter 25 Furnishings

Page 25.7

25-40 Insulation (Foam and Headliner)

Refer to R66 Illustrated Parts Catalog (IPC) Figure 25-17.

A. Removal

NOTE

Use caution not to damage surface underneath insulation when

removing insulation with tools.

NOTE

Insulation is installed using adhesive, except under seat

assemblies. Order new insulation as required; reuse of removed

insulation is not recommended.

1. Peel off insulation by hand.

2. Using plastic wedge or putty knife, carefully remove residual insulation

and

old

adhesive.

3. Wipe bonding surface with clean cloth, wet with acetone.

Installation

1. Verify proper insulation fit. Trim as required.

2. Apply B270-8 adhesive to bonding surface and insulation backing. Press insulation to

surface, smooth wrinkles, and remove excess adhesive prior to curing.

25-50 General Maintenance

25-51 Pilot's Operating Handbook (POH) Strap Replacement

Refer to R66 Illustrated Parts Catalog (IPC) Figure 25-19.

A. Removal

1. Remove POH.

2. Drill out rivets securing POH retaining strap to cabin right side and remove strap.

Deburr holes and clean up debris.

B. Installation

1. Cleco POH retaining strap to cabin right side holes. Remove clecos and install rivets.

Verify security.

2. Install POH.

Page 25.8

Chapter 25 Furnishings

25-52 License Holder Replacement

Refer to R66 Illustrated Parts Catalog (IPC) Figure 25-11.

A. Removal

1. Remove aircraft documents from license holder.

2. Drill out rivets securing license holder to cabin under left side windshield frame and

remove license holder. Deburr holes and clean up debris.

B. Installation

1. Cleco license holder to cabin holes under left side windshield frame. Remove clecos

and install rivets. Verify security.

2. Insert aircraft documents into holder and tuck upper flap into frame.

25-53 Map Pocket Replacement

Refer to R66 Illustrated Parts Catalog (IPC) Figure 25-11.

A. Removal

1. Drill out rivets securing map pocket to front wall of forward seat box. Remove

pocket, washers, and retaining strips. Deburr holes and clean up debris.

B. Installation

1. Fold (long) outboard pocket edge around (long) A913-1 strip, align holes, and align

holes with front of forward seat box. Cleco in place.

2. Pull material taut, fold (short) inboard pocket edge around (short) A913-2 strip, align

holes, and align holes with front of forward seat box. Cleco in place. Trim excess

material.

3. Remove clecos and install washers and rivets.

25 OCT 2010

Chapter 25 Furnishings

Page 25.9

25-60 Emergency Equipment

25-61 Emergency Locator Transmitter (ELT)

NOTE

ELT installation is optional equipment.

A. ELT Information and Programming

Refer to Section 96-90 for ELT system description. Refer to Section 5-20 for scheduled

maintenance.

Refer to ELT Kannad 406 AF-Compact/406 AF-Compact (ER) Installation and Operation

Manual for maintenance requirements and procedures. Additional ELT information is

available on the RHC website at: http://www.robinsonhelicopter.com/supportelt.htm.

aircraft ownership, or tail number changes. For registration information, visit the

COSPAS-SARSAT website at: http://cospas-sarsat.org.

Kannad 406 AF-Compact ELTs are interchangeable between aircraft. A dongle contains

a memory chip that must be programmed with aircraft-specific information prior to

installation for the ELT to function. The dongle may be removed and shipped to RHC or

a Kannad service center for reprogramming.

Transmitter Removal and Installation

The ELT activates when subjected to a significant change in velocity (as in an accident),

by remote control switch located on the cyclic control panel, or by a switch on the ELT

transmitter.

NOTE

Do not cut B359-2 releasable, reusable ty-rap.

1. To remove ELT transmitter:

a. Follow instructions hot stamped on ty-rap: "PULL RED TAB TO REMOVE."

b. Release Velcro strap and remove transmitter. Disconnect dongle & antenna lead.

2. To install ELT transmitter:

a. Connect dongle and antenna lead and install transmitter. Secure Velcro strap and

install B359-2 ty-rap.

C. Dongle Removal and Installation

1. Cut and discard ty-raps as required, disconnect dongle from plastic connector and

ELT transmitter, and remove dongle.

2. Connect programmed dongle to plastic connector and ELT transmitter, and install

ty-raps as required. Cinch ty-raps until snug without over-tightening, and trim tips

flush with heads.

Page 25.10

Chapter 25 Furnishings

25 OCT 2010

25-62 Fire Extinguisher

Refer to R66 Illustrated Parts Catalog (IPC) Figure 25-13.

NOTE

Fire extinguisher installation is optional equipment.

A. Inspection

Inspect fire extinguisher monthly according to manufacturer's instructions. Maintenance

instructions are located on extinguisher bottle. Record inspection date and findings as

required.

Bracket Removal

1. Unlock fire extinguisher bracket and remove extinguisher.

2. Remove hardware securing bracket to cabin under left side windshield frame and

remove bracket.

C. Bracket Installation

1. Install hardware securing fire extinguisher bracket to cabin under left side windshield

frame. Select screw length as required to provide 0.00-0.06 inch thread exposure.

Verify security.

2. Inspect fire extinguisher per Part A.

3. Install fire extinguisher and lock extinguisher bracket.

25 OCT 2010

Chapter 25 Furnishings

Page 25.11

CHAPTER 28

FUEL SYSTEM

28-00 Description

This chapter includes instructions for the removal and installation of the airframe fuel system

components. Refer to RR300 Series Operation and Maintenance Manual (OMM) for engine fuel

system maintenance procedures.

A single bladder-type crash-resistant fuel cell supplies fuel via gravity flow to the engine. The

fuel cell incorporates left and right vent fittings, a filler port, a fuel gage sender, a low-fuel

switch assembly, a sump drain, and a finger strainer at the fuel outlet. The low-fuel switch

assembly activates the low fuel segment on the annunciator panel, indicating approximately

five gallons of usable fuel remaining. The vent fittings each have a roll-over valve to prevent

fuel leakage in any attitude.

The fuel cell is secured inside an aluminum structure. The filler cap is located under a cowl

door. The left and right side vent fittings are interconnected vent through two risers within the

mast fairing. A fuel valve is located on the forward side of the firewall and is controlled by a

push-pull cable control at the base of the collective stick.

The engine incorporates a fuel pump assembly with an inlet filter. A differential pressure

switch illuminates the fuel filter warning light if the filter becomes contaminated.

A single drain allows fuel sampling from the low point in the fuel cell. The drain tube is

accessible via a left side cowl door. The drain is opened by extending the plastic tube clear of

the aircraft and pushing up on the drain.

FIGURE 28-1 FUEL SYSTEM OVERVIEW

25 OCT 2010

Chapter 28 Fuel System

Page 28.1

28-10 Bladder Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figures 28-1 and 28-3.

CAUTION

G028-1 bladder assembly temperature should be above 65°F

before removing, installing, or flexing bladder.

A. Removal

Defuel helicopter per Section 12-42.

Remove tailcone cowling assembly per Section 53-23.

Remove fuel quantity sender per Section 28-21.

Refer to Figure 28-2. Cut and discard safety wire securing A729-40 tube to left roll-

over vent valve and pull tube off vent valve. Remove fasteners securing F250-1 cover

assembly to G028-1 bladder assembly and F028-1 support assembly and remove cover.

Remove and discard o-ring.

Cut and discard safety wire securing A729-2 tube to right roll-over vent valve and pull

tube off vent valve. Remove screws and washers securing valve to support. Cut and

discard ty-rap securing 35486 hanger tab to G915-5 tab.

Remove low-fuel switch assembly per Section 28-22. Tape bladder openings.

Disconnect D205-21 (fuel outlet) hose assembly from B254-3 strainer and cap fittings.

Remove screws and washers securing strainer to support. Remove strainer and tape

bladder opening.

Remove sump valve per Section 28-12.

Remove hardware securing G004-4 (right side, aft fuselage) skin to cabin and remove

skin. Detach bladder hook tape from support loop tape, and remove bladder through

right side opening.

25 OCT 2010

Chapter 28 Fuel System

Page 28.3

28-10 Fuel Bladder (continued)

Installation

Refer to Figure 28-2. Dust exterior of G028-1 bladder assembly and F028-1 support

assembly floor with talcum powder to facilitate bladder slippage along metal surface.

Do not allow powder to enter bladder.

Note locations of hook and loop tape on bladder lower surface and support floor. Orient

bladder, fold into thirds, place in center of support, and unfold into position.

Install screws and washers securing right roll-over vent valve to support. Fit A729-

2 tube onto vent valve; wrap tube with two turns 0.032-inch diameter lockwire and

safety tube to vent valve.

Install MS3367-7-9 ty-rap securing 35486 hanger tab to G915-5 tab. Cinch ty-rap until

snug without over-tightening, and trim tip flush with head.

NOTE

Verify bladder is free of wrinkles across lower surface and

properly located before attaching hook and loop tape. Bladder

may be pressurized with air to 1 psi max to assist installation.

CAUTION

Avoid contaminating bladder assembly interior. Cover arms with

sleeves and use lint-free gloves when working inside bladder.

Remove tape from bladder assembly openings. Insert a clean, smooth, blunt wooden

dowel through bladder service opening and press on bladder lower surface to attach

hook and loop tape. Verify security.

Install low-fuel switch assembly per Section 28-22.

Install screws and washers securing bladder outlet to support. Lubricate new MS29512-

06 packing using A257-6 grease and install on B254-3 strainer. Install strainer in

bladder and special torque strainer per Section 20-33.

Remove caps and connect D205-21 hose assembly to strainer. Special torque B-nut per

Section 20-33 and torque stripe per Figure 5-1.

Install sump valve per Section 28-12.

10.

Lubricate new MS29513-270 packing using A257-6 grease and position within recess

around bladder service opening. Install F250-1 cover assembly and install hardware

securing cover to bladder and support. Verify security. Fit A729-40 tube onto left

roll-over vent valve; wrap tube with two turns 0.032-inch diameter lockwire and safety

tube to vent valve.

11.

Install fuel quantity sender per Section 28-21.

12.

Service helicopter with two gallons of fuel per Section 12-41. Verify no leaks, especially

at bladder outlets. Install G004-4 (right side, aft fuselage) skin and install hardware

securing skin to cabin. Verify security.

13.

Perform fuel flow check per Section 28-40.

14.

Install tailcone cowling assembly per Section 53-23.

25 OCT 2010

Chapter 28 Fuel System

Page 28.5

28-11 Roll-Over Vent Valves

Refer to R66 Illustrated Parts Catalog (IPC) Figure 28-1.

WARNING

R66 roll-over vent valves contain two anodized aluminum balls,

the orientation of which are critical to vent valve function. The

blue hollow ball on top floats and seals the vent in the event of

inadvertent over-filling or in-flight sloshing. The red solid ball on

the bottom presses the hollow ball against the vent seat if the

aircraft is inverted. Valve maintenance is limited to replacing

internal packings.

A. O-ring Replacement

1. Remove tailcone cowling assembly per Section 53-23, as required.

2. Refer to Figure 28-2. Cut and discard safety wire securing A729 tube to roll-over

vent valve and pull tube off valve.

3. Remove G254-2 fitting or G254-6 retainer. Remove and discard MS29512-10

packing (G254-2 fitting only) and A215-015 o-ring.

4. Install new A215-015 o-ring in groove inside fitting or retainer. Lubricate new

MS29512-10 packing with A257-6 grease and install over G254-2 fitting threads.

5. Install fitting or retainer and special torque per Section 20-33.

6. Fit A729 tube onto roll-over vent valve; wrap tube with two turns 0.032-inch diameter

lockwire and safety tube to vent valve.

7. Install tailcone cowling assembly per Section 53-23, as required.

28-12 Sump Valve

Refer to R66 Illustrated Parts Catalog (IPC) Figure 28-3.

A. Removal

1. Defuel helicopter per Section 12-42.

2. Refer to Figure 28-2. Cut and discard safety wire securing A729-43 tube to 1250H

(sump) valve and remove tube.

3. Remove valve from G154-1 outlet assembly; tape bladder opening.

4. Actuate and lock valve to expose stem; remove and discard o-ring.

Page 28.6

Chapter 28 Fuel System

25 OCT 2010

28-12 Sump Valve (continued)

B. Installation

1. Refer to Figure 28-2. Actuate and lock 1250H (sump) valve to expose stem; install

new o-ring in stem seat.

2. Lightly coat valve threads with B270-6 sealant. Remove tape and install valve in

G154-1 outlet assembly: standard torque valve per Section 20-32 and torque stripe

per Figure 5-1.

3. Fit A729-43 tube onto valve; wrap tube with two turns 0.032-inch diameter lockwire

and safety tube to valve.

28-20 Fuel Quantity

28-21 Fuel Quantity Sender

Refer to R66 Illustrated Parts Catalog (IPC) Figure 28-1.

CAUTION

Avoid contaminating bladder interior. Cover arms with sleeves

and use lint-free gloves when working inside bladder.

A. Removal

1. Turn BATTERY switch OFF; pull GAGES circuit breaker. Open fueling cowl door.

2. Refer to Figure 28-2. Remove hardware securing G271-1 guard to F250-1 cover

assembly and remove guard.

3. Remove hardware securing F049-04 (fuel quantity sender) electrical harness wiring

to F550-1 sender.

4. Remove hardware securing sender to cover assembly. Carefully pull sender lever

through cover assembly opening. Tape bladder opening, and close fueling cowl

door.

B. Installation

1. Turn BATTERY switch OFF; pull GAGES circuit breaker. Open fueling cowl door.

2. Refer to Figure 28-2. Remove tape and install F550-1 fuel quantity sender and

15-423 gasket (supplied with new sender) in F250-1 cover assembly by carefully

lowering sender lever through opening.

3. Install hardware securing sender to cover. Special torque bolts in criss-cross pattern

per Section 20-33, and torque stripe per Figure 5-1.

4. Install F049-04 (fuel quantity sender) electrical harness wiring on sender studs, install

nuts, and special torque per Section 20-33. Install (different size) palnuts, special

torque per Section 20-32, and torque stripe per Figure 5-1.

5. Calibrate fuel quantity sender per Part C.

25 OCT 2010

Chapter 28 Fuel System

Page 28.7

28-21 Fuel Quantity Sender (continued)

C. Calibration

1. Defuel helicopter per Section 12-42.

2. Pull fuel valve knob OFF. Service helicopter with 19.4 gallons of fuel per Section

12-41.

3. Push in GAGES circuit breaker, turn BATTERY switch ON, and read fuel quantity

gage. Verify gage reads one-half needle width to one & one-half needle widths

below one-quarter mark. If fuel gage indication is correct, proceed to step 5.

4. If fuel gage indication is incorrect, remove fuel quantity sender per Part A. Slightly

bend sender lever up for a gage that reads too high, or down for a gage that reads

too low. Install fuel quantity sender per Part B.

5. Turn BATTERY switch OFF; push fuel valve knob ON.

6. Install G271-1 guard and hardware securing guard to F250-1 cover assembly. Verify

security. Close fueling cowl door.

28-22 Low-Fuel Switch Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 28-3.

NOTE

As required, remove fuel quantity sender per Section 28-21 and

F250-1 cover assembly per Section 28-10, to facilitate A521-2

low-fuel switch assembly removal/installation.

CAUTION

Avoid contaminating bladder interior. Cover arms with sleeves

and use lint-free gloves when working inside bladder.

A. Removal

1. Defuel helicopter per Section 12-42.

2. Refer to Section 6-70. Open baggage compartment door. Remove hardware securing

G248-1 (baggage compartment) cover and remove cover.

3. Refer to Figure 28-2. As required, cut and discard safety wire securing A729-55

tube to G930-1 (low-fuel switch) drain assembly. Remove screws securing G930-4

retainer and drain assembly to G250-1 sump tray.

4. Open fueling cowl door and remove fuel cap. Carefully capture A521-2 switch

assembly body with clean mechanical fingers (avoid capturing movable float).

5. Inside baggage compartment, remove nut, washer assembly, and spacer securing

A521-2 switch assembly to tray. Disconnect F049-03 (GCU) electrical harness

wiring from switch assembly wiring at connectors.

6. Carefully pull switch assembly through fuel cap opening (avoid F550-1 [fuel quantity]

sender). Install fuel cap, and close fueling cowl door.

Page 28.8

Chapter 28 Fuel System

25 OCT 2010

28-22 Low-Fuel Switch Assembly (continued)

B. Installation

1. Install new MS29512-05 packing over switch assembly threads.

2. Refer to Figure 28-2. Remove fuel cap. Tape switch assembly wiring to 4-ft length

of lockwire; insert other end of wire through fuel cap opening and through switch

assembly opening. Carefully grip switch assembly body with mechanical fingers and

lower switch assembly to bottom of bladder. Inside baggage compartment, guide

wiring through opening, install spacer, washer assembly, and nut securing switch

assembly to G250-1 sump tray, and special torque nut per Section 20-33. Remove

tape and lockwire. Release and remove mechanical fingers, and install fuel cap.

3. Connect F049-03 (GCU) electrical harness wiring to switch assembly wiring at

connectors. Fit wiring through gap in G930-1 (low-fuel switch) drain assembly seal,

install G930-4 retainer, and install screws securing retainer and drain assembly to

tray. Verify security. Seal gap in drain assembly seal where wires pass thru using

B270-5 sealant.

4. If removed, fit A729-55 tube onto drain assembly; wrap tube with two turns 0.032-

inch diameter lockwire and safety tube to drain assembly.

5. Service helicopter with seven gallons of fuel per Section 12-41. Verify no leaks

around switch assembly mount. Open sump drain access door and verify no leaks

from (low-fuel switch) drain tube. Perform operation check per Part C.

6. Refer to Section 6-70. Install G248-1 (baggage compartment) cover and install

hardware. Verify security. Close and latch baggage compartment door.

C. Operation Check

1. Turn BATTERY switch ON.

2. Open fueling cowl door and remove fuel cap.

3. Drain fuel until float drops, or insert a clean, non-sparking rod through fuel cap

opening and gently depress A521-2 (low-fuel) switch assembly float; verify LOW

FUEL annunciator segment illuminates.

4. Remove rod, install fuel cap, and close cowl door.

5. Turn BATTERY switch OFF.

25 OCT 2010

Chapter 28 Fuel System

Page 28.9

28-30 Fuel Valve

Refer to R66 Illustrated Parts Catalog (IPC) Figure 28-5.

A. Removal

1. Defuel helicopter per Section 12-42.

2. Refer to Figures 28-2 and 28-4. Open sump drain access door. Remove palnut and

loosen nut securing A462-4 fitting and A522-11 (fuel valve) control inner wire to F670-

1 fuel valve arm.

3. Disconnect D205-21 and B283-12 hose assemblies from fuel valve and cap fittings.

4. Remove screws and washers securing fuel valve to F233-1 firewall and remove fuel

valve through sump drain access door.

Installation

1. Refer to Figures 28-2 and 28-4. Install F670-1 fuel valve and install screws and washers

securing valve to F233-1 firewall. Verify security.

2. Remove caps and connect D205-21 and B283-12 hose assemblies to fuel valve. Special

torque B-nuts per Section 20-33 and torque stripe per Figure 5-1.

3. Perform fuel valve control rigging per Section 28-31.

4. Perform fuel flow check per Section 28-40.

28-31 Fuel Valve Control Rigging

Refer to R66 Illustrated Parts Catalog (IPC) Figure 28-5.

1. Refer to Figures 28-2 and 28-4. Open sump drain access door. Remove palnut and

loosen nut securing A462-4 fitting and A522-11 (fuel valve) control inner wire to F670-

1 fuel valve arm.

2. Open baggage compartment door. As required, loosen hardware securing AN742-

3 clamps and control housing to G915-3 bracket. Position end of control housing

flush-0.25 inch at or beyond edge of outboard clamp and install fasteners. Verify

security.

3. Refer to detail in Figure 76-3. Push fuel valve knob ON then pull up slightly to create

0.03-0.10 clearance under knob. Position fuel valve arm in full open detent. Verify

sufficient inner wire beyond outboard edge of fitting and special torque fitting nut per

Section 20-33.

4. Pull fuel valve knob OFF and verify valve arm fully contacts OFF detent. Push fuel

valve knob ON and verify valve arm fully contacts ON detent, and meets clearance

requirement. Reposition fitting per previous steps, as required.

5. Install fitting palnut, standard torque per Section 20-32, and torque stripe per Figure

5-1. Trim control wire 0.10-0.30 inch beyond aft edge of fitting.

6. Close sump drain access door. Close and latch baggage compartment door.

25 OCT 2010

Chapter 28 Fuel System

Page 28.11

28-40 Fuel Flow Check

1. Open mast fairing per Section 53-22. Remove engine cowling per Section 53-21.

2. Refer to Figure 28-2. Attach a temporary hose to one of the vent weldment openings. With

the fuel cap installed, blow into the hose (do not use compressed air) and verify air blows

out the other vent opening. If air does not blow out the other vent, remove obstruction(s)

in vent line(s) or in fuel bladder and repeat check.

3. Defuel helicopter per Section 12-42, then service helicopter with 19.4 gallons of fuel per

Section 12-41.

4. Weigh a suitable, empty container having a volume of at least one gallon. Record weight

of empty container in table below.

5. Pull fuel valve OFF and disconnect B283-12 hose assembly from the engine fuel inlet

fitting.

6. Using a second, suitable container, push fuel valve ON and drain fuel into second container

for a few seconds to purge system of air. Then fill the weighed container for 60 seconds.

Weigh and record weight of empty container & 60 seconds of fuel flow in table below.

7. Perform the following calculation:

Combined weight of empty container & 60 seconds fuel flow:

—

Subtract Weight of empty container:

Equals Weight of 60 seconds fuel:

8. Minimum fuel flow (at 19.4 gallons of fuel) is 4.75 lb/min (60 seconds). If fuel flow is less

than 4.75 lb/min, remove obstruction(s) in vent line(s), fuel bladder, fuel hoses, fuel valve,

or fuel strainer (inside bladder at outlet), and repeat check until fuel flow is satisfactory.

9. Close mast fairing per Section 53-22. Install engine cowling per Section 53-21.

Page 28.12

Chapter 28 Fuel System

25 OCT 2010

CHAPTER 32

LANDING GEAR

32-00 Description

A spring and yield skid type landing gear is used. Most hard landings will be absorbed

elastically. However, in an extremely hard landing, the struts will hinge up and outward as the

center crosstube yields (takes permanent set) to absorb the impact. Slight yielding of the aft

crosstube is acceptable. For tail skid height limitation, see Section 32-20. For hard landing

inspection, see Section 5-65.

Hardened steel wear shoes are mounted on the bottom of the skids. Inspect skid tubes and

skid shoes per Section 32-30, particularly if autorotation landings with ground contact have

been performed.

Pop-out float landing gear is available as optional equipment. See Section 32-60 for pop-out

float installation description.

32-10 Landing Gear Assembly

A. Removal

Open cabin aft doors and baggage compartment door. Remove engine cowling per

Section 53-21.

Refer to Section 6-70; remove G308-2 and two F475-6 cross tube covers. Remove

fairing assemblies per Section 32-40.

Refer to Figure 32-1. Remove hardware securing A936-3 (ground) wire assembly to

aft, right landing gear attachment.

Using putty knife or plastic scraper, cut sealant securing four cross tube rain caps to

landing gear assembly and remove caps. Remove sealant residue from caps, cross

tubes, and strut assemblies. Clean surfaces with solvent.

Hoist helicopter per Section 7-20. Raise skids above ground approximately one foot.

CAUTION

Support landing gear assembly as mounting bolts are removed.

Do not damage forward cross tube hinged inspection cover.

Remove hardware securing forward, right strut assembly & forward cross tube to fuselage

support. Mounting bolt access hole is located on aft, right seat box forward wall.

Remove hardware securing aft, right strut assembly & aft cross tube to fuselage support.

Mounting bolt access hole is located on baggage compartment aft wall.

Rotate forward, left shackle to align mounting bolt with access hole on aft, left seat box

forward wall. Remove hardware securing landing gear to shackle.

If air conditioning is installed, remove hardware securing G787-3 and G787-4 brackets

to condenser support and remove brackets.

10.

Remove nut, washer, and spacer from aft, left mounting bolt (bolt stays in place). Carefully

lower forward crosstube below belly, then move assembly aft, off of aft left bolt.

Chapter 32 Landing Gear

Page 32.1

32-10 Landing Gear Assembly (continued)

Installation

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-1.

WARNING

Landing gear mounting bolts are critical fasteners. See Section

20-30 for torque requirements.

CAUTION

Support landing gear assembly as mounting bolts are installed.

Do not damage forward cross tube hinged inspection cover.

Hoist helicopter per Section 7-20 to required height.

Refer to Figure 32-1. Align mounting bolt (in place) with aft, left landing gear attachment.

Install hardware, special torque fastener per Section 20-33, & torque stripe per Figure

5-1. If air conditioning is installed, install hardware securing G787-3 and G787-4

brackets to condenser support. Verify security.

Insert hardware thru access hole on aft, left seat box forward wall, and thru shackle.

Align mounting bolt with forward, left landing gear attachment. Install hardware, special

torque bolt per Section 20-33, & torque stripe per Figure 5-1.

Insert hardware thru right side access hole on baggage compartment aft wall and aft,

right landing gear attachment. Install hardware, special torque bolt per Section 20-33,

& torque stripe per Figure 5-1.

Insert hardware thru access hole on aft, right seat box forward wall and forward, right

landing gear attachment. Install hardware, special torque bolt per Section 20-33, &

torque stripe per Figure 5-1.

Lower helicopter per Section 7-20. Close cabin aft doors and baggage compartment

door.

Verify surface under terminal is clean and dry and install hardware securing A936-3

(ground) wire assembly to aft, right landing gear attachment. Standard torque screw

per Section 20-32 and torque stripe per Figure 5-1.

Verify rain caps and bonding surfaces are clean and dry. Bond caps to landing gear

assembly using B270-1 sealant. Mix sealant according to manufacturer's instructions.

Refinish landing gear as required per Chapter 20.

10.

When surfaces are dry, install engine cowling per Section 53-21. Refer to Section 6-70;

install G308-2 and two F475-6 cross tube covers. Install fairing assemblies per Section

32-40.

Chapter 32 Landing Gear

Page 32.3

32-20 Cross Tubes

A. Inspection

For helicopters with F014-1 (standard) landing gear or F014-4 (pop-out float) landing gear,

replace aft cross tube if tail skid height is less than 38 inches from ground when aircraft is

minimally loaded on level pavement.

For helicopters with F014-5 (extended) landing gear, replace aft cross tube if tail skid height

is less than 30 inches from ground when aircraft is minimally loaded on level pavement.

For hard landing inspection, see Section 5-65.

Removal

1. Remove landing gear per Section 32-10.

2. Refer to Figure 32-2. Remove hardware securing one skid tube (left or right) to same

side strut assemblies.

3. Remove hardware securing cross tube (to be replaced) to strut assemblies. Using brass

drift, tap on strut assembly collars to separate struts from cross tube. Do not tap on

jack tabs.

C. Installation

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-1.

NOTE

When installing A936-3 (ground) wire assembly, verify finish is

removed from surface under wire terminal.

1. Refer to Figure 32-2. Lightly coat mating surfaces of cross tube with zinc-chromate or

epoxy primer using approved materials per Section 20-70. While primer is wet, install

cross tube into strut assemblies and align fastener holes.

2. Install hardware securing cross tube to strut assemblies, standard torque screws per

Section 20-32, and torque stripe per Figure 5-1.

3. Install hardware securing left or right skid tube to strut assemblies, standard torque

bolts per Section 20-32, and torque stripe per Figure 5-1.

4. Install landing gear per Section 32-10.

Chapter 32 Landing Gear

Page 32.5

32-30 Skid Tubes

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-1.

CAUTION

Minimize personnel movement around raised helicopter. Use

caution when working under raised skid tubes.

A. Inspection

1. Install ground handling wheels per Section 9-11.

2. Pull down on tail rotor gearbox and place blocks under skid tubes, forward of forward

strut assemblies. Skids should be approximately parallel with the ground.

3. Measure damage on left or right skid tube. Replace skid tube if damage exceeds the

following limits:

0.030 inch maximum depth longitudinal scratch (no length limit).

0.030 inch maximum depth and 0.50 inch maximum length circumference scratch.

0.500 inch maximum width flat spot.

4. Measure the thickness of skid tube's skid shoes (five per skid). Replace a skid shoe

per Section 32-31 if damage exceeds 0.050 inch minimum thickness. Repeat steps on

opposite skid tube.

Removal

1. Jack or hoist helicopter per Sections 7-10 or 7-20. Raise skids above ground approximately

4 inches.

2. Refer to Figure 32-3. Remove hardware securing left or right skid tube to same side

strut assemblies.

C. Installation

1. Jack or hoist helicopter per Sections 7-10 or 7-20 to required height.

2. Refer to Figure 32-3. Install hardware securing skid tube to strut assemblies. Standard

torque bolts per Section 20-32 and torque stripe per Figure 5-1.

3. Lower helicopter per Sections 7-10 or 7-20.

Chapter 32 Landing Gear

Page 32.7

32-31 Skid Shoes

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-1.

A. Inspection

Inspect skid tubes and skid shoes per Section 32-30.

B. Replacement

1. Refer to Figure 32-3. Remove and discard hardware securing skid shoe to skid tube.

Discard a shoe damaged beyond limits in Section 32-30.

2. Install new A142-1 screws to secure skid shoe to skid tube. Standard torque screws

per Section 20-32.

32-32 Skid Extension Replacement

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-1.

1. Remove skid tube per Section 32-30.

2. Refer to Figure 32-3. Remove and discard hardware securing aft skid shoe to skid tube.

Remove skid extension.

3. Clean interior of skid tube as practical. Install new skid extension and align fastener

holes.

4. Install new A142-1 screws to secure aft skid shoe to skid tube. Standard torque screws

per Section 20-32.

5. Install skid tube per Section 32-30.

6. Fill gap in side of skid extension using B270-1 sealant. Mix sealant according to

manufacturer's instructions.

32-33 Ground Handling Wheel Support Replacement

Refer to R66 Illustrated Parts Catalog (IPC) 32-1.

1. Refer to Figure 32-3. Remove hardware securing support weldment to skid tube and

remove support.

2. Install hardware securing new support weldment to skid tube. Verify correct support

orientation. Special torque hardware per Section 20-33 and torque stripe per Figure 5-1.

Page 32.8

Chapter 32 Landing Gear

32-40 Fairing Assemblies

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-5.

A. Removal

1. Refer to Figure 32-3. Remove screws securing fairing assembly together at trailing

edge.

2. Remove screws securing fairing assembly to strut assembly. Unscrew clamp through

fairing inboard access hole and remove fairing.

B. Installation

1. Refer to Figure 32-3. Verify fairing assembly clip nuts are installed. Verify clamp

threads through fairing clips, with hex facing inboard access hole.

2. Position fairing assembly on strut assembly and install screws securing fairing to strut.

3. Tighten clamp, and special torque hex through fairing assembly inboard access hole per

Section 20-33.

4. Install screws securing fairing assembly together at trailing edge.

5. Verify 0.20-0.30 inch clearance between fairing assembly edge and fuselage. Remove

and trim fairing as required; reinstall per preceding steps.

32-50 Maintenance

1. Refer to Figure 32-3. Verify drain holes in bottom of skid tubes are free of obstructions

(two per skid, between two forward skid shoes and aft of skid shoe at forward strut

assembly).

2. Refinish landing gear to prevent corrosion per Chapter 20.

3. Inspect skid tubes and skid shoes per Section 32-30, especially following touch-down

autorotations or running take-offs or landings.

4. Verify skid tube and strut assembly rain caps are properly sealed. Replace or re-seal rain

caps per the following:

a. Using putty knife or plastic scraper, cut sealant securing rain cap to landing gear

assembly and remove cap. Remove sealant residue from caps, cross tubes, and/or strut

assemblies. Clean surfaces with solvent.

b. Verify rain caps and bonding surfaces are clean and dry. Bond caps to landing gear

assembly using B270-1 sealant. Mix sealant according to manufacturer's instructions.

Chapter 32 Landing Gear

Page 32.9

32-60 Pop-Out Floats Installation

Pop-out floats are optional equipment for R66 helicopters. The pop-out float installation

includes inflatable floats stowed in protective covers secured to the skid tubes, a pressure

cylinder located in the compartment beneath the right aft seat, an inflation manifold, an inflation

lever located on the pilot’s collective stick, and a modified aux stabilizer.

The valve located on top of the pressure cylinder has a pressure gage, a thermal relief valve

which releases pressure if exposed to excessive heat (281º F), a metal sealing disk, and a

spring-loaded pin.

The red inflation lever on the pilot’s collective stick is equipped with a spring-loaded safety to

prevent inadvertent float inflation. To inflate the floats, the safety is pushed in and rotated

from LOCKED to READY position, then the inflation lever is squeezed with enough force to

shear the aluminum rivet. The spring-loaded pin in the pressure cylinder valve punctures the

metal sealing disk, and 4945 psig (nominal, at 20º C) of helium is released into the inflation

manifold to inflate both floats.

The manifold consists of hoses, fittings, and a check valve at each of the six float chambers

(per float). Each float chamber has a topping valve for manual inflation, and a pressure relief

valve to vent excess internal pressure.

A modified aux stabilizer improves controllability at high airspeeds with floats inflated.

32-61 Cylinder Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-7.

NOTE

Cylinders are discharged during float inflation check every 3

years. Cylinder hydrostatic test is required every

5 years.

Cylinder life-limit is 15 years from date of manufacture. To

ensure cylinder limitations are not overflown, returning to

service cylinders with more than 2 years since hydrostatic test

or 12 years since date of manufacture is not recommended.

WARNING

D679 Cylinder contents are under extreme pressure. Install

MT545-1 pin assembly in D757-1 valve assembly during

maintenance to prevent cylinder discharge.

Chapter 32 Landing Gear

Page 32.11

32-61 Cylinder Assembly (continued)

A. Removal

1. Refer to Figure 32-5. Hinge right aft seat assembly forward. Install MT545-1 pin

assembly in D757-1 valve assembly.

2. Disconnect D674-9 hose assembly from valve fitting. Install MT546-1 diffuser on

valve fitting and special torque diffuser to 120 in.-lb. Cap hose to prevent foreign

object contamination.

3. Remove hardware securing D761-2 cover to valve and D761-1 support. Remove

cover.

4. Remove hardware securing D761-1 support to valve. Do not kink cable.

5. Cut and discard MS3367-4-9 ty-rap secured to D760-1 trigger. Disengage D676-2

cable assembly ball from trigger, but do not kink cable.

6. Remove screws securing D669-3 strap to D669-6 cradle assembly and remove strap.

Carefully remove cylinder.

Depressurization

CAUTION

Use appropriate eye and hearing protection. Do not service

cylinder assembly while cylinder is installed in helicopter.

1. Remove cylinder per Section 32-61 Part A. Verify MT545-1 pin assembly and

MT546-1 diffuser are properly installed.

2. Refer to Figure 32-5. Remove D760-7 cap (etched with “FILL PORT”) from valve

assembly. A loud pop may be heard when cap’s seal is broken.

3. In a well-ventilated area, slowly screw MT546-4 bleed fitting assembly into fill-port

until the noise of escaping gas is heard. Screw fitting in or out to adjust flow rate.

Finish bleeding cylinder with bleed fitting fully in. When noise ceases, verify cylinder

pressure gage indicates zero. Remove bleed fitting.

4. Install cap in valve assembly and special torque cap to 40 in.-lb.

5. Evaluate cylinder life and hydrostatic test status.

Chapter 32 Landing Gear

Page 32.13

32-61 Cylinder Assembly (continued)

C. Filling

CAUTION

Use appropriate eye and hearing protection. Do not service

cylinder assembly while cylinder is installed in helicopter.

WARNING

ONLY cylinders labeled “DOT-E 10915-4945” may be refilled.

Cylinders labeled “DOT-E 10915-4500” must be returned to

RHC for exchange/upgrade.

WARNING

Verify D757-1 (gray) valve assembly is engraved with “D758-4”

or has a data plate indicating B900-8 modification.

Filling equipment (pumps, hoses, fittings, etc.) must be rated for 6000 psi minimum

working pressure and be in good condition.

Cylinder temperature and pressure must be kept within safe limits. Monitor pressure gage

and use thermocouple or other appropriate temperature probe to monitor temperature

on face of thermal relief fitting during fill. Do not allow temperature to exceed 50ºC

(122ºF) or pressure to exceed 5500 psig. If limits are approached, stop fill and allow

cylinder to cool and pressure to drop before continuing. Placing cylinder in a water bath

and using slow to moderate fill rates is recommended. If using water bath, keep water

level below valve assembly to avoid water contamination of valve.

1. Evaluate cylinder life and hydrostatic test status.

2. Refer to Figure 32-5. Install MT545-1 pin assembly in D757-1 valve assembly.

Install MT546-1 diffuser on valve fitting and special torque diffuser to 120 in.-lb.

3. Remove D760-7 cap (etched with “FILL PORT”) from valve assembly. A loud pop

may be heard when cap’s seal is broken.

4. Install MT546-2 adapter assembly into fill port and special torque adapter to 40 in.-

lb. Attach fill hose to adapter.

5. Fill with 99.98% minimum purity (industrial grade) helium per chart below:

Ambient Temperature (ºC)

Pressure (psig)

-20

4268

-10

4437

4606

4776

4945

5114

5283

Page 32.14

Chapter 32 Landing Gear

32-61 Cylinder Assembly (continued)

C. Filling (continued)

6. Allow cylinder and valve to cool to ambient temperature. Top off with helium to

compensate for any pressure loss due to cooling.

7. Remove fill hose and MT546-2 adapter assembly.

8. Remove & discard old o-ring from cap. Lightly coat new MS28778-2 o-ring with

A257-19 lubricant and install o-ring on fill-port cap at base of threads. Install cap in

valve assembly and special torque cap to 40 in.-lb.

D. Installation

WARNING

Verify D757-1 (gray) valve assembly is engraved with “D758-4”

or has a data plate indicating B900-8 modification.

Fill cylinder per Section 32-61 Part C, if not previously accomplished.

Refer to Figure 32-5. Install MT545-1 pin assembly in D757-1 valve assembly.

Hinge right aft seat assembly forward. Verify A701-5 (anti-chafe) tape protects

cylinder where cylinder base contacts cabin structure in three locations. Carefully

position cylinder in D669-6 cradle assembly.

Engage D676-2 cable assembly ball in D760-1 trigger; do not kink cable. Install

MS3367-4-9 ty-rap as shown. Cinch ty-rap until snug without over-tightening, and

trim tip flush with head. Install hardware securing D761-1 support to valve.

Verify cable housing protrudes through clamps on support flush-to-0.200 inch

maximum. Adjust as necessary.

Rotate cylinder as required to minimize cable bending and to ensure clearance with

cabin structure.

Verify D682-6 decal is in specified location. If decal location is incorrect, remove

old decal and install new decal on cylinder. Install screws securing D669-3 strap

to cradle assembly.

Install hardware securing D761-2 cover to valve and D761-1 support.

Remove MT546-1 diffuser, if installed. Connect D674-9 hose assembly to valve

fitting. Orient hose as required to maintain miminum 0.25 inch clearance to cylinder

and adjacent vertical panel. Special torque B-nut per Section 20-33 and torque

stripe per Figure 5-1.

10.

Rig inflation lever and replace shear-rivet per Section 32-62.

Chapter 32 Landing Gear

Page 32.15

32-62 Lever Rigging and Shear-Rivet Replacement

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-9.

WARNING

D679 Cylinder contents are under extreme pressure. Install

MT545-1 pin assembly in D757-1 valve assembly during

maintenance to prevent cylinder discharge.

WARNING

Install MS20470A2-6-5 (or MS20470A2-6.5) annealed rivet in

lever assembly or rivet may be too hard to shear.

Install cylinder per Section 32-61 Part D, if not previously accomplished. Install MT545-1

pin assembly in D757-1 valve assembly.

Refer to Figure 32-6. With no shear-rivet installed, raise collective full up, push in and

rotate D680-1 lever assembly safety to READY position, squeeze lever to remove cable

slack, and verify 1.25 - 1.30 in. between tip of lever and collective stick as shown. As

required, reposition D676-2 cable assembly housing at lever to obtain dimension.

Push in and rotate lever safety to LOCKED position. Simultaneously squeeze lever and

verify no preload in cable thru full collective travel.

Refer to Figure 32-6. Insert MS20470A2-6-5 (or MS20470A2-6.5) rivet in lever as

shown. Using locking pliers or similar, flatten shop-head end of rivet to 0.080-0.100 in.

Verify lever safety is in LOCKED position. Remove MT545-1 pin assembly from D757-1

valve assembly.

Chapter 32 Landing Gear

Page 32.17

32-63 Float Installation

Refer to R66 Illustrated Parts Catalog (IPC) Figure 32-11 and 32-17.

WARNING

D679 Cylinder contents are under extreme pressure. Install

MT545-1 pin assembly in D757-1 valve assembly during

maintenance to prevent cylinder discharge.

A. Removal

NOTE

Floats are subject to damage during removal. Remove floats if

necessary for repairs.

1. Refer to Figure 32-5. Hinge right aft seat assembly forward. Install MT545-1 pin

assembly in D757-1 valve assembly.

2. Disconnect D674-12 hose assembly from T-fitting near float. Cap fittings to prevent

foreign object contamination.

3. Refer to Figure 32-7. Detach float cover hook and loop tape inboard of skid and

loosen lacing.

4. Remove hardware securing float to skid tube, and skid extension.

5. Use care when removing C944 retainer strips from girts, and when separating girts

from skid tube and skid extension. Repeat steps for opposite float.

Installation

1. Refer to Figure 32-7. Verify (outboard) bolt heads securing struts to skids are

covered with B270-1 sealant. Apply additional sealant as required.

2. Position deflated float over skid tube and skid extension. Align holes in C944 retainer

strips, float covers, float girts, and skid and install hardware. Special torque nuts per

Section 20-33.

3. Inflate float with filtered, oil-free, dry air to 3.0 psig at topping valves.

4. Remove caps and connect D674-12 hose assembly to T-fitting near float. Special

torque hose B-nut per Section 20-33, apply B270-22 protectant to exposed aluminum

surfaces on hose B-nut and T-fitting, and torque stripe per Figure 5-1. Repeat steps

for opposite float.

5. Pack floats per Section 32-63 Part C.

Chapter 32 Landing Gear

Page 32.19

Robinson Helicopter Company RTR 660 (Number R00015LA). Maintenance Manual (2012) - page 3