TECHNICAL MANUAL MAINTENANCE MANUAL FOR ARMY CH-47D HELICOPTER (1992)

TM 55-1520-240-10

CONTROLS/

INDICATOR

FUNCTION

CAUTION

RAD ALT dimming

On right side of both in

When operating over dense foliage, the radar

controls

strument panels.

altimeters will indicate the altitude to the tops of

Controls light intensity

the trees. When operating over sparse foliage,

of digital display and HI

the altimeters may indicate the altitude between

and LO caution light.

the ground and about half the average tree

height, depending on ground speed. When

2-200. Normal Operation - Radar Altimeter (AN/APN-

external cargo is carried, the radar altimeter may

209A).

occasionally indicate the distance between the

bottom of the helicopter and the load.

a. Starting.

(1) Set RAD ALT dimming control to desired

(1) Rotate the LO SET knob on the pilot’s

digital display light level.

altimeter until the LO index is at 100 feet. Rotate the HI

set knob until the HI index is at 800 feet. Allow 1 minute

(2) Set HI and LO indexes as desired. If HI or

for warmup.

LO indexes are not desired, set the LO index at 0 feet or the

HI index above 1, 500 feet.

(2) Check for the following indications:

2-200.1. RADAR ALTIMETEIR AN/APN-209( )) Altitude

(a) The pointers indicate between 0 and 2 feet.

Voice Warning System (AVWS). (If Installed by

(b) The digital displays indicate between 0 and 2

MWO 1-1520-240-50-61)

feet.

The RT-I 115F/APN-209 Altitude Voice Warning System

(d) HI caution light is off.

(AVWS) consists of a panel mounted receiver-

(e) OFF flag not in view.

transmitter/height indicator (RT-1115F/APN-209) and two

flush-mounted antennas.

When installed, the height

b. Testing.

indicator is mounted in the pilot instrument panel.

(1) Press and hold the PUSH-TO-TEST knob.

Check for the following indications:

The face of the altitude voice warning radar altimeter (RT-11

15F/APN-209) is exactly the same as that of the visual only

(a) OFF flags not in view.

AN/APN-209A radar altimeter, with the operation being the

(b) Pointers indicate between 900 feet and

same as outlined in section 2-198. The difference is only

1,100 feet.

internal. A transmitter added internally sends out an aural

warning to the pilot, copilot, and flight engineer interphone

and 1,100 feet.

station ICS panels when the helicopter descends below the

(d) LO caution light is off.

low index setting or rises above the high index setting (in

(e) HI caution light is on.

addition to the LO or HI caution lights).

(2) Release the PUSH-TO-TEST knob. Check

NOTE

that all indications return to those specified in step a.(2).

The voice portion of the system works off a 10

second clock. If a transition is made thru either

NOTE

Preset, back to the original warning condition within

The LO caution light may appear to go out.

this time frame, the voice warning will stay at its

However, the light will be visible with night vision

original volume level.

goggles. In bright daylight, it may be necessary

to shade the indicator to verify operation of the

The volume of the aural warning message can be adjusted

dimming control.

by the flight crew. On initial transition the volume is always

set to Full. By momentarily pressing the PUSH-TO-TEST

(3) Rotate the RAD ALT dimming control from

(PTT) knob once, the message is decreased to 1/2 the

BRT to DIM. Check that the digital display dims and

volume. Momentarily pressing the PTT knob a second time

goes out. Check that the LO caution light dims but does

disables the aural warning message. Regardless of the

not go out completely.

volume level, when the aircraft transitions back through

either Preset (HI or LO) (from caution light Off to On), the

(4) Repeat on copilot’s instrument.

volume level of the aural warning message will return to Full.

c. Inflight operation.

Change 6 2-75

TM 55-1520-240-10

2-200.2. Controls and Function, Radar Altimeter

(1) Rotate the LO SET knob on the pilot’s altimeter

(AN/APN-209()) (AVWS).

until the LO index is at 100 feet. Rotate the HI set knob

until the HI index is at 800 feet. Allow 1 minute for

CONTROLS/

warmup.

INDICATOR

FUNCTION

(2) Check for the following indications:

LO SET knob

The LO SET knob applies

(a) The pointers indicate between 0 and 2 feet.

power to altimeter system. LO

(b) The digital displays indicate between 0 and 2

set index on both pilot’s

feet.

altimeters

can

set

independently. Both LO set

(d) Low altitude warning (“ALTITUDE LOW, TOO

indexes must be masked to

LOW") is heard in the headset.

turn the set off.

(e) HI caution light is off.

(f) OFF flag not in view.

HI SET knob

Sets position of HI set index

b. Testing.

when turned.

Adjusts the

NOTE

warning message volume level

Connect monitor headset to the aircraft ICS.

and tests altimeter system

when pressed.

(1) On the AN/APN-209( ) indicator, rotate the

and tests altimeter system whenLOSET knob to a point

LO set index

Indicates altitude trip point for

just above the OFF detent. Adjust HI SET knob to

LO caution light.

position the HI index to 100 feet. Allow 1 minute for

warmup. Verify the following:

HI set index

Indicates altitude trip point for

HI caution light

(a) The indicator pointer reads 0 to 2 feet.

(b) The digital display reads 0 to 2 feet.

Indicator pointer

Indicates absolute altitude from

0 to 1, 500 feet.

(2) Verify low altitude warning ("ALTITUDE LOW,

TOO LOW”) is NOT heard in the headset.

Digital indicator

Provides direct reading four

(3)

Adjust LO index to approximately 10 feet

digit indication of absolute

position on indicator. Verify the following:

altitude from 0 to 1,500 feet.

(a) The LO warning lamp is illuminated.

(b) The low altitude warning, “ALTITUDE

LO caution light

Comes on when helicopter

LOW, TOO LOW" is heard, clear and distinctly, in

descends below altitude on LO

headset and at FULL volume. Audio warning repeat

set index.

interval is 10 (+1) seconds. Momentarily press the

PUSH- TO-TEST knob once and verify the message is

HI caution light

Light

comes

when

at ½ volume. Momentarily press the PUSH-TO-TEST a

helicopter rises above altitude

second time and verify the warning message is OFF.

on HI set index.

the OFF detent. Check that system is still functional and

OFF flag

Flag is displayed when power

LO warning lamp is extinguished. Wait 11 seconds

is removed from set, when

before proceeding to the next step.

indications are unreliable,

(4) Readjust the LO index to approximately 10 feet

when

altitude

exceeds

position on indicator.

The LO warning lamp is

approximately 1,500 feet.

illuminated and the low altitude warning, “ALTITUDE

LOW, TOO LOW”, is audible at FULL volume.

RAD ALT dimming

On right side of both controls

(5) Press and hold the PUSH-TO-TEST knob to

instrument panels. Controls

actuate the PUSH-TO-TEST condition. Verify the

light intensity of digital display

following:

and HI and LO caution light.

(a) OFF flags not in view.

(b) Pointers indicate between 900 feet and

2-200.3 Normal Operation - Radar Altimeter

1,100 feet.

(AN/APN-209()) (AVWS).

a. Starting.

1,100 feet.

NOTE

(d) LO caution light is off.

Connect monitor headset to the aircraft ICS.

2-76 Change 6

TM 55-1520-240-10

(e) HI caution light is o2-201. VERTICAL SPEED Indicator.

(f) The high altitude warTwo VERTICAL SPEED indicators are

HIGH, CHECK ALTITUDE’, is audiblpanel (fig. 2-They

dindicate the ra

10 second intervals throughout tbased on

the rate of changeThe atm

indicator is a direct-reading pres

(6) Release the PUSH-TO-TEST knob. Check that

no electrical power for operation

all indications return to those specified in step b.(4).

2-202. Attitude Indicator.

NOTE

Two attitude indicators are on the

The LO caution light may app8 and 2-10). The attitude indicato

However, the light will be vtailored for the flight characteri

vision goggles. In bright dainclusion of an electrical trim ca

necessary to shade the indicaaddition to the stNormal flight at

tion of the dimming control.

of helicopters, defined by fixed a

pitch, are easily trimmed unto thi

(7) Rotate the RAD ALT dimming control from

operation of the helicopter in an

BRT to DIM. Check that the digital display dims and

facilitated. Degrees of pitch and

goes out. Check that the LO caution light dims but does

movement of a universally mounted

not go out completely.

black and light gray to symbolize

ng the two

(8) Set gain controls on thhorizon line separati

elation to

flight engineer interphone statiminiature aircraft in r

ose upoand

the minimum (counter-clockwise)The pitch adjustmento n

(3) thru

Verify that the voice nose down. To compensate attitude

discernable in the headset at auppereknThe r

minimum in either direction.

c. Inflight operation.

NOTE

CAUTION

Rapid rotation of the pitch and

When operating over dense foliage, the radar

the attitude indicator may caus

altimeters will indicate the altitude to the tops

roll attitude changes with AFCS

of the trees. When operating over sparse

The indicator incorporates integra

foliage, the altimeters may indicate the altitude

copilot attitude indicators shoul

between the ground and about half the average

seconds after electrical

ower to

tree height, depending on ground sped.

operate the attitude indicator gym

When extend cargo is carried, the radar

1 and No. 2 AC bus through the N

altimeter may occasionally indicate the dis-

NAV COPLT VGI circuit breakers on

tance between the bottom of the helicopter and

2 PDP.

the load

ndicator (VGI)

(1) Set RAD ALT dimming co2-203. Pilot and Copilot Attitude I

digital display light level.

switch.

the instrumen

(2) Set HI and LO indexes A VGI switch is on

2-8 and

helicopter exceeds one of theseattitude indicator (fig.

en the s

message will be heard at full labeled NORM and EMER. Wh

volume level can be decreased by one-half

(1/2) by

pressing the PUSH-TO-TEST once or inhibited by press-

ing PUSH-TO-TEST a

If HI or LO indexes

are not desired. set the LO index at O feet or the HI index

above 1,500 feet.

Change

2-76.1

TM 55-1520-240-10

NORM, each attitude indicator opa. SELECT Button. I

t allows the select

rate gyro. If either the pilot three modes on the four-di

git display:

signaled by the OFF flag on thtime), or ET (elapse

d time). The six-di

switching to the remaining gyroGMT only.mplished by

placing the respective VGI switch to EMER. The

n. It is used to set

switching of the gyros from NORMb. CONTROL Burto

is accomplished by a gyro transfselected.onatheefour-digit display. Wh

gyro will also result in failureTROLtandaSELECT buttons are pressed

Power is supplied by the No.

2neously,ttheufour-digit display is cha

NAV CONT VGI circuit breaker onnormal.

to2 PDP.time set mode, and the

button is functional.

2-204. Turn and Slip Indicator (4-Minute Type).

C. DIM Control Switch. It is used to

Each turn and slip indicator (intensity of

the display. At low light

controlled by an electrically acdisplay is NVG compatible.

ment has a pointer (turn indicator) and a ball (slip

Integral alkaline batteries maintain

indicator). Power to operate the gyros is supplied by the

when no aircraft power is applied, but

DC essential bus through the NAV TURN & SLIP

and SELECT buttons arc disabled. Power

circuit breakers on the No.

1 and No.

2 PDP.

the chronometers is supplied by the DC

through the CPLT CLOCK and PLT CLOCK o

2-205. Magnetic Compass.

No. 1 PDP and No. 2 PDP.

The magnetic compass is mounted on top of the center

instrument panel glareshield (fi2-208.

No2-Operation - CHRONOMETER.

reading instrument requiring no electrical power. It

2-209. Setting GMT.

the SELECT button un

consists of a compass card mounted on a maPressc

GMT is selected. Simultaneously press

element in a liquid-filled bowl.

LECT and CONTROL buttons to enter the

2-206. Free Air Temperature Gauge.

The tens of hours digit will start fl

CONTROL button has full control of the

The free air temperature gauge is on the exterior of the

Each time the CONTROL button is pressed

pilot’s eyebrow window (fig.

2-4). The unit is calibrated

ing digit will increment. Once the tent

in degreesofto

o+50

pressing the SELECT button will select t

be set. After the last digit has been s

2-207. CHRONOMETER.

the CONTROL button, press the SELECT

Two digital clocks labeled CHROexit the set mode. The annunciator wi

cated on the copilot and pilotnormalmflashinglcondition to indicate

2-50). Each clock has a six-digiclock is running.mean

time) display and a four-digit selectable display. A test

mode is provided to check system2-210.ASettingaLT.hingPressunthe

SELECT button un

ator identifies which clock modLT is selected. Simultaneously press bo

There are three controls on eaand CONTROL buttons

to enter the set mo

button, a CONTROL button, and aof hours digit will start flashing and

button has full control of the flashin

same sequence as for setting GMT with

that the minutes are already synchron

GMT clock and can not be set when in L

2-211. Setting ET.

The elapsed time allows for

up or count down modes.

a. Count Up. Press the SELECT button

selected. Press the CONTROL button to s

sequence. The clock will count up to

seconds and then changes to hours and

count up to

99 hours and

59 minutes.

CONTROL button again resets the ET to

b. Count

Press the SELECT button unti

is selected. Simultaneously press both

CONTROL buttons to enter the set mode

down from any time, not to exceed

59 m

seconds, can be set using the same se

setting GMT. Once the last digit is s

SELECT button exits the set mode and

Figure

2-50. Chronometer

ready to start count down. Pressing t

2-76.2 Change

TM 55-1520-240-10

button will start count down sequence. When the clock

2-5 1.1). Each capsule is labeled with word segments which

reaches zero, an alarm becomes active by flashing the

are related to the fault or condition. When a caution capsule

numbers and the ET counter will begin to count up. To reset

illuminates, the word segments lettered into the panel are of

the alarm press either the SELECT or CONTROL button.

an amber color. When they extinguish, the lettering is not

readable. Tables 2-2 and 2-2.1 contain lists of the word

2-212. Test Mode.

To activate the test mode, press and

segments displayed on the capsules and their actual mean-

hold the SELECT button for three seconds and all numerical

ing and cause.

displays will show an 8 and all annunciators will be active.

An NVG filter is provided for use during NVG operations.

2-213. Master Caution System.

The filter fits over the master caution panel and is secured

in place by hook and pile tape at its base. When the filter is

The master caution system provides the pilots with a visual

in this position, any light coming from the caution lights

indication of helicopter conditions or faults (fig. 2-51 and

will be NVG compatible. For normal operations, the filter is

2-51.1). The components of the systems are the master

rotated from its base to a horizontal position, and stowed in

caution panel with NVG filter, two MASTER CAUTION

a compartment above the master caution panel.

lights with NVG filters, and a CAUTION LT panel with a

TEST and a BRT-DIM switch. Power to operate and control

2-215. MASTER CAUTION Lights. T

MASTER

the master caution system is supplied by the DC essential

CAUTION lights on the instrument panels indicate that one

bus through the LIGHTING CAUTION PNL circuit breaker

or more of the caution capsules have illuminated. On the

on the No. 1 PDP.

pilot instrument panel, the caution light is above the

airspeed indicator. On the copilot instrument panel, it is

2-214. Master Caution Panel.

The master caution

above the altimeter.

panel is on the center instrument panel (fig. 2-51 and

A66987

Figure 2-51.

Master Caution System

712

Change 13

2-76.3/(2-76.4 blank)

TM 55-1520-240-10

Table 2-2.

Master Caution Panel Capsules

712

WORD SEGMENT

EXPLANATION

XMSN OIL HOT

Transmission oil temperature is more than 140°C.

XMSN OIL PRESS

Transmission main oil pressure is less than 20 psi, or less than 10 psi in the aft rotor shaft.

XMSN AUX OIL PRESS

Less than 20 psi auxiliary oil pressure in the forward, or aft transmission or less than 10 psi in the combining transmis-

sion.

NO. 1 ENG OIL LOW

Approximately 2 qt of usable oil is remaining in No. 1 engine oil tank.

NO. 2 ENG OIL LOW

Approximately 2 qt of usable oil is remaining in No. 2 engine oil tank.

L FUEL PRESS

Left fuel pressure is below 10 psi.

R FUEL PRESS

Right fuel pressure is below 10 psi.

PWR STEER

Steering control has been disabled due to system malfunction or steering limits have been exceeded.

NO. 1 HYD FLT CONTR

No. 1 flight control hydraulic system pressure is below 1,800 psi.

NO. 2 HYD FLT CONTR

No. 2 flight control hydraulic system pressure is below 1,800 psi.

UTIL HYD SYS

Utility hydraulic system pressure is below 1,800 psi.

PARK BRAKE ON

Parking brake is on.

NO. 1 RECT OFF

Transformer-rectifier has failed or the generator output is interrupted.

NO. 2 RECT OFF

Transformer-rectifier has failed or the generator output is interrupted.

NO. 1 GEN OFF

No. 1 generator is inoperative or the generator switch is at OFF.

NO. 2 GEN OFF

No. 2 generator is inoperative or the generator switch is at OFF.

BATT SYS MAL

Battery or battery charging system has failed or the battery has exceeded the safe operating temperature.

EXT PWR

This light comes on whenever external power is connected to the bus.

L FUEL LOW

Left main fuel tank has approximately 20 percent of fuel remaining.

R FUEL LOW

Right main fuel tank has approximately 20 percent of fuel remaining.

HEATER HOT

Temperature within heater is greater than 177°C.

MID HOOK OPEN

The midcargo hook has been opened, either hydraulically, pneumatically, or manually.

APU ON

The APU is up to speed and can be used.

DUAL HOOK FAULT

The forward and/or aft hook circuit has an electrical fault and the hook(s) shall not be released electrically.

FWD HOOK OPEN

The forward cargo hook has been opened either electrically or manually.

AFT HOOK OPEN

The aft cargo hook has been opened either electrically or manually.

NO. 1 AFCS OFF

The No. 1 AFCS is off, failed, or DASH is reprogramming.

NO. 2 AFCS OFF

The No. 2 AFCS is off, failed, or DASH is reprogramming.

NO. 1 ENG CHIP DET

Metal chips in No. 1 engine or engine transmission oil.

NO. 2 ENG CHIP DET

Metal chips in No. 2 engine or engine transmission oil.

XMSN CHIP DET

Metal chips in the oil of the forward, combining, or aft transmissions or the aft thrust bearing.

NO. 1 ENG N1 CONT

No. 1 engine N1 component has failed or the engine condition lever or N1 actuator is not in the STOP, GND, or FLT

position.

NO. 2 ENG N1 CONT

No. 2 engine N1 component has failed or engine condition lever or N1 actuator is not in the STOP, GND, or FLT posi-

tion.

NO. 1 ENG XMSN HOT

No. 1 engine transmission oil temperature is above about 190°C.

NO. 2 ENG XMSN HOT

No. 2 engine transmission oil temperature is above about 190°C.

CM INOP

Countermeasures set has failed.

CM JAM

Countermeasures set has detected interference from other countermeasures sets or system is being jammed.

Movable NVG filters are attached to the instrument panels

Once the malfunction is corrected, the affected caution

to the left of each light. For NVG operations, the filters can

capsule will extinguish. The HEATER HOT capsule is an

be rotated over the two MASTER CAUTION lights making

exception (Refer to Section X). If either generator is cycled

the lights NVG compatible. After the MASTER CAUTION

OFF then ON while another caution capsule is lit, the

light has illuminated and the condition noted, the pilots

MASTER CAUTION light may remain illuminated after

should extinguish the MASTER CAUTION light by press-

the generator comes back on and the associated GEN OFF

ing (PUSH TO RESET) the face of the light. The MASTER

capsule extinguishes. If this occurs, press to extinguish the

CAUTION light is then ready to indicate a subsequent

MASTER CAUTION light.

malfunction of a different system.

Change 13

2-77

TM 55-1520-240-10

A73387

Figure 2-51.1.

Master Caution/Advisory Panel

2-216. CAUTION LT Panel.

The CAUTION LT (cau-

b. TEST Switch.

When the switch is placed to TEST, all

tion light) panel is located on the center instrument panel

the caution capsules on the master caution panel and the two

(fig. 2-51). It comprises of a. BRT-DIM switch and a TEST

MASTER CAUTION lights illuminate to facilitate check-

switch.

ing the individual capsule lamps. When released to OFF, the

lamps in the MASTER CAUTION lights and all the caution

a. BRT-DIM Switch.

When the switch is placed to BRT,

the caution capsule will light to full intensity. When moved

capsules extinguish. When the PLT INST and CPLT INST

to DIM, the caution capsules will not be as bright. When the

lights rotary control switches are active, and the VHF NAV

cockpit dome lights are on white, it is not possible to dim

and marker beacon VOL switches are on, the test feature

the master caution panel. If the white dome light is selected

will also light all the select legends on the MODE SELECT

while the caution lights are operating on DIM, the caution

panel and the MKR BCN indicator lights.

lights will automatically switch to BRT mode of operation.

2-78

Change 13

TM 55-1520-240-10

Table 2-2.1.

Master Caution/Advisory Panel Capsules

WORD SEGMENT

EXPLANATION

ENG 1 FAIL

Power turbine shaft failure, Nl underspeed, or flameout. During engine start this caution is illuminated if the engine

fails to start.

ENG 2 FAIL

Power turbine shaft failure, N1 underspeed, or flameout. During engine start this caution is illuminated if the engine

fails to start.

FADEC 1

No. 1 PRI system hard fails.

ENG CONT PWR

PTIT is within contingency power range.

FADEC

No. 2 PRI system hard fails.

REV 1

No. 1 REV system hard fails.

REV 2

No. 2 REV system hard fails.

ENG 1 OIL LVL

Approximately 2 qt of usable oil is remaining in No. 1 engine oil tank.

EAPS 1 FAIL

Pressure switch within No.1 EAPS has sensed a pressure differential of 10 psi, indicating a partial blockage of inlet air.

EAPS 2 FAIL

Pressure switch within No.2 EAPS has sensed a pressure differential of 10 psi, indicating a partial blockage of inlet air.

ENG 2 OIL LVL

Approximately 2 qt of usable oil is remaining in No. 2 engine oil tank.

ENG 1 CHIP DETR

Metal chips in No. 1 engine or engine transmission oil.

XMSN OIL HOT

Transmission oil temperature is more than 140°C.

XMSN CHIP DETR

Metal chips in the oil of the forward, combining, or aft transmissions or the aft thrust bearing.

ENG 2 CHIP DETR

Metal chips in No. 2 engine or engine transmission oil.

ENG 1 XMSN HOT

No. 1 engine transmission oil temperature is above about 190°C.

XMSN OIL PRESS

Transmission main oil pressure is less than 20 psi, or less than 10 psi in the aft rotor shaft.

ENG 2 XMSN HOT

No. 2 engine transmission oil temperature is above about 190°C.

L FUEL LVL

Left main fuel tank has approximately 20 percent of fuel remaining.

XMSN AUX OIL PRESS

Less than 20 psi auxiliary oil pressure in the forward, or aft transmission or less than 10 psi in the combining transmis-

sion.

R FUEL LVL

Right main fuel tank has approximately 20 percent of fuel remaining.

L FUEL PRESS

Left fuel pressure is below 10 psi.

HTR HOT

Temperature within heater is greater than 177°C.

R FUEL PRESS

Right fuel pressure is below 10 psi.

RECT 1

Transformer-rectifier has failed or the generator output is interrupted.

BATT SYS MALF

Battery or battery charging system has failed or the battery has exceeded the safe operating temperature.

PWR STEER

Steering control has been disabled due to system malfunction or steering limits have been exceeded.

RECT

Transformer-rectifier has failed or the generator output is interrupted.

GEN 1

No. 1 generator is inoperative or the generator switch is at OFF.

GEN 2

No. 2 generator is inoperative or the generator switch is at OFF.

HYD 1

No. 1 flight control hydraulic system pressure is below 1,800 psi.

CM JAM

Counter measures jammer failed.

UTIL HYD SYS

Utility hydraulic system pressure is below 1,800 psi.

HYD 2

No. 2 flight control hydraulic system pressure is below 1,800 psi.

AFCS 1

The No. 1 AFCS is off, failed, or DASH is reprogramming.

CM INOP

Counter measures inoperative.

DUAL HOOK FAULT

The forward and/or aft hook circuit has an electrical fault and the hook(s) shall not be released electrically.

AFCS

The No. 2 AFCS is off, failed, or DASH is reprogramming.

APU ON

The APU is up to speed and can be used.

EXT PWR

This light comes on whenever external power is connected to the bus.

FWD HOOK OPEN

The forward cargo hook has been opened either electrically or manually.

PARK BRK ON

Parking brake is on.

MID HOOK OPEN

The midcargo hook has been opened, either hydraulically, pneumatically, or manually.

AFT HOOK OPEN

The aft cargo hook has been opened either electrically or manually.

Change

2-79

55-1520-240-10

SECTION XV

SERVICING, PARKING, AND MOORING

2-217. General.

not available. This usually occurs duri

flights where aircraft using NATO F-44 (J

This section contains instructions on servicing, parking, and

with NATO F-40 (JP-4) or Commercial ASTM T

mooring the helicopter. These instructions include only those

When this occurs. engine operating char

tasks which a flight crew may be expected to perform when

change in that lower operating temperatur

away from a military maintenance support activity. Diagrams

tion. lower engine speed, easier starting

and tables are provided depicting servicing points, materials,

may be experienced. The reverse is true w

and walkways.

F-40 (JP-4) fuel to F-44 (JP-5) or Commer

2-218. Servicing.

A-l fuels.

Safe walkway areas, no step areas, and no hand holds are

depicted in Figure 2-52. Servicing points areWARNING

ure 2-53. Table 2-3 lists the approved materials, specifica-

tions and capacities. Table 2-4 listTo prevent fuel from spilling from the tanks,ents

for oils.

caution should be used when opening fuel caps

after pressure refueling or when the aircraft

2-219. Fuel Types.

has been sitting in the sun.

The following describe the various types of fuels:

2-221. Fuel Tanks Servicing.

a. Army StandaJP

4 is the Army-designated

The CH-47D helicopter has six fuel tanks,

primary fuels adopted for worldwide use.

side. The tanks can be serviced through

b. AlternatT

ese are JP-5, JP-8, and equiva-

pressure refueling system or through fille

lent commercial fuels which can beThe single-

point method of servicing is p

out power reduction when Army standard fuel is not avail-

method, all tanks can be filled, partiall

able. Power setting adjustments afilled in less than 4 m

inutes. Refer to t

may be required when an alternate fuel is used.

tank capacities.

c. Emergency100LLs(Low Lead) AVGA222. Single--

Point Pressure Refueling.

ation gasoline) is authorized for use as an emergency fuel with

The pressure refueling control panel and

operation not to exceed 6 hours cumulative time.

are on the right side of the helicopter a

2-220. Use of Fuels.

ing gear (fig. 2-25). Thelanding gear ac

opened to expose the panel and receptacle

Consult TB 55-9150-200-24 for use of fuel and substitute data

ing adapter is located on the structure a

as applicable for turbine engine aircraft. (Refer to tables 2-3,

tacle.

2-5, and 2-6).

Be sure the heli

50 feet from any han-

a.There is no special limitation on the use of Army stan-

gar or structure.

dard or alternate fuel. Certain limitations are imposed when

emergency fuels are used. For recordb. Be sure the refue10ifeet from the le

shall be identified as to the majohelicopter. of the mixture.

c. Electrically ground the helicopter

b.The use of kerosene fuels (JP-5 or JP-8 type) in turbine

engines dictates a need for speciaas follows:ns. Ground starts

and air restarts at low temperature m(1)Connect one end of ground cable to t

to low vapor pressure.

gear eyebolt or to the jack on the right

other end to a grou

c. When changing from one type sta 115. Connect theo

ble has no br

another - for example, JP-4 to JP-ground point. Be sure the ca

clips are securely attached to the cable

sary to drain the aircraft fuel system before adding the new

fuel.

(2)Be sure the fueling unit is grounde

ground point as the helicopter.

d. Fuels having the same NATO code number are inter-

changeable. Jet fuels conforming tod. At the cockpit overhead FUEL CONTR

tion may be used when MIL-T-5624 orREFUEL STA switch to

ON.

2-80

Change

TM 55-1520-240-10

Table 2-3. Servicing

CAPACITY

SERVICEABLE ITEM

MATERIAL

SPECIFICATION

(See note A)

L Main Tank

JP-4, JP-5

MIL-T-5624

278 Gallons

R Main Tank

or JP-8

MIL-T-83133

274 Gallons

L Fwd Aux Tank

JP-4, JP-5

MIL-T-5624

122 Gallons

R Fwd Aux Tank

or JP-8

MIL-T-83133

119 Gallons

L Aft Aux Tank

JP-4, JP-5

MIL-T-5624

118 Gallons

R Aft Aux Tank

or JP-8

MIL-T-83133

117 Gallons

ERFS II Tank 1,

JP-4, JP-5

MIL-T-5624

825.5 Gallons

2, or 3

or JP-8

MIL-T-83133

825.5 Gallons

Each Engine Oil Tank

Lubrication Oil

MIL-L-23699 or MIL-L-7808

12 Quarts

(See note C)

APU Engine Oil

Lubrication Oil

MIL-L-7808 or MIL-L-23699

3 Quarts

(See note C)

Forward Transmission

Lubrication Oil

DOD-L-85734 or MIL-L-23699

26 Quarts

(See note C)

Aft Transmission

Lubrication Oil

DOD-L-85734 or MIL-L-23699

41 Quarts

(See note C)

Combining Transmission

Lubrication Oil

DOD-L-85734 or MIL-L-23699

20 Quarts

(See note C)

Engine Transmission (each)

Lubrication Oil

DOD-L-85734 or MIL-L-23699

10 Quarts

(See note C)

Each Flight Control System Reservoir

Hydraulic Fluid

MIL-H-83282 (See note B)

2 Quarts

Utility Hydraulic System Reservoir

Hydraulic Fluid

MIL-H-83282 (See note B)

6 Quarts

Rotor Head Oil Tanks

Lubrication Oil

MIL-L-7808

As Required

Shock Absorbers and Landing Gear Shock Struts

Hydraulic Fluid

MIL-H-5606

As Required

Swashplates

Grease

MIL-G-81322

As Required

Tires-8.50 x 10 Type III, Forward and Aft

Air/Nitrogen

88 PSI

Accumulators

Air/Nitrogen

BB-N-411

Apu Start

Brakes

Power Steering/Swivel Lock

Signal Accumulator

Utility Reservoir

No. 1 and No. 2 Flight Control

WARNING

Synthetic oils, such as MIL-L-23699, DOD-L-85734 and MIL-L-7808, may soften paint or stain

clothing upon contact. If synthetic oil is spilled on painted surfaces, those surfaces should be

cleaned immediately. Skin should be thoroughly washed after contact and saturated clothing should

be removed immediately. Prolonged skin contact with synthetic oils may cause a skin rash. Areas

where synthetic oils are used should have adequate ventilation to keep mist and fumes to a mini-

mum.

NOTES:

These are maximum capacities which include residual and trapped oil. Servicing capaci-

ties will be less.

Hydraulic fluid MIL-H-5606 may be used when MIL-H-83282 is not available.

When FAT is below -32_C, use MIL-L-7808.

2-86

Change 14

TM 55-1520-240-10

Table 2-4. Equivalent Oils and Hydraulic Fluids

APPROVED DOMESTIC COMMERCIAL OILS FOR MIL-L-23699

Manufacturer’s Designation:

PQ Turbine Lubricant 6423/6700/3889/C3788/9598

Brayco

8991899-G

Castrol 5000

EMGARD Synthesized Turbine Lubricant

2592/2949

EXXON 2380

ESSO Turbo Oil 2830

HATCOL 3211/3611/1639/1680

Mobil RM-139A/147A/247A/246A/249A/250A/270A

Royco

899/899B/899C/899HC/899E-11899E-2

Aeroshell Turbine Oil

500

Stauffer Jet II E-7603

APPROVED DOMESTIC COMMERCIAL FLUIDS FOR MIL-H-5606

Manufacturer’s Designation:

PQ 2890/2863/2903/2905/2950/4140/3808/4328

Mobil Aero HFD

Stauffer Aero Hydroil 500

Brayco

757B/756F/756ES/756E

Brayco Micronic 756ES

TEXACO Aircraft Hydraulic Oil 15/TL-1071 1

Chevron Aviation Hydraulic Fluid D PED 5225

Penreco Petrofluid

4606/4146/4607

Royco

756C/756D/756E

Castrol Hyspin A

Aeroshell Fluid 41

APPROVED DOMESTIC COMMERCIAL FLUIDS FOR MIL-H-63282

Manufacturer’s Designation:

Royco

782 E-1/782 E-2

Gulf TS-741

Brayco Micronic 882/882A

Royco

782/782-1/782-2

Aeroshell Fluid 31

American Oil PQ3883/4219/4401B/4627/4268/4362C/4401/4401A/4923/4908

Emery

2946A/2942/2857/2858

HATCOL

4283/4284/4285

Penreco Petrofluid

822

APPROVED DOMESTIC COMMERCIAL FLUIDS FOR MIL-L-7808

Manufacturer’s Designation:

Aeroshell Turbine Oil 308

American Oil PQ Turbine Oil

8365/9900/4236

Castrol

399

Brayco

880

EXXON Turbo Oil 2389/2391

HATCO 1278/1280

Mobil RM-272A/248A

Royco

808H/808HC

Technolube SYN TURBO No. 3

2-87

TM 55-1520-240-10

Table 2-5. JP-4 Equivalent Fuel

JP-4 EQUIVALENT FUELS

MILITARY FUEL

U.S.

JP-4 (MIL-T-5624)

NATO

F-40 (Wide cut type)

COMMERCIAL FUEL (ASTM-D-1655) JET B*

American Oil Co.

American JP-4

Atlantic Richfield, Richfield Div.

Arcojet B

B.P. Trading

B.P.A.T.G.

Caltex Petroleum Corp.

Caltex Jet B

Chevron

Chevron B

Continental Oil Co.

Conoco JP-4

EXXON Co., USA

EXXON Turbo Fuel B

Gulf Oil

Gulf Jet B

Mobil Oil

Mobil Jet B

Phillips Petroleum

Philjet JP-4

Shell Oil

Aeroshell JP-4

Texaco

Texaco Avjet B

Union Oil

Union JP-4

FOREIGN FUEL (F-40)

Belgium

BA-PF-2B

Canada

3GP-22F

Denmark

JP-4 MIL-T-5624

France

Air 3407 A

Germany (West)

VTL-9130-006

Greece

JP-4 MIL-T-5624

Italy

AA-M-C-1421

Netherlands

JP-4 MIL-T-5624

Norway

JP-4 MIL-T-5624

Portugal

JP-4 MIL-T-5624

Turkey

JP-4 MIL-T-5624

United Kingdom (Britain)

D. Eng RD 2454

* Commercial fuel such as ASTM-D-1655 not containing a icing inhibitor per MIL-I-27686 (commercial name is “PRIST”). Use PRIST in ac-

cordance with instructions on the can. Anti-icing and Biocidal Additive for Commercial Turbine Engine Fuel - The fuel system icing inhibitor

shall conform to MIL-L-27686. The additive provides anti-icing protection and also functions as a biocide to kill microbial growths in helicop-

ter fuel systems. Icing inhibitor conforming to MIL-I-27686 shall be added to commercial fuel not containing an icing inhibitor during refuel-

ing operations, regardless of ambient temperatures. Refueling operations shall be accomplished in accordance with accepted commercial pro-

cedures. Commercial product PRIST conforms to MIL-I-27686.

2-88

TM 55-1520-240-10

Table 2-6. JP-5 and JP-8 Equivalent Fuel

JP-5 AND JP-8 Equivalent FUELS

MILITARY FUEL

U.S.

JP-5 (MIL-T-5624)

JP-8 (MIL-T-83133)

NATO

F-44

F-34

COMMERCIAL FUELS (ASTM-D-1655) JET A/JET A-1*

American type A

American Oil Co.

Atlantic Richfield

ArcoJet A

Arcojet A-1

Richfield Div.

Richfield A

Richfield A-1

B.P. Trading

B.P.A.T.K.

Caltex Petroleum Corp.

Caltex Jet A-1

Chevron

Chevron A-50

Chevron A-1

Cities Service Co.

CITGO A

Continental Oil Co.

Conoco Jet-50

Conoco Jet-60

EXXON Co., USA

EXXON A

EXXON A-1

Gulf Oil

Gulf Jet A

Gulf Jet A-1

Mobil Oil

Mobil Jet A

Mobil Jet A-1

Phillips Petroleum

Phillijet A-SO

Shell Oil

Aeroshell 640

Aeroshell 650

Sinclair

Superjet A

Superjet A-1

Standard Oil Co.

Jet A Kerosene

Jet A-1 Kerosene

Texaco

Avjet A

Avjet A-1

Union Oil

76 Turbine Fuel

FOREIGN FUELS (NATO F-44)

Canada

3-GP-24e

West Germany

UTL-9130-007/UTL-9130-0l0

Italy

AMC-143

Netherlands

D. Eng RD 2493

United Kingdom (Britain)

D. Eng RD 2498

* Commercial fuel such as ASTM-D-1655 not containing a icing inhibitor per MIL-I-27686 (commercial name is “PRIST’). Use PRIST in ac-

cordance with instructions on the can. Anti-icing and Biocidal Additive for Commercial Turbine Engine Fuel - The fuel system icing inhibitor

shall conform to MIL-L-27686. The additive provides anti-icing protection and also functions as a biocide to kill microbial growths in helicop-

ter fuel systems. Icing inhibitor conforming to MIL-I-27686 shall be added to commercial fuel not containing an icing inhibitor during refuel-

ing operations, regardless of ambient temperatures. Refueling operations shall be accomplished in accordance with accepted commercial pro-

cedures. Commercial product PRIST conforms to MIL-I-27686.

2-89

TM 55-1520-240-10

CAUTION

(2) Set the ALL TEST switch to FLOW.

(3) Rotate the FUEL QUANTITY selector

Be sure the fueling station fuel quantity

switch to the tank to be filled. The indicator pointer will

indicator is operating before pressure fuel-

indicate tank fuel quantity.

ing. If the indicator is not operating, the fuel

shutoff valves cannot be checked properly

(4) Set the FUEL CELL SHUTOFF VALVE

and fuel cell overpressurization may result.

TEST switch of the tank to be filled to FLOW.

(5) Open the flow control valve.

e. Open the right forward landing gear access panel

(6) When the desired fuel level is reached, set

and perform the following check:

the FUEL CELL SHUTOFF VALVE TEST switch to

(1) Set the PWR switch to ON. Check that both

PRI OFF.

REFUEL VALVE POSN lights momentarily illumi-

(7) Repeat steps

(3),

(4), and (6) on each tank

nate, then extinguish. If either light illuminates and

until the desired amount of fuel is in each tank.

does not extinguish, the associated refueling valve has

failed and fuel will not flow into that aft auxiliary tank.

(8) Close the flow control valve and disconnect

If the fuel in this tank is required to complete the

the nozzle and ground cable.

mission, notify maintenance.

i. Set the PWR switch to OFF. Check that the

(2) If required, set the LIGHT switch to ON.

REFUEL VALVE POSN lights momentarily illumi-

(3) Set the FUEL QUANTITY selector switch to

nate, then extinguish. If either light does not illuminate

TOTAL.

on, then extinguish, the fuel in that aft auxiliary tank is

unusable. Notify maintenance.

(4) Set the ALL TEST switch to PRI OFF.

j. Close the landing gear access door.

(5) Connect the grounding wire to the grounding

receptacle and connect the fueling nozzle to the adapter.

k. Remove ground cables from the helicopter.

CAUTION

l. Set the REFUEL STA switch on the FUEL

CONTR overhead panel to OFF.

If either the primary or secondary float

switch for any tank is inoperative, do not

CAUTION

pressure refuel that tank unless the fuel cap

is removed to prevent possible fuel cell over-

Perform steps m., n., and o. if helicopter will

pressurization. If both switches are inopera-

not be operated immediately. Failure to do

tive, do not pressure refuel the helicopter. In

so could result in refuel manifold seepage

addition, if both float switches are inopera-

caused by fuel expansion.

tive for either main tank, the system must be

repaired before flight to prevent fuel cell

overpressure.

m. APU -

Start (refer to Chapter 8). Place APU

GEN switch to ON or apply AC external power.

(6) Open the flow control valve on the nozzle.

n. Operate the forward boost pump on either main

Check that fuel flow stops within

4 seconds. A small

tank for about two

minutes.

amount of fuel will continue to flow through the open

secondary ports.

o. Place APU GEN switch to OFF, APU switch to

OFF, or disconnect the external power.

(7) Set the ALL TEST switch to SEC OFF.

Check that fuel flow stops within 4 seconds. A small

2-223. Gravity Refueling. Perform the following

amount of fuel will continue to flow through the open

steps:

primary ports.

a. Be sure the helicopter is at least

50 feet from any

f. If all tanks are to be filled, set the ALL TEST

hangar or structure.

switch to FLOW. All tanks will now fill independently.

Rotate the FUEL QUANTITY selector switch, check-

b. Be sure the fueling vehicle is at least

10 feet from

ing each tank for proper fill and quantity. Shutoff valves

the helicopter.

in each tank will close and stop fuel flow as each tank

fills.

c. Electrically ground the helicopter as follows:

g. When refueling is complete, close the flow control

(1) Connect one end of an approved ground

valve.

cable to the aft landing gear eyebolt or to one of the

jacks on the side of the fuselage. Grounding jacks are

h. If tanks are to be partially or selectively filled, be

located at sta. 115 on the RH side and sta. 530 on the

sure to perform steps e.(6) and e.(7), then proceed as

LH side in the fuselage skin. Connect the other end to

follows:

a grounding rod or ramp ground point. Make sure the

(1) Set the six FUEL CELL SHUTOFF VALVE

cable has no broken strands and the clips are securely

TEST switches to PRI OFF.

attached to the cable and ground points.

2-90

TM 55-1520-240-10

(2) Make sure the fueling unit is grounded to the

b. Fuel hose from refueling source - Connect to aircraft

same ground rod or ground point as the helicopter.

single-point pressure refueling connection.

(3) Before opening the filler cap, ground the nozzle

c. Single-Point Pressure Refueling Hose Assembly -

to the ground jack directly above the fuel tank filler.

Unisex valve at the ERFS II tank - OPEN.

d. When the fuel is at the desired level, remove the

d. Manual FUEL/DEFUEL VALVE at each tank

nozzle. Secure the filler cap. Then, disconnect the nozzle

assembly - OPEN.

ground wire.

e. REFUEL STA switch located on the overhead FUEL

e. Remove the ground connection. If the helicopter is

CONTR Panel - ON.

to remain parked, do not disconnect the helicopter

ground.

REFUEL VALVE switch on the ERFS II Fuel Control

Panel OPEN. IN TRANSIT light will briefly illuminate.

2-223.1. ERFS II Refueling.

g. Refuel the ERFS II tanks. Fuel flow will automatically

Refueling the ERFS II tanks is performed by either single

stop when tanks are full.

point pressure refueling or gravity refueling.

h. FUEL QUANTITY switch - Set to 1, 2, 3, and TOTAL

WARNING

to confirm tanks and system contain desired fuel

quantities.

The manually operated fuel/defuel vent valve

on each tank must be placed in the closed

REFUEL VALVE switch - CLOSE. IN TRANSIT light

position following pressure refueling. Fail-

will briefly illuminate.

ure to do so could permit significant fuel leak-

age in the event of a crash and the vent self-

WARNING

sealing breakaway valve fails to actuate.

The manually operated fuel/defuel valve

must be placed in the closed position follow-

CAUTION

ing pressure refueling. Failure to do so could

If the fuel/vent valve is not opened, the tank

permit significant fuel leakage in the event of

cannot be pressure refueled.

a crash and the vent self-sealing breakaway

a. Single Point Pressure Refueling. The ERFS II tanks

valve fails to actuate.

are single point pressure refueled from a connection at the

Manual FUEL/VENT VALVE at each tank assembly

motorized gate valve. The motorized gate valve must be

– CLOSED.

open to pressure refuel and is controlled by the refuel

valve switch on the ERFS II fuel control panel located on

k. Single-Point Pressure Refueling Hose Assembly -

the forward most ERFS II tank installed. The fuel transfer

Unisex valve at the ERFS II tank - CLOSE.

hose is connected to the forward interconnecting ERFS II

Fuel hose from refueling source - Disconnect from

fuel manifold. Fuel from the transfer hose passes through

aircraft single-point pressure refueling connection.

the breakaway valve and the manual fuel/defuel valve to

the lower fuel/shutoff valve in the tank bottom.

m. Electrical ground - Disconnect electrical ground

from refueling source to the aircraft.

CAUTION

2-223.3. Gravity Refueling.

The operator must exercise caution to avoid

a. Electrical ground - Connect electrical ground from

ERFS II tank overflow during gravity refuel-

refueling source to aircraft.

ing. There is no automatic fuel flow shutoff.

b. Grounding Cable on each ERFS II tank - Check

b. Gravity Refueling. If pressure refueling of ERFS II

connection security.

tanks is not performed or prevented, each tank can also

be gravity filled through the gravity filler opening on the top

c. Filler Cap - Remove.

of each tank. To gravity fill, the crashworthy filler cap is

d. Service tank.

removed and external fuel source nozzle is inserted and

the tank is filled. Low pressure flow rates must be

CAUTION

maintained as venting of vapors bypass the filler opening

The operator must exercise caution to avoid

and the fuel/defuel vent valve is closed during this

ERFS II tank overflow during gravity refuel-

operation. Because fuel is not entering the tank through

ing. There is no automatic fuel flow shutoff.

the fuel/defuel line, the high level shutoff valve has no

effect stopping the fuel flow into the tank.

e. FUEL QUANTITY switch - Set to 1, 2, 3, TOTAL to

confirm tanks and system contain desired fuel quantities.

2-223.2. Single Point Pressure Remodeling.

(Will indicate only when aircraft power is applied).

a. Electrical ground - Connect electrical ground from

Filler Cap - Replace.

refueling aircraft. Check that the ground wire from each

ERFS II tank is connected to an aircraft ground

g. Electrical ground - Disconnect electrical ground

receptacle.

from refueling source to aircraft.

Change 14

2-90.1

TM 55-1520-240-10

main fuel tanks through the aircraft fuel system quick

2-226. Transmission Oil System.

disconnect fittings in the left and right side cargo

Service the forward transmission, engine/combining

compartment at STA 380. During transfer, the roll-over

transmission, and aft transmission as follows:

vent valve in each ERFS II tank allows venting and

a. Access to oil filler and location of sight gage of each

equalization of tank pressure above 5 psi from thermal

transmission (fig. 2-53) are as follows:

expansion, contraction, and barometric pressure

(1) The oil filler and sight gage for forward transmis-

changes in the bladders. The high level fuel shutoff valves

sion are accessible within the hinged fairing on the right

in the tanks prevent overfilling. The metallic float and ball

in the roll-over vent valve prevents fuel from escaping

side of the forward pylon. The filler neck is in the top for-

ward area of the transmission. The sight gage is located

should the tank become inverted in a roll-over and

prevents slosh from uncoordinated flight from leaking to

in the bottom area below the filler neck; it can be viewed

the overboard vent lines. To transfer fuel from the fARE

from above and can also be seen through a viewing port

in the canted bulkhead at sta. 95 above the pilots seat.

system, fuel is pumped from the ERFS II tanks by the

FARE pump. The manually operated fuel/defuel valve

(2) The oil filler and sight gage for aft transmission is

must be in the open position for the FARE transfer.

on forward right side of the transmission sump. It is acces-

sible from the cargo ramp area.

2-224. Engine Oil System.

(3) The common oil filler for the combining transmis-

The engine oil tank an oil quantity indicator are an integral

sion and both engine transmissions is on the combining

part of the engine (fig. 2-53). Service either engine oil

transmission oil tank. It is accessible within the fairing of

system as follows:

aft pylon leading edge.

a. If the engine has not been operated in the preceding

b. Refer to DA Form 2408-13 and table 2-3 for the type

24 hours and the oil level is low, run it and then recheck

of oil to use. Under normal conditions, the transmissions

the oil level. Otherwise, an inaccurate oil level may be

shall be serviced with one type of oil only. If one type of oil

indicated.

is in a transmission and that oil is not available, the other

b. Check oil level by looking through the grilled opening

type may be used in an emergency.

on the left side of the engine cowling at the 9 o’clock

NOTE

position.

To prevent overfilling the forward, aft, and en-

c. If the indicator shows less than full, open the oil filler

gine/combining transmissions, check oil level

access panel on the forward top side of the engine cover.

within 30 minutes of shutdown. If the transmis-

sions have been shut down for more than 30

d. Refer to DA Form 2408-13 and table 2-3 for the type

minutes, run the helicopter for a minimum of 5

of oil to use. Under normal conditions, engines shall be

minutes to verify oil level before servicing.

serviced with one type of oil only. If one type of oil is in an

NOTE

engine and that oil is not available, the other type may be

To prevent overfilling the forward and aft trans-

used in an emergency.

mission, check oil level after the aircraft has

e. Remove the filler cap. Fill the tank with oil until the

been shut down for 30 minutes.

indicator shows full. Do not overfill tank.

c. Fill the forward transmission, engine/combining and

Install the filler cap. Close both access panels.

aft transmissions to the FULL mark next to each sight

gage.

2-225. APU Oil System.

2-227. Hydraulic Systems Servicing.

Service the APU as follows:

2-228. Hydraulic Systems Fluid Servicing. The util-

CAUTION

ity systems and both flight control hydraulic systems are

Do not use the APU drip pan as a handhold.

serviced by a common fill module on the right side of the

Damage to equipment will result.

helicopter above the ramp (fig. 2-53). The fluid level indi-

a. Remove the filler cap from the left side of the APU

cators are on the MAINTENANCE PANEL above the fill

(fig. 2-53).

module. One indicator is for both flight control hydraulic

CAUTION

systems. The other indicator is for the utility system. Di-

Do not overfill. Damage to the APU can result

rect level checks can also be made from the reservoir pis-

from overfilling.

ton rods. Service any system as follows:

b. Add oil to the APU oil tank until the level reaches the

a. Check the sight gage on the fill module reservoir for

FULL mark on the sight gage. Under normal conditions,

fluid level. If fluid cannot be seen on the sight gage, fill the

the APU shall be serviced with one type of oil only. If one

reservoir.

type of oil is in an APU and that oil is not available, the

b. Check the fluid level in the flight control reservoirs by

order type may be used in an emergency.

selecting each system at the FLT CONTR switch on the

c. Reinstall and check security of the filler cap.

MAINTENANCE PANEL. Then press the LEVEL CHECK

Change 14

2-91

TM 55-1520-240-10

CHECK switch. Check the fluid level in the utility

(3) Note precharge on accumulators and ensure

reservoir by pressing the LEVEL CHECK switch.

is within limits as per figure 2-54.

c. Turn the system select valve to the position for the

(4) If servicing is required, refer to TM 55-1520-

system to be serviced.

240-23.

d. Using the handpump on the fill module, pump

b. The power steering and swivel lock accumulator is

fluid into the system until the fluid in the reservoir is at

located on the right side of the cabin, in the cargo ramp

the FULL mark. Keep the sight gage on the fill module

area. Determine accumulator precharge as follows:

full of fluid by adding fluid to the reservoir as required.

e. Turn the system select valve to OFF.

NOTE

An alternate method is to apply external

2-229. Hydraulic Systems Accumulator Precharge.

power to the helicopter and cycling the

Figure 2-54 depicts the relationship between proper

STEERING CONTROL SWIVEL STEER

accumulator precharge and ambient temperature. To

switch on the center console from LOCK to

check that an accumulator is properly precharged, read

UNLOCK several times.

free air temperature from the FAT gauge. Enter the

bottom of the chart at the indicated temperature and

move vertically to the pressure indicated on the accu-

(1)

Repressurize the accumulator by starting the

APU and placing the APU GEN switch to

mulator pressure gage. If the indicated pressure is

within the minimum and maximum limits, the accumu-

ON.

lator is properly precharged. If the indicated pressure is

(2)

Place the HYD BRK STEER isolation switch

not within limits, refer to TM 55-1520-240-23 to service

on the overhead switch panel to OFF. Cycle

the accumulator.

the STEERING CONTROL SWIVEL

STEER switch on the center console from

2-230. Flight Controls Hydraulic Systems Accu-

LOCK to UNLOCK approximately six times.

mulators. The No. 1 flight control system accumulator

is within the forward transmission fairing, on the right

(3)

Note precharge on accumulator and ensure

side. The No. 2 system accumulator is within the aft

precharge is within limits as per figure 2-54.

pylon, on the right side. Determine either accumulator

(4) If servicing is required, refer to TM 55-1520-

precharge as follows:

240-23.

a. Access to the respective accumulator.

c. The brake accumulator is located within the aft left

b. Note precharge on accumulator and ensure is

side of the forward transmission fairing. Determine

within limits as per figure 2-54.

accumulator precharge as follows:

c. If servicing is required, refer to TM 55-1520-240-

(1) Repressurize the accumulator by pressing the

23.

brakes approximately four times or until it

becomes hard to apply the brakes.

2-231. Utility System Accumulators. There are five

accumulators in the utility hydraulic system. They pro-

(2) Accumulator precharge should read between

vide pressure to start the APU, operate the power

600 to 850 psi.

brakes and swivel locks, and maintain line pressure

(3) If servicing is required refer to TM 55-1520-

throughout the system.

240-23.

a. The APU start accumulator is the largest in the

helicopter. It is mounted overhead in the cabin at the

2-232. Ground Handling (Towing).

right of the aft transmission sump. The APU start

Refer to TM 55-1520-240-23.

module accumulator is located aft and to the right of the

APU start accumulator. The utility reservoir pressuriza-

2-233. Parking.

tion (bootstrap) accumulator is located forward of the

No. 2 flight control accumulator in the aft pylon,

Park the helicopter as directed in the following steps:

accessible through the pylon right access panel. Deter-

a. Apply wheel brakes. Then, set the parking brakes.

mine accumulators precharge as follows:

b. Place chocks as required.

(1)

Repressurize the accumulator by turning the

handle on the UTILITY RESERVOIR RE-

CAUTION

PRESSURIZE valve to OPEN. The valve is

on the right side of the cabin, in the cargo

Failure to position blades properly can allow

ramp area.

a blade to hit the fuselage. This may damage

(2)

Press and hold the depressurization valve on

the fuselage and blade.

the APU start module accumulator until sys-

tem pressure is depleted. When the accumu-

c. Position rotary-wing blades 30° off centerline of

lator has been repressurized, return the han-

helicopter.

dle of the UTILITY RESERVOIR

REPRESSURIZE valve to NORMAL.

d. Unplug the battery after the last flight of the day.

2-92

55-1520-240-10

e. Lock all doors and hatches.

k.Rotor hub protective cover (2 ea).

f. Moor the helicopter (refer to TM 1l.Heater exhaust protective cover.

2-234. Mooring.

m. Heater inlet cover.

Refer to TM 1-1500-250-23. The methods of mooring vary

with intensity of winds. Table 2-72-236.oHelicoptersSecurityc(Typical).ry

precautions to be taken pertaining to these conditions.

The helicopter is equipped with door lock se

(fig. 2-56). These devices prevent interior

Table 2-7. Mooring Data

helicopter by unauthorized persons. Install

follows:

WIND SPEED

TIEDOWN REQUIREMENT

a. Make sure the ramp is full up. Install

0 to 39 mph

Two forward blades tied down.

through the ramp controls access door latch

39 to 65 mph

Fuselage and blades tied dfas

tener to the bracket. Make sure the warnin

Over 65 mph

Evacuate helicopter from tvisibl

or store helicopter in hangar.

b. Close the lower rescue hatch door. If t

be closed, secure the utility hatch to a ti

2-235. Protective Covers.

cargo strap.

The following protective covers should be stowed in the

helicopter (fig. 2-55). They are used asc. Secure the release straps of the two

helicopter is parked or moored.

hatches and the cargo door escape hatch wit

clamps. Make sure the clamps are located as c

Engine (LH) inlet cover.

release grommet as possible. Make sure the warn

Engine (RH) inlet cover.

ers are readily visible.

Engine outlet cover (2 ea).

d. Install lock pins through the pilot’

Hydraulic cooler exhaust cover.

window latches. Then, insert the quick-releas

the bracket on the floor and into the door la

Pitot tube covers (2 ea).

sure the warning streamers are readily visibl

Aft transmission cooler and APU exhaust cover.

e. Install left forward latchable escape ha

Transmission and hydraulic cooler intake.

f. Close the cabin doors. Install the b

h.Transmission and hydraulic cooler exhaust (LH and

padlock.

RH).

i. Transmission and hydraulic cooler inlet (aft pylon).

j. Cockpit enclosure protective cover.

2-94

Change

55-1520-240-10

CHAPTER

AVIONICS

SECTION I GENERAL

3-1. Description.

3-3. Avionics Power Supply.

The avionic systems in the CH 47D helicopters consist of the

communications equipment providing HPower to operate the avionic systems is supp

VHF-FM, and UHF-AM communications. The and No. 2 DC buses, the DC essential bus, an

equipment includes LF-ADF, VOR ILS, Mar115-volt and 26-volt AC buses (Chapter 2)

Doppler/GPS, and Omega. VHF-FM homing is provided

through the AN/ARC-201 FM communication radio.

Transpondeequipmentconsists

of IFF

The No. 1 VHF AM/FM, interphone and UHF

receiver-transmitter with inputs fromoperated by selecting the BATT switch to O

equipment, the APU ge

altimeter for altitude encoding. Absolutremaining avionicsed

by a radar altimeter. For mission avionicmain helicopter generators. must be operat

power must be connected. All circuit brea

Chapter 4, Mission Equipment.

3-2. Avionics Equipment Configuration.

Equipment configuration in the CH-47D helicopter is listed

in table 3-1.

Change

3-1

55-1520-240-10

Table

3-1.

Communications/Navigation Equipment

FACILITY

DESIGNATION

USE

LOCATION

INTERPHONE

C-6533/ARC

INTERCOMMUNICATIONS BETWEEN

THREE INTERPHONE CONTROLS ON

CREWMEMBERS AND RADIO CONTROLONSOLE, THREE INTERPHONE

CONTROLS IN CABIN

UHF RADIO

AN/ARC-164

TWO-WAY UHF-AM COMMUNICATIONCONTROL ON CONSOLE

(INCLUDES R/T)

VHF AM/FM

AN/ARC-186

TWO-WAY VHF AM/FM

CONTROL ON CONSOLE

RADIO

COMMUNICATIONS

(INCLUDES R/T)

VOICE SECURITY

TSEC/KY-58

TWO-WAY CLEAR OR SECURE VOICECONTROL ON CONSOLE

EQUIPMENT

COMMUNICATION FOR NO. 1 VHF/FM

RADIO

TSEC/KY-75

COMSEC

CONTROL ON CONSOLE

(IF INSTALLED)

TSEC/KY-100

SECURE VOICE AND DATA

CONTROL ON CONSOLE

COMMUNICATION. OPERATIONAL

(IF INSTALLED)

WITH NARROW AND WIDE BAND

RADIOS (HF, VHF, UHF, SATCOM)

VHF NAVIGATION

AN/ARN-123

PROVIDES VOR BEARING AND COURCONTROL ON CANTED CONSOLE

AND INSTRUMENT

INFORMATION, ILS LOCALIZER, GLIDE

LANDING SYSTEM

SLOPE, AND MARKER BEACON

INDICATIONS

DIRECTION

AN/ARN-89

AUTOMATIC OR MANUAL DIRECTIOCONTROL ON CANTED CONSOLE

FINDER SET

FINDING AND HOMING

GYROMAGNETIC

AN/ASN-43

PROVlDES HEADING INFORMATIONCONTROL ON OVERHEAD SWITCH

COMPASS SET

FREE GYRO OR MAGNETIC MODES

PANEL

DOPPLER

AN/ASN-128

PROVIDES WORLDWIDE NAVIGATION

CONTROLS ON CANTED CONSOLE

NAVIGATION SET

CAPABILITY WITHOUT USE OF

GROUND FACILITIES

DOPPLER GPS

AN/ASN-128B

PROVIDES WORLDWIDE NAVIGATION

CONTROL ON CANTED CONSOLE

NAVIGATION SET

CAPABILITY WITHOUT USE OF

(INCLUDES DISPLAY)

GROUND FACILITIES

TRANSPONDER

AN/APX-100

RADAR IDENTIFICATION AND

CONTROL ON CANTED CONSOLES

SYSTEM

TRACKING

OMEGA NAVIGA-

AN/ARN-148

PROVIDES NAVIGATION CAPABILICONTROL ON CONSOLE

TION SYSTEM

USING GROUND FACILITIES

HIGH FREQUENCY

AN/ARC-199

LONG RANGE TWO-WAY

CONTROL ON CONSOLE

RADIO SET

COMMUNICATIONS

HIGH FREQUENCY

AN/ARC-220

LONG RANGE TWO-WAY

CONTROL ON CONSOLE

RADIO SET

COMMUNICATIONS WITH ALE AND

ECCM

VHF-FM RADIO

AN/ARC-201

TWO-WAY VHF-FM COMMUNICA-

CONTROL ON CONSOLE

TIONS AND HOMING

3-2

Change

TM 55-1520-240-10

SECTION II COMMUNICATIONS

CONTROL/

3-4. Interphone System (C-6533/ARC).

INDICATOR

FUNCTION

The interphone system is a multi-station intercommu-

2- UHF radio

nication and radio control system for control of voice

radio communication. It also monitors the output of

3- No. 2 VHF AM/FM

radio

navigation radio receivers and warning tones from IFF

4- HF radio

and radar warning sets. The basic components of the

5- Not used

interphone system are six control panels (fig. 3-1).

AUX - VOR/Localizer

There is one panel each for the pilot, copilot, troop

NAV - direction finder

commander, the two gunners stations, and flight engi-

OFF disables associated

neer. In addition, there is an interphone station for the

audio input to headset.

hoist operator and two external interphone receptacles.

ON radio enables associ-

Power for the system is supplied by the DC essential bus

ated input to headset.

through the COMM INTPH LH and COMM INTPH

RH circuit breakers on the No. 1 and No. 2 PDP.

HOT MIKE

Two position toggle switch

Switch Position

enables hands-free opera-

tion (PIT/foot switch op-

3-5. Controls and Function, Interphone Control

eration not required) of

(C-6533/ARC). (fig. 3-2)

headset microphone for

CONTROL

interphone only.

INDICATOR

FUNCTION

OFF

Hands-free operation dis-

abled. PTT/foot switch

Function Selector Switch

Five position rotary switch

operation required for

Position

used to select interphone

operation.

operating mode.

HOT MIKE

Hands-free operation en-

ICS

Connects headset-

abled.

microphone to interphone

system.

NOTE

Connects headset-

Switch settings are not necessary to receive marker

microphone to No. 1 VHF

beacon, radar warning, and IFF audio tones.

FM or No. 1 VHF

Press to talk (PTT)

Two or three position

AM/FM radio set.

Switches Position

switches used to enable

Connects headset-

the microphone side of

microphone to UHF radio

the interphone system

set.

when operator is speak-

Connects headset-

ing. These switches are

microphone to No. 2 VHF

described in detail below.

AM/FM radio set.

Pilot/Copilot Trigger PTT

Three position PTT

Connects headset-

Switch (on pilot and copi-

switch. Off disables micro-

microphone to HF radio

lot cyclic stick) Position

phone (not pressed) en-

set.

ables headset.

Not used.

Interphone

Enables microphone

(First detent)

transmission to all inter-

NOTE

phone stations, regardless

Pilot/Copilot can transmit on all four transmitters.

of function switch settings.

Troop Commander can transmit on the HF and

Radio transmit

Enables microphone

VHF FM transmitters only. Gunners and Flight En-

(Second detent)

transmission over radio

gineer cannot access any transmitters.

set selected by control

panel function switch.

Receiver Switches 1-5,

Seven two position toggle

Pilot’s/Copilot’s Foot

Two position PTT switch.

AUX, and NAV Position switches used to select-

Switches (on cockpit floor

headset audio input as

next to heel slide) Posi-

follows:

tion

1- No. 1 VHF FM or No.

1 VHF AM/FM radio

3-3

TM 55-1520-240-10

CONTROL/

figure shows the maximum antenna configuration. All

INDICATOR

FUNCTION

antennas illustrated may not appear on all helicopters.

Off

Released position; dis-

3-7. UHF-AM Have Quick II Radio (AN/ARC-164).

ables microphone.

The UHF Have Quick II (HQ II) radio (AN/ARC-164)

Talk

Depressed position; en-

ables headset microphone.

is located on the center console. It is capable of

providing normal and ECCM, anti-jam (AJ) two-way

Hoist Control PTT Switch

Two position PTT Switch.

voice communications in the band from 225.000 to

(on hoist control grip)

399.975 MHz in 25 kHz increments. The HQ II is

Position

capable of operating with the Basic HAVE QUICK

Off

Released position; dis-

radio,. It also provides 20 preset frequencies and will

ables microphone.

monitor and transmit on a permanent guard channel

Talk

Depressed position; en-

(243.000 MHz). When in the AJ mode preset 20 is

ables headset microphone.

restricted to AJ operations. The usual operating mode

HOT MIKE switch on

Three position toggle

for the radio set is the normal mode where the radio

HOIST OPERATORS

switch selects hoist opera-

uses 1 of 7,000 frequencies. Power for the UHF-AM

PANEL (Chapter 4)

tor’s interphone operating

Have Quick II radio set is supplied by the 28 volt

mode.

essential bus through the COMM UHF AM circuit

OFF

Requires operation of

breaker on the No. 1 PDP.

PTT switch for interphone

There are presently three configurations of the AN/

communications.

ARC 164 UHF/AM radio. The following paragraphs

HOT MIKE

Operation of PTT switch

identify the the visual differences in their configuration.

not required for inter-

phone communications.

a. AN/ARC 164, UHF/AM Basic (not modified for

Have Quick) 100MHz selector for the hundreds digit

MOM ON

Operation of PTT switch

only has a 2 and a 3 position.

not required for inter-

phone communications.

b. AN/ARC 164 UHF/AM Have Quick I (capable of

(Spring loaded to OFF

single WOD entry only) Has a four position selector for

position when released.)

the hundreds digit, A,2,3, and T. Does not have EMB

Gunner’s Foot Switch

Two position pressure

label ajacent to the Pre-set channel selector.

Position

sensitive switch mounted

c. AN/ARC 164 UHF/AM Have Quick II. Same as b.

in moveable floor mat.

above, but includes EMB label ajacent to the preset

Off

Released position; dis-

channel selector.

ables microphone.

Reverse compatible communications between HQ II

Depressed position; en-

and HQ I radios in the AJ mode, is accomplished by

ables microphone.

either, entering a single WOD or selecting the appro-

priate MWOD and net number with a suffix 00.

3-7.1. Anti-Jam Mode.

The AJ mode uses a frequency hopping scheme to

change the frequency many times per second. This

makes it difficult for the enemy to jam the frequencies

since knowledge of the frequencies being used by the

pilot are unavailable. Because the particular frequency

used at any instant depends on the precise time-of-day

(TOD), all participating UHF-AM Have Quick II ra-

dios must have clocks which are synchronized. In addi-

tion, all participating radios must have the same word-

of-day (WOD) and net number data when in the AJ

mode.

3-7.2. Word-of-Day. The WOD programs the fre-

Figure 3-2. Interphone Control (C-6533/ARC)

quency hopping rate and pattern. Without it, the radio

cannot function in the AJ mode. A WOD is made up of

3-6. Antenna System.

a maximum of six WOD segments plus a date code. The

Have Quick II radios are capable of storing up to six

Antennas used for avionics communications and elec-

WODs, thus allowing for multi-day use of the radio set.

tronic systems equipment are shown in figure 3-3. This

This technique is known as multiple word-of-day

Change

3-5

55-1520-240-10

1. Glide slope

9. ADF loop and sense antennas

2. Radar warning

10.UHF-AM

3. HF ARC-199 antenna

11. VHF AM/FM (typical top and bottom)

4. VHF navigation

12.FM homing

5. Radar warning

13. Doppler navigation

6. IFF

14.Radar warning

ntenna

7. ECM antennas

15. Radar altimeter

8. Marker beacon

16.Omega antenna

17. Omega temperature probe

Figure 3-3. Antenna Locations

(MWOD) loading. The basic HAVE QUICKFUNCTIONio allowFREQUENCY

USE

loading a single WOD, in volatile memory.

logged for an en-

Four operating modes are used within the radio set to

tered date code.

initiate various Have Quick (HQ) proMWOD loadun220.025.

Enables the load-

They are accessed via preset 20 with the frequencies listed

ing of MWODs.

in Table 3-1.1. The functions are Operate/verify, MWOD

MWOD Erase

220.050

Enables the pilot

load, MWOD erase, and frequency managed training (FMT)

to completely

frequency load.

erase the non-

volatile memory

Table 3-1.1.

Have Quick II Additional Functions

containing the

Frequency and USE.

MWODs.

FUNCTION

FREQUENCY

USE

FMT frequen

220.075

Enables the load-

load

ing of training

Operate/veri

20,000

Places the radio

frequencies.

in the normal op-

erating mode anMWOD data is stored in nonvolatile memory

provides for tradio set. Seven memory locations are avail

verification oMWOD

with the capability of storing a max

MWOD

MWODs within the radio set. The channel

3-6

Change

TM 55-1520-240-10

the manual frequency selectors, and the tone button are

Table 3-1.2 Net selection (Continued)

utilized to load the required segments for each MWOD.

TRAINING

Channel positions 20-14 are used to facilitate the load-

ing of MWOD segments. A minimum of one WOD must

00 - Basic HAVE QUICK Training

be stored for the unit to be functional in the AJ mode.

- HAVE QUICK II Training

Channel position 14 is used for day-of-month informat-

50/75 Not Used- Interrupted Fault Tone

ion (date code). The date code is represented by

frequency 3AB.000 MHz in which AB is the day of the

Table 3-1.3 Net Type, Quantity, and Frequency Range

month. For example; if today’s date is the 15th of the

month, the date code entry would be 315.000 MHz.

Types of Nets

Quantity

Range of Nets

Channel position 1 is used for entering the current

operational date when HQ II TOD is not available. The

format used to enter the operational date is the same as

Basic HQ Training

A00.000 - A000.400

the date code format.

Basic HQ Tactical

1000

A00.000 - A01.500

HQ H Training

A00.025 - A01.525

When the radio is turned off or power is lost after entry

HQ II Tactical

1000 A00.0XX-A99.9XX

of MWOD and date code, the data is not lost; therefore,

the information remains intact until manually changed

or erased. The six most recently entered MWOD’s are

NOTE

retained. If a MWOD with a duplicate date is entered,

Any selection of a net number outside the-

the new entry takes precedence.

range indicated, for each type of net, will

After the MWOD information is entered, the pilot

result in the invalid net number warning

would proceed to obtain the TOD. Operational date

tone.

information is part of the HQII TOD message. If HQII

TOD message is unavailable, the pilot must manually

enter the operational date so the radio can select the

3-7.5. Conferencing. In the AJ mode, the radio has

proper MWOD. If power is lost, operational date is lost

the capability to receive and process two simultaneous

and must be reentered.

transmissions on the same net. This conferencing capa-

bility is selected by the hundredth and thousandth digits

3-7.3. Time-of-Day. The TOD is essential for com-

of WOD segment 2, loaded using channel position 19

municating in the AJ mode which allows frequency-

and is disabled when operating in the secure speech

hopping at the same instant in time. Reception and

mode.

transmission of the TOD is possible in normal and AJ

modes. The first TOD reception must occur in the

In a conference net, the second transmitting radio will

normal mode.

automatically shift its transmission frequency by 25 kHz

The radio automatically accepts the first TOD message

when it monitors a transmission on the primary net

once the predesignated frequency for TOD transmis-

frequency. The wide band receiver will monitor both

sion has been entered and the T position of the

transmissions without the interference normally associ-

hundredth megahertz selector has been momentarily

ated with two radios transmitting on the same frequency

selected and released. Subsequent messages are ignored

simultaneously. Three simultaneous transmissions will

unless the pilot enables the radio to receive a new/

create garbled reception.

updated TOD. The TOD contained in a radio may also

be sent to other radios similarly equipped.

3-8. Controls and Function, UHF-AM Have Quick

II Radio (AN/ARC-184). (fig. 3-4)

3-7.4. Net Number. The net number enables multi-

ple station nets to operate simultaneously on a non-

CONTROLS/

interfering basis in AJ mode, while sharing a common

INDICATOR

FUNCTION

WOD and TOD. The net number begins with the letter

A and is followed by three digits from 000 to 999. The

Function Select Switch

Four position rotary

last two digits of the display designate how the radio is

switch used to select radio

to function and/ or the frequency hopping table being

operating mode.

used (Table 3-1.2). Net number availability is depend-

OFF

Power to set is disabled;

ent on the operational mode of AJ and is depicted in

radio set inoperative.

Table 3-1.3.

MAIN

Radio set can be used to

Table 3-1.2 Net selection

transmit and receive;

guard receiver inopera-

TACTICAL

tive.

BOTH

Radio set can be used to

00 - Basic HAVE QUICK

transmit and receive;

- HAVE QUICK II NATO Hopset

guard receiver operates.

50 - HAVE QUICK II non-NATO Hopset

- Not Used-Interrupted fault Tone

ADF

Not used.

Change

3-7

TM 55-1520-240-10

CONTROLS/

INDICATOR

FUNCTION

VOL

Rotary control used to

adjust radio output vol-

ume.

SQUELCH Switch

Two position toggle switch

to select radio squelch

mode.

OFF

Squelch is disabled.

Squelch is enabled.

Frequency Mode Selector

Three position rotary con-

trol used to select fre-

quency tuning mode.

MANUAL

Permits manual frequency

selection using frequency

controls.

PRESET

Permits selection of preset

channel frequencies in

radio set (maximum of 20

channels).

GUARD

Automatically disables the

anti-jam mode and tunes

Figure 3-4. UHF-AM Have Quick II Radio (AN/

radio set to guard channel

ARC-764)

frequency (243.000 MHz).

Frequency Selectors

Five rotary controls used

CONTROLS/

to select radio operating

INDICATOR

FUNCTION

frequency or state.

TONE

Momentary contact

100 MHz Control

Four position rotary con-

switch. Pressing the

(A-3-2-T)

trol switch.

TONE switch when in the

Selects anti-jam mode.

normal mode enables a

Hundreds digit of desired

1020 Hz tone on the se-

lected frequency, unless

frequency while in the

normal mode.

TOD has been accepted

in which case a1667 Hz-

Hundreds digit of desired

tone is heard prior to the

frequency while in the

1020 Hz tone. When A-3-

normal mode.

2-T switch is in A, it en-

Momentary spring-return

ables TOD transmission

position which enables the

followed by a 1020 Hz

radio to accept a new

tone on the selected fre-

TOD for up to one

quency. When A-3-2-T

minute after selection.

switch is in T, it initiates

Also used in conjunction

the emergency startup of

with the tone button in

the TOD clock. When in

the emergency startup of

the load mode, Pressing

the TOD clock when

the TONE switch with

TOD is not available from

channels 1, 14, or 15

external sources.

through 20 selected in the

10 MHz Control

Ten position (0 through

manual mode enters the

rotary control used to se-

MWOD data into non-

lect second digit of oper-

volatile memory. Pressing

ating frequency. When in

the TONE switch when in

AJ mode, it selects the

the erase mode, erases all

first digit of net number.

MWOD data from non-

volatile memory.

3-8

Change 3

TM 55-1520-240-10

CONTROLS/

b. Presetting Channels. Perform the following steps

INDICATOR

FUNCTION

to preset a channel to a desired frequency.

(1)

Set the Frequency Mode Selector to PRE-

1 MHz Control

Ten position (0 through 9)

SET.

rotary control used to se-

lect third digit of operat-

(2)

Use the manual frequency selector switches

ing frequency. When in

to select the frequency to be placed in mem-

AJ mode, it selects the

ory.

second digit of net num-

(3)

Turn the preset channel control switch to the

ber.

desired channel number.

0.1 MHz Control

Ten position (0 through 9)

rotary control used to se-

(4)

Raise the cover under the channel card. Press

lect fourth digit of operat-

and release the PRESET switch. Close the

ing frequency. When in

cover.

AJ mode, it selects the

(5) Using a soft lead pencil, record the frequency

third digit of net number.

selected for the channel number on the card

0.025 MHz Control

Four position rotary con-

provided.

trol used to select fifth

c. Stopping. Function switch - OFF.

and sixth digits of operat-

ing frequency. Operates in

3-9.1. Anti-Jam Operation - UHF-AM Have Quick

0.025 MHz increments.

II Radio. The following steps provide AJ operating

When in the AJ mode, it

procedures.

selects the appropriate fre-

quency table within the

a. MWOD Loading.

radio net.

(1)

Perform paragraph 3-9 Starting steps a(1)

and a(2).

Frequency Display

Six digit display

(200.00

(2)

Channel selector switch - Set to 20.

through 399.975) displays

selected radio operating

(3)

Frequency mode selector switch - PRESET.

frequency.

(4)

Frequency selector switches - Set

220.025

Channel Selector

Used to select and display

MHz.

any of the 20 preset radio

(5)

PRESET switch

- Press. Radio is now pro-

frequency channels.

grammed to accept MWOD.

Displays selected preset

(6)

Frequency mode selector switch - MAN-

channel.

UAL.

PRESET Switch (Under

Momentary contact

channel/frequency card)

switch, when depressed

(7)

Frequency selector switches - Enter first

causes selected radio fre-

WOD segment.

quency entered on fre-

(8)

TONE switch

- Press. First WOD segment

quency display to be

is now loaded to the nonvolatile memory of

stored in channel indi-

the radio - Listen for BEEP.

cated on channel display,

(9)

Channel selector switch - Set to 19.

in normal operation.

(l0)

Frequency selector switches - Enter sec-

3-9. Normal Operation - UHF-AM Have Quick II

ond WOD segment.

Radio. The following steps provide operating proce-

(11)

TONE switch - Press.

dures.

(12)

The remaining four WODs can be loaded in

a. Starting.

a similar fashion by dialing the next lower

(1)

Interphone control panel - Set switches as

preset channel, selecting the next WOD

follows:

segment. After entering last segment, listen

for a double (3125 Hz) beep.

(a) Receiver 2 switch - ON.

(13)

Channel selector switch - Set to 14.

(b) Function select switch - 2.

(14)

Frequency selector switches - Enter date

(2)

Function switch - MAIN or BOTH.

code.

(3)

Mode selector

- As required.

(15) TONE switch

- Press. At this time, one

complete WOD with its corresponding date

(4)

SQUELCH switch

- As required.

code has been entered to the nonvolatile

(5) VOL control

- As required.

memory.

Change 3

3-8.1

TM 55-1520-240-10

(16)

Additional WODs can be loaded by repeat-

(6) TONE switch

- Press. All MWODs are now

ing steps (5) through (15). Once WODs

erased.

have been entered, today’s operational date

d. Training Frequency Load.

must then be entered.

(1)

Channel selector switch - Set to 20.

(17)

Channel selector switch - Set to 1.

(2)

Frequency mode selector switch - PRESET.

(18)

Frequency selector switches - Enter oper-

ational date.

(3)

Frequency selector switches - Enter 220.075

MHz.

(19) TONE switch - Press.

(4)

PRESET switch - Press.

b. Operate/Verify Modes.

(5)

Frequency mode selector switch - MAN-

(1) Operate Mode.

UAL.

(a)

Frequency mode selector switch - PRE-

(6)

Frequency selector switches - Enter desired

SET.

training frequency.

Channel selector switch - Set to 20.

(7)

TONE switch

- Press. A single beep will be

(b)

heard.

(c)

Frequency

selector switches - Enter

220.000 MHz.

(8) The next frequency is loaded by entering the

next lower preset channel, selecting the next

(d) PRESET switch -

Press. Radio set is

training frequency, and pressing the TONE

now programmed to operate in either

switch. Up to 16 training frequencies may be

normal mode or anti-jam mode.

entered. Following this procedure.

(2) Verify Mode.

e. TOD.

(1) TOD Receive/Update.

NOTE

This verification test only checks for pres-

NOTE

ence of a WOD with the corresponding date

The first TOD message received within one

code. It does not check for the authenticity

minute of selecting T on the hundreds fre-

of the WOD segments entered.

quency selector switch will be accepted.

When communications are slightly garbled

but otherwise acceptable during AJ opera-

(a)

Channel selector switch - Set to 20.

tions, this is an indication of drift in TOD

Frequency mode selector switch - MAN-

synchronization. A TOD update should be

(b)

UAL.

performed.

selector switches - Enter

date code to be verified.

(a) Frequency selector switches or channel

selector switch

- Set to predetermined

TOD frequency.

NOTE

If a single beep is not present for a particular

(b) Hundreds frequency selector switch -

date code and the anti-jam mode is entered

Momentarily select T, then release. A

using that date, a constant warning tone will

momentary 1667 Hz tone will be heard

be heard signifying that the anti-jam mode

while receiving the TOD message.

initialization cannot be properly completed.

NOTE

The following step is not necessary if TOD

(d) Channel selector switch - Set to 19, then

message is being transmitted continuously

back to 20. A single beep will be heard if

on the predetermined TOD frequency; for

a WOD with the date code in step (c) is

example, continuous TOD message is being

present.

transmitted from a satellite.

c. Erase Mode.

(1)

Channel selector switch - Set to 20.

the net.

(2)

Frequency mode selector switch - PRESET.

(2) TOD Send.

(3)

Frequency selector switches - Enter

220.050

(a) Frequency selector switches or channel

MHz.

selector switch - Set to predetermined

(4)

PRESET switch - Press.

TOD frequency.

(5)

Frequency mode selector switch - MAN-

(b) TONE switch -

Press. A momentary

UAL.

1667 Hz tone will be heard, when the

3-8.2

Change 3

TM 55-1520-240-10

TOD message is transmitted, followed by

by the HSI MODE SELECT panel, steering informa-

a 1020 Hz tone until switch is released.

tion will be shown by the course deviation indicator;

homing signal strength will be shown by the glideslope

(3) Emergency TOD Start-up.

deviation pointer; and homing signal adequacy warning

NOTE

will be shown by the glideslope failure and navigation

failure warning flags. The set operates on 28-volt DC

The emergency TOD start-up provides an

power: No. 1 set receives power from the DC essential

arbitrary TOD which is not synchronized to

bus through the COMM VHF NO. 1 AM/FM circuit

coordinated time. The radio set will not

communicate with any other Have Quick II

breaker in the No. 2 PDP; No. 2 set receives power from

radio set in AJ mode unless this new TOD is

the No. 1 DC bus through the COMM VI-IF NO.

transmitted to other radio sets.

AM/FM circuit breaker on the No. 1 PDP.

b. Antenna Select System

Three antennas are in-

(a)

Perform step a MWOD Loading

stalled as part of the AM/FM radio installation: a top

and bottom communications antenna and a FM homing

(b)

Perform step b (1) Operate Mode

antenna. Both AM and FM can be transmitted and

(c)

Hundreds frequency selector switch -

received over the same antenna but not at the same

Select T and hold while simultaneously

time. Antenna selection is controlled by the two position

pressing TONE switch. A 1667 Hz tone

VHF ANT SEL switch on the center instrument panel.

will be heard when the TOD is pro-

The normal switch position is down at the SYS 2 - SYS

grammed.

1 position. The No. 1 AM/FM set is connected to the

(d)

TONE switch - Release.

bottom antenna and the No. 2 AM/FM set is connected

(e) Hundreds frequency selector switch -

to the top antenna. If a water landing is to be made or

Release.

the bottom antenna is damaged, setting the switch up to

SYS 1- SYS 2 reverses the normal antenna connections

f. Anti-Jam Mode.

and connects the No. 1 AM/FM set to the top antenna

(1)

Perform paragraph 3-9 step a Starting.

and the No. 2 AM/FM set to the bottom antenna. This

ensures that secure voice is available through the top

(2)

Load MWOD - Refer to paragraph 3-9.1

antenna. Power to operate the system is supplied by the

step a MWOD Loading.

DC essential bus through the VHF ANT SEL circuit

(3)

Receive TOD -

Refer to paragraph 3-9.1

breaker on the No. 2 PDP.

step e(1) TOD Receive/ Update.

(4) Perform paragraph 3-9.1 step b(1) Operate

NOTE

Mode.

The antenna select system has no effect on

the FM homing antenna. The homing an-

NOTE

tenna (towel bar) is on the bottom of the

A steady 3125 Hz warning tone will be heard

fuselage aft of the cockpit (fig. 3-3) and is

connected to the FM set only.

when the anti-jam (A) mode is selected and

either the WOD is not in the nonvolatile

memory or the TOD has not been pro-

grammed.

3-11. Controls and Function, VHF AM/FM Radio

Set. (fig. 3-5)

(5) Hundreds frequency selector switch - A.

CONTROLS/

INDICATOR

FUNCTION

(6) Other frequency selector switches - Enter

net number.

Mode Select

Three position rotary

Switch

switch used to select radio

3-10. VHF AM/FM Radio Sets (AN/ARC-186).

operating mode. Power is

a. One or two VHF AM/FM radio sets (AN/ARC-

applied to radio in all po-

186) are installed: No. 1 set on the pilot side of the

sitions except OFF.

console, No. 2 on the copilot side. Each set provides

OFF

Power to set is disabled,

communications in the VHF AM and FM bands. The

radio is inoperative.

set operates in the following modes and frequency

ranges: AM reception between 108.00 and

151.975

Radio operates in the

MHz, AM receive and transmit between 116.000 and

transmit-receive mode.

151.975 MHz, and FM transmit, receive, and homing

Radio operates in the di-

from 30.000 to 87.975 MHz. Channel spacing is 25 kHz

rection finder mode.

in all bands. Up to 20 channels plus two guard channels

Frequency Control/

Four position rotary used

can be prestored in the set (removing power from the

Emergency Select

to select radio frequency

set does not affect stored channels). When the set is

Switch

tuning mode.

used for FM homing and selected for display on the HSI

Change 3

3-8.3

TM 55-1520-240-10

CONTROLS/

INDICATOR

FUNCTION

INDICATOR

FUNCTION

EMER AM

Radio is tuned to AM

Frequency Display

Display selected radio op-

Guard channel frequency.

crating frequency.

EMER FM

Radio is tuned to FM

WB/NB/MEM LOAD

Three position toggle

Guard channel frequency.

Switch (under channel

switch used to select radio

NAB

card)

operating band, and dur-

Allows manual tuning of

ing preset channel fre-

radio operating frequency.

quency loading.

PRE

Allows selection of any of

Places radio in NB (nar-

20 preset operating fre-

row band) operation.

quencies.

Places radio in WB (wide

VOL

Rotary control adjusts

band) operation.

radio output volume.

SQ DIS/TONE

Three position toggle

NOTE

Switch

switch used to select radio

Switch will remain in WB position unless otherwise

squelch operation.

instructed by radio set controller.

Normal (center

Preset squelch level is se-

position)

lected.

MEM LOAD

Momentary contact posi-

tion used with frequency

SO DIS

Squelch operation is dis-

controls and channel se-

abled.

lector to load preset chan-

TONE

Not used - maintenance

nels.

operation only.

Preset Channel Selector

Twenty position rotary

3-12. Normal Operation - AM/FM Radio Set. The

control used to select any

following steps provide operating procedures.

of 20 preset channel fre-

quencies.

a. Starting.

Display selected radio op-

(1) Interphone control panel - Set switches as

erating preset channel.

follows:

Frequency Controls

Four rotary controls used

to manually select radio

(a) Receiver 3 switch - ON.

operating frequency.

(b) Selector switch - 3.

10 MHz Control

Thirteen position

(03

through 17) rotary control

(2) VHF ANT SEL switch - SYS 2- SYS 1.

used to select first and

second digits of operating

b. Transmit-receive mode.

frequency.

(1)

Mode select switch - TR.

1 MHz Control

Ten position (0 through 9)

(2)

Frequency Control/Emergency Select Switch -

rotary control used to se-

As required. If greater receiver sensitivity

lect third digit of operat-

ing frequency.

is required, set the SQ DIS/TONE switch

to SQ DIS.

0.1 MHz Control

Ten position (0 through 9)

rotart control used to se-

(3) VOL control

- As required.

lect fourth digit of operat-

ing frequency.

0.025 MHz Control

Four position rotary con-

trol used to select fifth

and sixth digits (00

through 75) of operating

frequency in 0.025 MHz

increments.

3-8.4 Change

TM 55-1520-240-10

Figure 3-5. VHF AM/FM Radio Set (AN/ARC- 786)

c. Stopping. Mode select switch - OFF.

3-13. VHF/FM Radio Set (AN/ARC-201).

d. Presetting channels. Perform the following steps to

The AN/ARC-201 is located on the pilot instrument

preset a channel to a desired frequency.

panel and provides two-way frequency modulated

(FM)

narrow band voice communications.

(1)

Mode select switch - TR.

a. The following items form the airborne radio sys-

(2)

Frequency select switch - MAN.

tem.

(3)

Rotate the four frequency select switches

until the desired frequency is displayed.

ITEM

DESCRIPTION

(4)

Rotate the preset channel selector until the

Receiver-Transmitter Radio Panel Mounted

desired channel appears in the preset CHAN

(RT-1476)

indicator.

Amplifier (AM 7189)

(5)

Remove the snap-on cover.

(6)

Momentarily set the bandwidth WB, NB,

b. Essential Operational Technical Characteristics.

MEM LOAD switch to MEM LOAD. The

Except where specifically indicated otherwise, the fol-

preset frequency is now in memory.

lowing operational/ technical parameters are the mini-

(7)

Using a soft lead pencil, record the loaded

mum essential characteristics. Unless otherwise speci-

frequency opposite the channel number on

fied, they apply to each radio configuration.

the snap-on cover.

c. Frequency Range. The frequency range is 30 to

(8) Using the above procedure, preset any other

channelized in tuning increments of

channels and install the snap-on cover.

kHz. In addition a frequency offset tuning capability of

3-9

TECHNICAL MANUAL MAINTENANCE MANUAL FOR ARMY CH-47D HELICOPTER (1992) - page 4