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OPERATOR’S MANUAL FOR ARMY CH-47D HELICOPTER (EIC: RCD, 2003) - page 3

TM 1-1520-240-10

SECTION XIV. FLIGHT INSTRUMENTS

2-14-1. General.

wards the high end of the striped red-and-yellow band is

used for calibrating the indicator during bench test.

The following paragraphs contain information on the

flight instruments. Information on the navigation instru-

ments will be found in Chapter 3, Avionics. All other in-

struments directly related to one of the helicopter sys-

tems are found under the appropriate system heading in

this chapter. Refer to fig. 2-1-5 thru 2-1-14 for illustrations

of the instrument panels, canted and center consoles,

and overhead switch panel.

2-14-2. Cruise Guide indicator System.

The cruise guide indicator (CGI) system gives the pilot a

visual indication of actual loads imposed on critical com-

ponents of the helicopter dynamic system. The system

allows the pilot to achieve maximum helicopter utilization

under various conditions of payload, altitude, airspeed,

ambient temperature, and center-of-gravity. The system

consists of strain gages bonded to fixed links in the for-

ward and aft rotor controls, an indicator, a signal proces-

sor unit in the aft pylon, a signal conditioner unit in the

forward pylon, and interconnecting wiring. The system

measures alternating stress loads at each rotor and dis-

plays the larger of the two signals. Power to operate the

Figure 2-14-1. Cruise Guide Indicator

cruise guide indicator system is supplied by No. 2 DC bus

through the CRUISE GUIDE circuit breaker on the No. 2

PDP.

2-14-3. CRUISE GUIDE Indicator.

The CRUISE GUIDE indicator is on the pilot instrument

2-14-5. Airspeed Indicator.

panel (fig. 2-14-1). Three bands are colored green, yel-

low, and striped red-and-yellow. Refer to figure 5-2-1 for

There are two airspeed indicators located on the upper

limitations. Immediate corrective action must be taken to

left portion of the copilot and pilot instrument panel (fig.

reduce stress when in the red-and-yellow striped band.

2-1-7 and 2-1-9). The difference between dynamic pres-

This can be accomplished by lowering THRUST CONT

sure and static pressure as measured by the pitot static

lever, reducing airspeed, releasing back pressure on the

system is introduced into these instruments. Indicated

cyclic stick, or by reducing the severity of the maneuver.

airspeed is shown in knots.

2-14-4. CGI TEST Switch.

2-14-6. Altimeter.

The CGI TEST switch is on the pilot instrument panel, on

An AIMS altimeter is provided for the pilot (fig. 2-14-2).

the left side of the indicator (fig. 2-14-1). It is a three-posi-

In the term AIMS, the A stands for Air Traffic Control

tion switch spring loaded to center off position labeled

Radar Beacon System (ATCRBS), the I stands for identi-

FWD and AFT.

fication friend or foe (IFF), the M represents the Mark XII

identification system, and the S means system. A pneu-

NOTE

matic counter-drum-pointer type altimeter is installed for

Do not test the cruise guide system with rotors

the copilot. The pilots altimeter is a pneumatic counter-

turning. False indications will result.

drum-pointer type which is a self-contained unit consist-

When the switch is placed from the center position to

ing of a precision pressure altimeter combined with an

each test position, the pointer on the indicator should

altitude encoder.

indicate within the white test band. The white test band

Simultaneously, the display indicates and the encoder

indicates proper system operation.

transmits through the transponder the altitude of the heli-

When the test function is activated, circuits from the

copter. Altitude is displayed on the altimeter by a

strain gages to the indicator are tested. However, sepa-

10,000-foot counter, and a 100-foot drum. A single point-

ration of the bond of the strain gage to a link will not be

er indicates hundreds of feet on a circular scale with

detected by the test function. The narrow white line to-

50-foot center markings. Below 10,000 feet a diagonal

Change 3

2-14-1

TM 1-1520-240-10

warning symbol will appear on the 10,000 foot counter.

CAUTION

Power to operate the AIMS altimeter is supplied by the

No. 2 DC bus through the NAV AIMS ALT circuit breaker

If the baroset knob binds or sticks, do not

on the No. 2 PDP.

use excessive force to set the altimeter.

Excessive force can damage altimeter

A barometric pressure setting knob is provided to insert

gears, resulting in altimeter error. Settings

the desired altimeter setting in inches of Hg. A vibrator

can sometimes be made by backing off the

knob and turning at a slower rate.

a. Set the pilot’s altimeter to the field barometric

setting.

b. Check that the pilot’s altimeter indicates within ±

70 feet of field elevation. If the altimeter error is greater

than ± 70 feet, do not use the altimeter for IFR flight.

2-14-8. In Flight Operation - Altimeter.

Operate the AIMS altimeter function as follows:

a. Be sure the IFF set is on and set to the proper

code.

b. Be sure the altimeter is set to the local altimeter

setting.

c. Set the M-C (mode c) switch on the IFF control

panel to ON.

d. Check that the red CODE OFF flag is not visible

in the pilot’s altimeter.

The copilot’s altimeter is a pneumatic counter-drum-

pointer type which displays altitude in the same manner

Figure 2-14-2. AIMS Altimeter

as the pilot’s altimeter. It also incorporates a barometric

pressure setting knob and an internal vibrator powered

by the No. 2 DC bus. A minimum of 1 minute of vibrator

operation is require before setting or checking the altime-

powered by No. 2 DC bus is contained in the altimeter

ter.

and requires a minimum of 1 minute warmup before

checking or setting the altimeter. If DC power to the alti-

At ambient pressure, both altimeters should agree within

tude encoder is lost, a warning flag placarded CODE

± 70 feet of the field elevation when the proper barometric

OFF appears in the upper left instrument dial.

pressure setting is set in the altimeter. If the internal

vibrator of either altimeter becomes inoperative due to

The flag indicates that the altitude encoder is inoperative

DC power failure, the pointer drum may momentarily

and that the system is not reporting altitude to ground

hang up when passing from 9 through 0 (climbing) or

stations. The CODE OFF flag monitors only the encoder

from 0 to 9 (descending). This will cause a lag of magni-

function of the altimeter. It does not indicate transponder

tude which will depend on the vertical velocity of the

condition. The AIMS altitude reporting function can be

aircraft and the friction in the altimeter.

inoperative without the CODE OFF flag showing, as in

case of transponder failure or improper control settings.

2-14-9. Radar Altimeter (AN/APN-209A).

It is also possible to get a good Mode C test on the

transponder control with the CODE OFF flag showing.

Radar altimeters are provided for the pilot and copilot and

Display of the CODE OFF flag only indicates an encoder

filght engineer (fig. 2-14-3). The altimeters provide a con-

power failure or a CODE OFF flag failure. In this event,

tinuous indication of the height of the helicopter above

check that DC power is available and the circuit breakers

the surface from 0 to 1,500 feet. Altimeter indications are

are in. If the flag is still visible, radio contact should be

reliable with pitch and roll attitude up to 45_.

made with a ground radar site to determine whether the

Altitude is displayed by a dial, pointer, and a digital dis-

AIMS altitude reporting function is operative. The re-

play. Each altimeter has HI and LO caution lights. The

mainder of the flight should be conducted accordingly.

caution lights on each altimeter can be set independently

of the other altimeter. The caution lights are set by rotat-

2-14-7. Preflight Operation - Altimeter.

ing the LO SET and HI SET knobs until the L index and

If the AIMS altimeter encoding function is to be used

H index on the perimeter of the altimeter are at the de-

during flight, perform the following steps before takeoff:

sired altitudes.

2-14-2

Change 3

TM 1-1520-240-10

When the helicopter descends below the low index set-

will go out, and the pointer will remain at the last valid

ting or rises above the high index setting, the correspond-

indication when power was lost. The altimeters have a

ing HI or LO caution light will illuminate. If helicopter

self-test feature. Pressing the PUSH-TO-TEST knob will

altitude exceeds 1,500 feet, pitch or roll angle exceeds

cause the pointer and digital display to indicate between

45_, or the system is unreliable, the following will occur.

900 and1,100 feet. If LO set and HI set are indexed

The OFF flag will appear, the pointer will move through

below 900 feet, the LO caution light goes out, and the HI

1,500 feet behind the dial mask, and the digital display

caution light comes on. Power to operate the radar altim-

and LO and HI caution lights will extinguish.

eter is supplied by the No. 2 DC bus through the NAV

RAD ALT circuit breaker on the No. 2 PDP.

If power to the system is lost, the following will occur. The

OFF flag will appear, the digital display and caution lights

Figure 2-14-3. Radar Altimeter (AN/APN-209)

2-14-10. Controls and Functions, Radar Altimeter

CONTROLS/

(AN/ APN-209A).

INDICATOR

FUNCTION

LO set index

Indicates altitude trip point

CONTROLS/

for LO caution light.

INDICATOR

FUNCTION

HI set index

Indicates altitude trip point

LO SET knob

Either pilot’s LO SET knob

for HI caution light.

applies power to altimeter

Indicator pointer

Indicates absolute altitude

system. LO set index on

from 0 to 1,500 feet.

both altimeters can be set

independently. Both LO set

Digital indicator

Provides direct reading four

indices must be masked to

digit indication of absolute

turn the set off.

altitude from 0 to 1,500.

HI SET knob

Sets position of HI set index

LO caution light

Comes on when helicopter

and tests altimeter system

descends below altitude on

when pressed.

LO set index.

2-14-3

TM 1-1520-240-10

2-14-21. CHRONOMETER.

is set, pressing the SELECT button will select the next

digit to be set. After the last digit has been selected and

Two digital clocks labeled CHRONOMETER are located

set with the CONTROL button, press the SELECT button

on the copilot and pilot instrument panels (fig. 2-14-4).

to exit the set mode. The annunciator will resume its

Each clock has a six-digit GMT (greenwich mean time)

normal flashing condition to indicate that the GMT clock

display and four-digit selectable display. A test mode is

is running.

provided to check system. A flashing annunciator identi-

fies which clock mode has been selected. There are

2-14-24. Setting LT.

three controls on each clock, a SELECT button, a CON-

TROL button, and a DIM switch.

Press the SELECT button until LT is selected. Simulta-

neously press both the SELECT and CONTROL buttons

to enter the set mode. The tens of hours digit will start

flashing and CONTROL button has full control of the

flashing digit. Use the same sequence as for setting GMT

with the exception that the minutes are already synchro-

nized with the GMT clock and can not be set when in LT

mode.

2-14-25. Setting ET.

The elapsed time allows for count up or count down

modes.

a. Count Up. Press the SELECT button until ET is

selected. Press the CONTROL button to start count up

sequence. The clock will count up to 59 minutes, 59

seconds and then changes to hours and minutes. It will

count up to 99 hours and 59 minutes. Pressing the CON-

Figure 2-14-4. Chronometer

TROL button again resets the ET to zero.

a. SELECT Button. It allows the selection of any of

b. Count Down. Press the SELECT button until ET

three modes on the four-digit display: GMT, LT (local

is selected. Simultaneously press both SELECT and

time), or ET (elapsed time). The six-digit display shows

CONTROL buttons to enter the set mode. A count down

GMT only.

from any time, not to exceed 59 minutes and 59 seconds,

can be set using the same sequence as for setting GMT.

b. CONTROL Button. It is used to set the time se-

Once the last digit is set, pressing the SELECT button

lected on the four-digit display. When the CONTROL and

exits the set mode and the clock is ready to start count

SELECT buttons are pressed simultaneously, the four-

down. Pressing the CONTROL button will start count

digit display is changed from the normal to the time set

down sequence. When the clock reaches zero, an alarm

mode, and the CONTROL button is functional.

becomes active by flashing the numbers and the ET

c. DIM Control Switch. It is used to set the light

counter will begin to count up. To reset the alarm press

intensity of the display. At low light settings, the clock

either the SELECT or CONTROL button.

display is NVG compatible.

2-14-26. Test Mode.

Integral alkaline batteries maintain clock operation when

no aircraft power is applied, but the CONTROL and SE-

To activate the test mode, press and hold the SELECT

LECT buttons are disabled. Power to operate the chro-

button for three seconds and all numerical displays will

nometers is supplied by the DC essential bus through the

show an 8 and all annunciators will be active.

CPLT CLOCK and PLT CLOCK on the No. 1 PDP and

No. 2 PDP.

2-14-27. Master Caution System.

2-14-22. Normal Operation - CHRONOMETER.

The master caution system provides the pilots with a

visual indication of helicopter conditions or faults (fig.

2-14-5 and 2-14-6). The components of the systems are

2-14-23. Setting GMT.

the 712 Master Caution Panel with NVG filter, 714A

Press the SELECT button until GMT is selected. Simulta-

Master Caution/Advisory Panel, two MASTER CAU-

neously press both the SELECT and CONTROL buttons

TION lights with NVG filters, and a CAUTION LT panel

to enter the set mode. The tens of hours digit will start

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

flashing and the CONTROL button has full control of the

control the master caution system is supplied by the DC

flashing digit. Each time the CONTROL button is pressed

essential bus through the LIGHTING CAUTION PN cir-

, the flashing digit will increment. Once the tenth of hours

cuit breaker on the No. 1 PDP.

2-14-7

TM 1-1520-240-10

2-14-28.

712 Master Caution Panel.

714A Master

ments displayed on the capsules and their actual mean-

Caution/Advisory Panel.

ing and cause.

712 An NVG filter is provided for use during NVG opera-

The Master Caution Panel is on the center instrument

tions. The filter fits over the master caution panel and is

panel (fig. 2-14-5 and 2-14-6). Each capsule is labeled

secured in place by hook and pile tape at its base. When

with word segments which are related to the fault or

the filter is in this position, any light coming from the

condition. When a caution capsule illuminates, the word

caution lights will be NVG compatible. For normal opera-

segments lettered into the panel are of an amber color.

tions, the filter is rotated from its base to a horizontal

When they extinguish, the lettering is not readable.

position, and stowed in a compartment above the master

Tables 2-14-1 and 2-14-2 contain lists of the word seg-

caution panel.

EXT PWR

EXT PWR

EAPS 1

EAPS 2

FAIL

FAIL

DUAL HOOK

FAULT

PWR STEER

Figure 2-14-5. Master Caution System 712

2-14-8

TM 1-1520-240-10

Table 2-14-1. Master Caution Panel Capsules 712 (Continued)

WORD SEGMENT

EXPLANATION

NO. 2 ENG N1 CONT No. 2 engine N1 component has failed or the engine condition lever or N1 actuator is not

in the STOP, GND, or FLT position.

NO. 1 ENG XMSN

No. 1 engine transmission oil temperature is above about 190_C.

HOT

NO. 2 XMSN HOT

No. 2 engine transmission oil temperature is above about 190_C.

CM INOP

Countermeasure set has failed.

CM JAM

Countermeasures set has detected interference from other countermeasures sets or sys-

tem is being jammed.

EAPS 1 FAIL

Pressure switch within No. 1 EAPS has sensed a pressure differential of 10 psi, indicat-

ing a partial blockage of inlet air.

EAPS 2 FAIL

Pressure switch within No. 2 EAPS has sensed a pressure differential of 10 psi, indicat-

ing a partial blockage of inlet air.

2-14-29. MASTER CAUTION Lights.

pilots should extinguish the MASTER CAUTION light by

pressing (PUSH TO RESET) the face of the light. The

Two MASTER CAUTION lights on the instrument panels

MASTER CAUTION light is then ready to indicate a sub-

indicate that one or more of the caution capsules have

sequent malfunction of a different system.

illuminated. On the pilot instrument panel, the caution

light is above the airspeed indicator. On the copilot instru-

Once the malfunction is corrected, the affected caution

ment panel, it is above the altimeter.

capsule will extinguish. The HEATER HOT capsule is an

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

Movable NVG filters are attached to the instrument pan-

cycled OFF then ON while another caution capsule is lit,

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

the MASTER CAUTION light may remain illuminated af-

can be rotated over the two MASTER CAUTION lights

ter the generator comes back on and the associated

making the lights NVG compatible. After the MASTER

GEN OFF capsule extinguishes. If this occurs, press to

CAUTION has illuminated and the condition noted, the

extinguish the MASTER CAUTION light.

Figure 2-14-6. Master Caution /Advisory Panel 714A

2-14-10

TM 1-1520-240-10

Figure 2-15-1. No Step, No Handhold, and Walkway Areas

2-15-4

TM 1-1520-240-10

Figure 2-15-2. Servicing Diagram (Sheet 1 of 4)

2-15-5

TM 1-1520-240-10

Figure 2-15-2. Servicing Diagram (Sheet 2 of 4)

2-15-6

TM 1-1520-240-10

Figure 2-15-2. Servicing Diagram (Sheet 3 of 4)

2-15-7

TM 1-1520-240-10

Figure 2-15-2. Servicing Diagram (Sheet 4 of 4)

2-15-8

TM 1-1520-240-10

Figure 2-15-4. Protective Covers

2-15-19

TM 1-1520-240-10

Figure 2-15-5. EAPS Protective Covers

2-15-20

TM 1-1520-240-10

Figure 2-15-6. Installation of Helicopter Security Devises (Typical)

2-15-21/(2-15-22 blank)

TM 1-1520-240-10

Figure 3-2-1. Interphone Stations

3-2-2

TM 1-1520-240-10

3-2-3. Antenna System.

CONTROLS/

FUNCTION

INDICATOR

Antennas used for avionics communications and elec-

Off

Released position disables mi-

tronic systems equipment are shown in figure 3-2-3. This

crophone.

figure shows the maximum antenna configuration. All

antennas illustrated may not appear on all helicopters.

Talk

Depressed position: enables

3-2-4. UHF-AM Have Quick II Radio (AN/ARC-164).

headset microphone.

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

Hoist Control PTT

Two position PTT Switch.

located on the center console. It is capable of providing

Switch (on hoist

normal and ECCM, Anti-Jam (AJ) two-way voice com-

control grip) Posi-

munications in the band from 225.000 to 399.975 MHz in

tion

25 kHz increments. The HQ II is capable of operating with

Off

Released position; disables mi-

the Basic HAVE QUICK radio. It also provides 20 preset

crophone.

frequencies and will monitor and transmit on a perma-

Talk

Depressed position; enables

nent guard channel (243.000 MHz). When in the AJ

headset microphone

mode preset 20 is restricted to AJ operations. The usual

operating mode for the radio set is the normal mode

HOT MIKE switch

Three position toggle switch

where the radio uses 1 of 7,000 frequencies. Power for

on HOIST OPERA-

selects hoist operator’s inter-

the UHF-AM Have Quick II radio set is supplied by the 28

TORS PANEl

phone operating mode.

volt essential bus through the COMM UHF AM circuit

(Chapter 4)

breaker on the No. 1 PDP.

OFF

Requires operation of PTT

There are presently three configurations of the AN/ARC

switch for interphone commu-

164-UHF/AM radio. The following paragraphs identify

nications.

the visual differences in their configurations.

HOT MIKE

Operation of PTT switch not

required for interphone com-

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

munications.

Have Quick) 100MHz selector for the hundreds digit only

has a 2 and a 3 position.

MOM ON

Operation of PTT switch re-

quired for interphone commu-

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

nications. (Spring loaded to

single WOD entry only). Has a four position selector for

OFF position when released.)

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

Gunner’s Foot

Two position pressure sensi-

label adjacent to the Pre-set channel selector.

Switch Position

tive switch mounted in move-

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

able floor mat.

above, but includes EMB label adjacent to the Pre-set

Off

Released position; disables mi-

channel selector.

crophone.

Reverse compatible communications between HQ II and

On

Depressed position; enables

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

microphone.

entering a single WOD or selecting the appropriate

MWOD and net number with a suffix 00.

3-2-5. 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 radios

must have clocks which are synchronized. In addition, all

participating radios must have the same word-of-day

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

(WOD) and net number data when in the AJ mode.

3-2-3

TM 1-1520-240-10

3-2-6. Word-of-Day.

Four operating modes are used within the radio set to

initiate various Have Quick (HQ) programing functions.

The WOD programs the frequency hopping rate and pat-

They are accessed via preset 20 with the frequencies

tern. Without it, the radio cannot function in the AJ mode.

listed in Table 3-2-1. The functions are Operate/verify,

A WOD is made up of a maximum of six WOD segments

MWOD load, MWOD erase, and Frequency Managed

plus a date code. The Have Quick II radios are capable

Training (FMT) frequency load.

of storing up to six WODs, thus allowing for multi-day use

of the radio set. This technique is known as multiple

word-of-day (MWOD) loading. The basic have QUICK

radio allows loading a single WOD, in volatile memory.

1. Glide slope

9. ADF loop and sense antennas

2. Radar warning

10. UHF -AM

3. HF ARC-220 antenna

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

4. VHF navigation

12. FM homing

5. Radar warning

13. Doppler navigation

6. IFF

7. ECM antennas

14. Radar warning blade antenna

8. Marker beacon

15. Radar altimeter

Figure 3-2-3. Antenna Locations

3-2-4

TM 1-1520-240-10

3-2-9. Conferencing.

CONTROLS/

FUNCTION

In the AJ mode, the radio has the capability to receive

INDICATOR

and process two simultaneous transmissions on the

TONE

Momentary contact switch.

same net. This conferencing capability is selected by the

Pressing the TONE switch

hundredth and thousandth digits of WOD segment 2,

when in the normal mode en-

loaded using channel position 19 and is disabled when

ables a 1020 Hz tone on the

operating in the secure speech mode.

selected frequency, unless

In a conference net, the second transmitting radio will

TOD has been accepted in

automatically shift its transmission frequency by 25 kHz

which case a1667 Hz-tone is

when it monitors a transmission on the primary net fre-

heard prior to the 1020 Hz

quency. The wide band receiver will monitor both trans-

tone. When A-3-2-T switch is

missions without the interference normally associated

in A, it enables TOD transmis-

with two radio transmitting on the same frequency simul-

sion followed by a 1020 Hz

taneously. Three simultaneous transmissions will create

tone on the selected frequen-

garbled reception.

cy. When A-3-2-T switch is in

3-2-10. Controls and Function, UHF-AM Have Quick

T, it initiates the emergency

II Radio (AN/ARC-164). (fig. 3-2-4)

startup of the TOD clock.

When in the load mode. Press-

CONTROL/

FUNCTION

ing the TONE switch with

INDICATOR

channels 1, 14, or 15 through

Function Select

Four position rotary switch

20 selected in the manual

Switch

used to select radio operating

mode enters the MWOD data

into non-volatile memory.

mode.

Pressing the TONE switch

OFF

Power to set is disabled; radio

when in the erase mode,

set inoperative.

erases all MWOD data from

MAIN

Radio set can be used to

non-volatile memory.

transmit and receive; guard re-

VOL

Rotary control used to adjust

ceiver inoperative.

radio output volume.

BOTH

Radio set can be used to

SQUELCH Switch

Two position toggle switch to

transmit and receive; guard re-

select radio squelch mode.

ceiver operates.

OFF

Squelch is disabled

ADF

Not used.

ON

Squelch is enabled

Frequency Mode

Three position rotary control

Selector

used to select frequency tun-

ing mode.

MANUAL

Permits manual frequency

selection using frequency con-

trols.

PRESET

Permits selection of preset

channel frequencies in radio

set (maximum of 20 channels).

GUARD

Automatically disables the anti-

jam mode and tunes radio set

to guard channel frequency

(243.000 MHz).

Frequency Selec-

Five rotary controls used to se-

tors

lect radio operating frequency

or state.

Figure 3-2-4. UHF-AM Have Quick II Radio

(An/ARC-164)

3-2-6

TM 1-1520-240-10

Figure 3-2-5. VHF AM/FM Radio Set (AN/ARC-186)

b. Transmit-receiver mode.

(7)

Using a soft lead pencil, record the loaded

frequency opposite the channel number on the snap-on

(1)

Mode select switch - TR.

cover.

(2)

Frequency Control/Emergency Select

(8)

Using the above procedure, preset any oth-

Switch - As required. If greater receiver sensitivity is

er channels and install the snap-on cover.

required, set the SQ DIS/TONE switch to SQ DIS.

3-2-16. VHF/FM Radio Set (AN/ARC-201).

(3)

VOL control - As required.

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

c. Stopping. Mode select switch - OFF.

and provides two-way frequency modulated (FM narrow

d. Presetting channels. Perform the following steps

band voice communications.

to preset a channel to a desired frequency.

a. The following items from the airborne radio sys-

(1)

Mode select switch - TR.

tem.

(2)

Frequency select switch - MAN.

ITEM DESCRIPTION

(3)

Rotate the four frequency select switches

1.

Receiver-Transmitter Radio Panel Mounted

until the desired frequency is displayed.

(RT-1476)

(4)

Rotate the preset channel selector until the

2.

Amplifier (AM 7189)

desired channel appears in the preset CHAN indicator.

b. Essential Operational Technical Characteristics.

(5)

Remove the snap-on cover.

Except where specifically indicated otherwise, the follow-

(6)

Momentarily set the bandwidth WB, NB,

ing operational/technical parameters are the minimum

MEM LOAD switch to MEM LOAD. The preset frequency

essential characteristics. Unless otherwise specified,

is now in memory.

they apply to each radio configuration.

3-2-11

TM 1-1520-240-10

CONTROLS/

FUNCTION

CONTROLS/

FUNCTION

INDICATOR

INDICATOR

POS. 1-6

In single channel mode, preset

SEND/OFST

Modify a single channel oper-

frequencies are selected or

ating frequency, manually se-

lect or preset, to include offsets

loaded. In FH or FM-M mode,

of + 5 or +10 kHz. It has a sec-

frequency hopping nets are se-

ond function on initiating an

lected.

ERF Transmission if a Hopset

CUE

Used by a non-ECCM radio to

or Lockout.

signal to CUE or ECCM radio.

Set is in the holding memory

and the Mode Switch is in the

IFM RF Selector

FH-M position.

OFF

(Bypass) - 10 watts

TIME

Used to display or change the

LO

(Low Power) -2.5 watts

time setting maintained within

each RT.

NORM

(Normal) -10 watts

FILL

Used to fill ECCM parameters

HI

(High power) - 40 watts

from an external fill device.

Entry of ECCM parameters is

Display

The display generally operates

initiated by the H-LD button on

in conjunction with the key-

the keyboard with the FUNC-

board. Other displays may be

TION switch in LD or LD-V.

selected by the FUNCTION

and MODE selectors.

Keyboard

A 15- button array of switches

in a 4 x 4 matrix, used to insert

data or select data for display.

The keyboard is comprised of

10 numerical buttons, three

special functions, and two

command buttons.

Switches 1 - 9

Used to key in frequencies,

load time information, or off-

sets.

CLR

Used to zeroize the display or

to clear erroneous entries.

0 (H-LD)

Used to enter zeroes. Second

Figure 3-2-6. VHF/FM Radio Set (AN/ARC-201)

function (hold) initiates transfer

of ECCM parameters.

3-2-18. Voice Security Equipment TSEC/KY-58.

STO/ENT

Initiate entry of all data by key-

board entry. Its second func-

The voice security equipment is user with the FM band

tion is to store a received Hop-

of the No. 1 VHF AM/FM radio to provide secure two-way

set or Lockout Set held in hold-

communication. The equipment is controlled by the re-

ing.

mote control unit (RCU) Z-AHP mounted on the right side

of the console. The POWER switch must be at ON, re-

FREQ

Display the current operating

gardless of the mode of operation, whenever the equip-

frequency during single chan-

ment is installed. Power to operate the voice security

nel (manual or preset) opera-

system is supplied by the No. 2 DC bus through the

tion.

COMM KY-28 circuit breaker on the No. 2 PDP.

3-2-13

TM 1-1520-240-10

3-2-19. Controls and Functions. (fig. 3-2-7)

CONTROLS/

FUNCTION

INDICATOR

ZEROIZE Switch

Momentary contact toggle

(under spring-

switch used to clear (ZER-

loaded cover)

OIZE) any crypto-net variables

stored in the TSEC/KY-58.

Delay Switch

Two position toggle switch;

DELAY position used when re-

ceived signal is to be retrans-

mitted.

PLAIN/C/RAD1

Two position rotary switch

Figure 3-2-7. Remote Control Unit TSEC/KY-58

Switch

used to select TSEC/KY-58 op-

(Z-AHP)

erating mode. A third position

(C/RAD 2) is covered and

locked out.

(3)

Pull out and lift up the POWER switch to ON.

A beeping tone and background noise will be heard in the

PLAIN

Permits normal (unsecured)

headset. Before the set can be used, the tone must be

communications on associated

cleared by momentarily keying the No. 1 VHF AM/FM

FM radio set.

radio with the PTT switch.

C/RAD1

Permits secured communica-

(4)

Set the PLAIN C/RAD1 switch to C/RAD1.

tions on associated FM radio

set.

(5)

If the signal is to be retransmitted, pull out

and lift up the DELAY switch to (ON).

FILL Switch

Six position, rotary switch,

used to select any of six stor-

(6)

Clear voice procedures: To operate in

age registers for storage of

clear voice (plain text) simply:

crypto-net variable (CNV).

(a) Set the PLAIN-C/RAD switch to

MODE Switch

Three position rotary switch

PLAIN.

used to select the operating/

(b) Operate the equipment.

loading mode of the TSEC/

KY-58.

b. Zeroizing procedures.

OP

Allows normal operation of

KY-58.

NOTE

LD

Allows normal loading of CNV.

Instructions should originate from the net con-

troller or commander as to when to zeroize

RV

Allows remote loading of CNV.

the equipment.

POWER ON Switch

Two position toggle switch

(1)

Lift the red ZEROIZE switch cover.

Position

used to apply power to TSEC/

KY-58.

(2)

Push the spring-loaded ZEROIZE switch

up. This will zeroize position 1-16.

(3)

Close the red cover. The equipment is now

zeroized and secure voice communications are no lon-

3-2-20. Normal Operation.

ger possible.

c. Automatic remoter keying procedures.

a. Operating procedures for secure voice.

NOTE

NOTE

Automatic remote keying (AK) causes an old

To talk in secure voice, the KY-58 must be

CNV to be replaced by a new CNV. Net con-

loaded with any number of desired variables.

troller simply transmits the new CNV over the

air to your KY-58.

(1)

Set the MODE switch to OP.

(1)

The net controller will use a secure voice

channel, with directions to stand by for an AK transmis-

(2)

Set the FILL switch to the storage register

sion. Calls should not be made during this stand-by ac-

which contains the required CNV.

tion.

3-2-14

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