F16C/D (BLOCKS 50 AND 52+). FLIGHT MANUAL (15 OCTOBER 2002) - page 14

T.O. GR1F16CJ1

196

DC Power Distribution Diagram

EMERGENCY AC BUS NO. 1

EMERGENCY DC BUS NO. 1

GR1F-16CJ-1-2155-1X37

ALT REL Button

AVTR Switch

 (branches A & B)

FUEL LOW Caution Lights

FLCS Power Source

CADC Caution Light

Cockpit Temp Control

C

DBU ON Warning Light

IFF

AC TO DC CONVERTER

OBOGS Monitor

Antiskid/Chan 1

 Brakes

CANOPY Warning

 Light

MLG WOW

 (branches A & B)

NLG WOW

 (branches A & B)

RPM Indicator

BATTERY BUS NO. 1

Drag Chute

UHF Radio

Utility Light

VMS

NONESSENTIAL DC BUS

NACELLE NONESS DC BUS NO. 1

EPU ON

(EXCEPT

DURING GND

TEST) OR

STBY ON

BATTERY

 (branches A & B)

EGI

 (branches A & B)

FLCS Reset Switches

 (branches A & B)

FLCS Warning Light

 Light (branches A & B)

FLCS FAULT Caution

DF

C

LG DOWN Permission Button

LG WHEELS Down Lights

MAL & IND LTS Test/BRT/

MASTER ARM Switch

 DIM Feature

NWS/AR System

Probe Heat Monitor

PROBE HEAT Switch

Speedbrakes

Stick Trim

WPN REL Button

DR

VHF Radio

TACAN

OCSC Trip

NACELLE NONESSENTIAL DC BUS NO. 2

MFD Heater

ENGINE Warning Light

EPU

HYD/OIL PRESS

 Warning Light

Intercom

JFS

LG Downlock Relays

 (WHEELS down lights)

LG Uplock/Downlock

Master Caution

FTIT Indicator

TWS

PX III

AOA Indexer

MMC (Side A)

ASIU

AVTR Heater

ECM Control

ECM Fwd Transmitter

ECM Processor

FCR

Fuel Pumps 1, 2 & 4

ECM Aft Transmitter

MAX POWER Switch

Nacelle Ejector Shutoff

TGP (right inlet power and control)

TISL

D

EMER JETT Button

MSL Step Switch

Figure 132.(Sheet 3)

T.O. GR1F16CJ1

Change 1197

EMERGENCY AC BUS NO. 2

EMERGENCY DC BUS NO. 2

GR1F-16CJ-1-2155-2X37

FLCS Power Source

 (branches C & D)

FLCS Reset Switch

FLCS Warning Light

 (branches C & D)

 (branches C & D)

AC TO DC CONVERTER

EPU FUEL Quantity

 Indicator

ENGINE FIRE Warning

 Light

BATTERY BUS NO. 2

CSFDR

EDU

ELEC SYS Caution Light

OVERHEAT Caution

 Light

ESSENTIAL DC BUS

EPU ON

(EXCEPT

DURING

GND TEST)

LEGEND:

Can be powered by EPU

Powered thru NONESS AC Bus No. 2

EPU

Parking Brake

SAI

HUD

Gun

* Power available from the battery bus box with MAIN PWR switch OFF.

ANTI ICE Switch

AR System Lights

Auto Fwd Fuel Trans

Autopilot

AVTR

 Light

CABIN PRESS Caution

CAMERA/GUN Trigger

Chaff/Flare Dispensers

*Canopy Actuator

DBU ON Warning Light

 (branches C & D)

EMER JETT Button

Engine Bleed Air Valves

ENGINE FAULT Caution Light

FLCS FAULT Caution

EQUIP HOT Caution Light

 Light (branches C & D)

DR

Altimeter (PNEU)

Antiskid/Chan 2 Brakes

OCSC Trip

Aft Seat Hud Monitor

Data Transfer Unit

NLG WOW (branches

 C & D)

Powered thru Fwd OCSC

ELECTRICAL

MECHANICAL

 (close capability)

ILS

LANDING/TAXI/EXT

 Light Switches

INLET ICING Caution

 Light

ICP/IKP

WPN REL Button

DF

C

LG Door Close

LG Hyd Isolation

LG UP-DN Command

NUCLEAR CONSENT Switch

MASTER ARM Switch

OXY LOW Warning Light

MFD Video Control

STORES CONFIG Caution

SEAT NOT ARMED

 Light

 Caution Light

LEF Asymmetry Brake

FUEL MASTER Switch

GCU's (main/standby)

Hook

LG Warning Light (handle)

MLG WOW (branches

 C & D)

ZEROIZE Switch

Fuel Pumps 3 & 5

NVP (left inlet

 ARM/Release

Stations 1, 2, 3, 3A, 4,

 5, 6, 7, 7A, 8 & 9

Tank Inerting

Cockpit Pressure Dump

MMC (side B)

OBOGS Caution Light

Upfront Controls

Data Link

power and control)

Radar Altimeter

D

Antiskid/Chan 2 Brakes

Figure 132.(Sheet 4)

T.O. GR1F16CJ1

198

HYDRAULIC SYSTEM

Refer to figure 133. Hydraulic pressure is supplied

by 3000 psi hydraulic systems designated as systems

A and B. The systems are powered by two

independent enginedriven pumps located on the

ADG. Each system has a reservoir to store hydraulic

fluid. The reservoirs are pressurized by their

respective hydraulic system to insure positive

pressure at the pump. For hydraulic system cooling,

refer to ENGINE FUEL SUPPLY SYSTEM, this

section.

Both systems operate simultaneously to supply

hydraulic power for the primary flight controls and

LEF's. If one of the systems should fail, the

remaining system provides sufficient hydraulic

pressure; however, the maximum actuation rate of

the FLCS is reduced. System A also supplies power

to the FFP and the speedbrakes. All remaining

utility functions, consisting of the gun and gun purge

door, AR system, LG, brakes, and NWS, are supplied

by system B. System B also charges the brake/JFS

accumulators (which provide start power for the JFS

and backup pressure for the brakes), provided the

engine is rotating at a minimum of 12 percent rpm.

System B takes between 40 seconds (hot ambient

conditions) and 60 seconds (cold ambient conditions)

to recharge the brake/JFS accumulators.

The LG can be extended pneumatically in the event

of hydraulic system B failure. Should both hydraulic

systems fail, a third hydraulic pump located on the

EPU automatically provides hydraulic pressure to

system A. Refer to EMERGENCY POWER UNIT

(EPU), this section, for a further discussion of the

EPU.

Each hydraulic system has an FLCS accumulator

which is isolated from the main system by check

valves. These FLCS accumulators serve a dual

function. If demand exceeds the pump maximum

flow rate during rapid control surface movement, the

FLCS accumulators provide additional hydraulic

pressure. Also, if both hydraulic systems fail, the

FLCS accumulators provide adequate hydraulic

pressure to the flight controls while the EPU comes

up to speed. Refer to SERVICING DIAGRAM, this

section, for servicing/specifications information.

HYD PRESS INDICATORS AND WARNING LIGHT

Refer to figure 134.

HYD PRESS Indicators

The HYD PRESS indicators, one for system A and

one for system B, are located on the right auxiliary

console. The indicators are powered by emergency ac

bus No. 2.

HYD/OIL PRESS Warning Light

A HYD/OIL PRESS warning light, located on the

right glareshield, comes on when hydraulic system

A or B pressure drops below 1000 psi or when engine

oil pressure drops below 10 (

"

2) psi. For the oil

pressure function only, there is a 30second time

delay in the light circuit to minimize transient lights

during negative g maneuvers. The light is powered

by battery bus No. 1.

EMERGENCY POWER UNIT (EPU)

Refer to figure 135. The EPU is a selfcontained

system which simultaneously provides emergency

hydraulic pressure to system A and emergency

electrical power. The EPU automatically activates

when both main and standby generators fail or when

both hydraulic system pressures fall below 1000 psi.

The EPU may be operated manually regardless of

failure conditions.

The EPU requires dc power from either battery bus

No. 1 or No. 2 for automatic or manual activation.

When the EPU is operating, the emergency ac and dc

buses are powered by the EPU generator. To reduce

electrical loads, the nonessential and essential dc

buses are unpowered whenever the EPU is operating

(except when activated for ground test using the

EPU/GEN test switch).

When operating, the EPU augments hydraulic

system A as required. If the normal system A

hydraulic pump fails, the EPU is the only source of

system A pressure.

The EPU uses engine bleed air and/or hydrazine to

operate. Normally, engine bleed air is used to

maintain operating speed. When bleed air is

insufficient, hydrazine augmentation automatically

occurs. Hydrazine is always used when the EPU is

commanded to start except when activated during

ground test using the EPU/GEN test switch.

T.O. GR1F16CJ1

199

On system command, hydrazine is forced by nitrogen

pressure into a decomposition chamber. The gaseous

products of the reaction spin the turbine/gearbox

which then powers the EPU generator and hydraulic

pump. Hydrazine exhaust is vented overboard on the

lower inboard side of the right strake and consists

primarily of nitrogen, hydrogen, ammonia, and

water. The temperature of exhaust gases can reach

1600

_

F and will ignite in the presence of a flame. The

exhaust gases have an ammonia odor, are irritating

to the nose and eyes, and should be avoided to the

maximum extent possible.

EPU CONTROLS AND INDICATORS

Refer to figure 136.

EPU Ground Safety Switch

The ground safety switch, located on the right side of

the engine inlet, is used to disable the EPU on the

ground. With the EPU safety pin installed, the EPU

does not operate.

EPU Switch

The EPU switch, located on the EPU control panel, is

a threeposition toggle switch.

Functions are:

D

OFF

S

Prevents or terminates EPU operation on the

ground (WOW).

S

Does not prevent or terminate EPU operation in

flight for main and standby generator failures if

switch was cycled or placed to NORM at anytime

since takeoff (since WOW).

S

Prevents EPU operation in flight if switch has

remained in the OFF position since takeoff (since

WOW).

S

Terminates EPU operation in flight except during

main and standby generator failures.

D

NORM - The system is armed for automatic

operation except during engine shutdown on the

ground. With WOW and throttle in OFF, the EPU

does not activate when the main and standby

generators drop off line.

D

ON - Commands EPU to run regardless of failure

conditions. Operation will cease when switch is

positioned to OFF except for main and standby

generator failures in flight.

The switch has a split guard; the top half can be raised

to move the switch to ON, and the bottom half can be

raised to move the switch to OFF. When both sections

of the guard are down, the switch is retained in the

NORM position.

EPU Run Light

The EPU run light, located on the EPU control panel,

illuminates when the EPU turbine speed is within the

proper range and the EPUdriven hydraulic pump

discharge pressure is above 2000 psi.

HYDRAZN Light

The HYDRAZN light, located on the EPU control

panel, illuminates when the EPU is commanding

hydrazine for operation (whether hydrazine is

available or not) or if a primary speed control failure

has occurred.

AIR Light

The AIR light, located on the EPU control panel,

illuminates whenever the EPU has been commanded

to run with the EPU safety pin removed. It remains

on even when the EPU is augmented by hydrazine.

EPU/GEN Test Switch

The EPU/GEN test switch, located on the TEST

switch panel, has positions of OFF and EPU/GEN.

The switch is springloaded to the OFF position. It

provides a means to test the EPU generator and EPU

PMG output to FLCS on the ground without using

hydrazine.

EPU FUEL Quantity Indicator 

C

 

DF

Refer to figure 13. The EPU FUEL quantity

indicator, located on the right auxiliary console, is

graduated 0100 and indicates the percent of

hydrazine remaining. The indicator is powered by

battery bus No. 2.

Hydrazine Leak Detector

The hydrazine leak detector is a silicone base,

mustard yellow disc visible through access door 3208.

The viewing area is black on one half to provide

contrast with the mustard yellow disc. The mustard

yellow turns purple/black in the presence of

hydrazine and/or its vapors, indicating a leak in the

EPU and/or fuel tank system.

T.O. GR1F16CJ1

1100

GR1F-16CJ-1-0037-1X37

Hydraulic Power Supply

(Typical)

FILTER

ENGINE

DRIVEN

HYDRAULIC

PUMP

EPU

HYDRAULIC

PUMP

FILTER

FLCS

ACCUMULATOR

THERMAL

BYPASS

FUEL/OIL

HEAT EX-

BRAKE/JFS

ACCUMULATORS

HYD PRESS

INDICATOR

WARNING LIGHT

LEF'S

RUDDER

FLAPERONS

SPEEDBRAKES

FFP

LG SYSTEM

NWS

HYDRAULIC

RESERVOIR

GUN SYSTEM

AR SYSTEM

BRAKE SYSTEM

JFS SYSTEM

RESERVOIR

PRESSURIZATION

ACCUMULATOR

RESERVOIR

PRESSURIZATION

ACCUMULATOR

DUMP AND

RELIEF VALVE

DUMP

AND

RELIEF

MANIFOLD

HORIZONTAL

TAILS

CHANGER

B

P

SYSTEM A

S

T

PRESS

HYD/OIL

DRAG CHUTE

SYSTEM

Figure 133.(Sheet 1)

T.O. GR1F16CJ1

1101

GR1F-16CJ-1-0037-2X37

FLCS

ACCUMULATOR

FILTER

ENGINE

DRIVEN

HYDRAULIC

PUMP

FILTER

LG DOORS

UPLOCK

ACTUATED

FILTER

WARNING LIGHT

HYD PRESS

INDICATOR

HYDRAULIC

RESERVOIR

DUMP AND

RELIEF VALVE

B

P

SYSTEM B

S

T

PRESS

HYD/OIL

DRAG CHUTE

ACCUMULATOR

S

B

P

T

LEGEND:

ISOLATION VALVE

BLEED VALVE

FILL CONNECTOR

QUICK DISCONNECT

CHECK VALVE

PRESSURE SWITCH

PRESSURE TRANSMITTER

BYPASS

ELECTRICAL

PRESSURE

RETURN

SUPPLY

Figure 133.(Sheet 2)

T.O. GR1F16CJ1

1102

HYD/OIL PRESS Warning Light (Red)

System A HYD PRESS Indicator

System B HYD PRESS Indicator

HYD PRESS Indicators and Warning Light

(Typical)

GR1F16CJ10036X37

2

3

1.

2.

3.

2

3

1

1

C DF

DR

Figure 134.

EPU Fired Indicator

The EPU fired indicator is located next to the EPU

ground safety switch on the right side of the engine

inlet. Normally, the indicator displays a gray and

black disc. If the EPU has been activated, the

indicator displays six equally spaced black and white

triangles.

EPU OPERATION

The EPU is designed to operate automatically for

main and standby generator failure, dual hydraulic

system failure, PTO shaft or ADG failure, and engine

flameout or if the engine is shut down in flight. The

EPU can also be activated manually. After receiving

any start command, the EPU requires approximately

2 seconds to come up to speed.

EPU startup may not be audible. Once operating,

however, the EPU may be heard but does not sound

the same as during the EPU ground check. A lack of

sound during EPU startup does not indicate lack of

EPU operation which must be confirmed by

monitoring the EPU run light. EPU rpm is controlled

by three speed controls. The primary and secondary

speed controls are based on EPU rpm. The tertiary

speed control is based on EPU PMG frequency.

When the EPU is operating, engine thrust settings

should be maintained to prevent using hydrazine.

This normally requires a minimum of 

PW 229

 7580,

129

GE

 8290 percent rpm depending on pressure

altitude.

If the engine fails, hydrazine alone is used to power

the EPU. With hydrazine only, operating time of the

system is approximately 10 minutes under normal

load requirements. Increased flight control move

ment reduces this operating time. When the EPU is

the sole source of hydraulic power, EPU loss results

in loss of aircraft control.

T.O. GR1F16CJ1

1103

GR1F-16CJ-1-0038A37

OPEN IF EPU

SAFETY PIN

INSTALLED

LEGEND:

BLEED AIR
HYDRAZINE FUEL
HYDRAULIC FLUID SUPPLY

EPU START UP AND CONTROL POWER

EPU TEST RUN COMMAND

CLOSED ON

START, MAIN

GEN ON LINE

AUTO ARM/

DISABLE

OPEN WITH

WOW &

THROTTLE

BELOW IDLE

RUN LIGHT OFF

FOR OVER OR

UNDERSPEED

CONDITION

EPU/GEN TEST

SWITCH

EPU COMMAND INDICATION

HIGH PRESSURE

BLEED AIR

BLEED AIR

VALVE

RUN

COMMAND

(AUGMENT)

TEST RUN

COMMAND

(BLEED AIR

ONLY)

OVERSPEED SHUTOFF COMMAND

(TERTIARY CONTROL)

TO EMERGENCY

AC BUSES

TO CONVERTER/

REGULATORS

CLOSED FOR

PRESSURE > 2000 PSI

TO HYD

SYS A

EPU RUN LIGHT

CLOSED IF

MAIN GEN

OFF LINE

CLOSED IF

STANDBY GEN

OFF LINE

SPEED

MONITOR

HYDRAULIC

PUMP

CONTROL VALVES

5 KVA

GENERATOR

AC POWER

GENERATOR

CONTROL UNIT

HYDRAZINE FUEL

HYD SYS A

CLOSED FOR

PRESSURE < 1000 PSI

28 VDC PWR

MAIN

GENERATOR

STANDBY

GENERATOR

AUGMENT

MODE

BLEED AIR

MODE ONLY

Shown in augment mode with main

Emergency Power Unit Schematic (Typical)

EPU GROUND

SAFETY SWITCH

SOLENOID

ELECTRICAL

MECHANICAL

FROM HYD SYS A RSVR

EPU

EPU

CONTROLLER

VALVE

ASSY

NITROGEN

EPU FUEL

QUANTITY

PRESSURE

INDICATOR

GASEOUS NITROGEN

FILL

CONNECTOR
QUICK

DISCONNECT

HYDRAULIC PRESSURE

HYD SYS B

EPU PMG FAIL INDICATION FROM CONVERTER/REGULATORS

EPU GENERATOR FAIL INDICATION

STANDBY GENERATOR

FAIL INDICATION

MAIN GENERATOR

FAIL INDICATION

ELEC

SYS

P

M

G

NOTE:

and standby generators failed.

PX III

PX II

7 KVA

Figure 135.