NATOPS FLIGHT MANUAL NAVY MODEL AV--8B/TAV--8B 161573 AND UP AIRCRAFT (2008)

A1-AV8BC-410-100

008 00

Change

Page

Nomenclature

Index No.

Ref Des

AC CIRCUIT BREAKER PANEL ASSEMBLY

52A-C105

FWD FUS FAN A (ZONE A3)

22CBC025

FWD FUS FAN B (ZONE B3)

22CBC026

FWD FUS FAN C (ZONE C3)

22CBC027

AFT CKPT FAN A (ZONE A4)

22CBC061

AFT CKPT FAN B (ZONE B4)

22CBC062

AFT CKPT FAN C (ZONE C4)

22CBC063

FWD CKPT FAN A (ZONE A5)

22CBC035

FWD CKPT FAN B (ZONE B5)

22CBC036

FWD CKPT FAN C (ZONE C5)

22CBC037

AC ESSENTIAL PANEL ASSEMBLY

52A-N131

FWD FUS COOL FAN (ZONE C6)

22CBN025

FWD FUS COOL FAN (ZONE D6)

22CBN026

FWD FUS COOL FAN (ZONE E6)

22CBN027

CKPT COOL FAN (ZONE C7)

22CBN035

CKPT COOL FAN (ZONE D7)

22CBN036

CKPT COOL FAN (ZONE E7)

22CBN037

AFT CKPT FAN (ZONE C11)

22CBN061

AFT CKPT FAN (ZONE D11)

22CBN062

AFT CKPT FAN (ZONE E11)

22CBN063

ANNUNCIATOR LIGHT CONTROLLER

27A-D007

ARMT STORES MANAGEMENT CONTROL -

—

INDICATOR C-10940/AYQ-13 COOLING AIR

FITTING

CAUTION/ADVISORY INDICATOR LIGHT

27A-F011

ASSEMBLY

COCKPIT AVIONICS COOLING FAN

22B-F038

COCKPIT DIFFERENTIAL PRESSURE SWITCH

22S-D070

COORDINATE DATA MONITOR ID-2251/ASQ-179

—

COOLING AIR FITTING

DC CIRCUIT BREAKER PANEL ASSEMBLY

52A-C104

CAB ECS NO. 1 (ZONE D7)

22CBC016

CKPT FAN CONT (ZONE E4)

22CBC074

DC ESSENTIAL/MAIN PANEL ASSEMBLY

52A-P133

CABIN ECS CB NO. 1 (ZONE D4)

22CBP016

CKPT COOL FAN (ZONE E4)

22CBP074

DIGITAL DISPLAY INDICATOR IP-1318/A

—

COOLING AIR FITTING

Figure 1. Forward Avionics Cooling System Component Locator (Sheet 10)

A1-AV8BC-410-100

008 00

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Page

Nomenclature

Index No.

Ref Des

ECS CONTROL PANEL ASSEMBLY

22A-F048

PRESS SWITCH

22S-F033

FORWARD RELAY NO. 1 PANEL ASSEMBLY

52A-C015

GND PWR FAN CONTROL RELAY

22K-C077

COCKPIT COOLING FAN RELAY

22K-C075

REAR COCKPIT COOLING FAN RELAY

22K-C076

ASMCI GND PWR RELAY

1K-C097

FORWARD RELAY NO. 2 PANEL ASSEMBLY

52A-C113

20K FT ALT RELAY

70K-C028

FWD FUS COOLING FAN CONTROL RELAY

22K-C028

COCKPIT COOL CANCEL RELAY

22K-C066

WEIGHT ON WHEELS RELAY NO. 1

12K-C053

REAR COCKPIT FAN FAIL RELAY

22K-C064

COCKPIT FAN FAIL RELAY

22K-C065

REAR COCKPIT COOL CANCEL RELAY

22K-C067

FWD FUS FAN FAIL RELAY

22K-C071

GROUND COOLING CONTROL VALVE

22L-D040

GROUND COOLING FAN

22B-D029

GROUND COOLING VALVE

22MAA510

HEAD-UP DISPLAY UNIT SU-128/A COOLING AIR

—

FITTING

INERTIAL NAVIGATION UNIT CN-1561/ASN-130A

—

COOLING PLENUM ASSEMBLY

INERTIAL NAVIGATION UNIT CN-1649/ASN-139

—

COOLING PLENUM ASSEMBLY

INS CHECK VALVE

22VAD528

INS PLENUM CHECK VALVE

22VAD529

RAM-AIR VENT CHECK VALVE

22VAD527

REAR CAUTION/ADVISORY INDICATOR LIGHT

27A-H045

ASSEMBLY

REAR COCKPIT AVIONICS COOLING FAN

22B-H072

REAR COORDINATE DATA MONITOR ID-2251/

—

ASQ-179 COOLING AIR FITTING

REAR DIGITAL DISPLAY INDICATOR IP-1318/A

—

COOLING AIR FITTING

Figure 1. Forward Avionics Cooling System Component Locator (Sheet

11)

A1-AV8BC-410-100

009 00

1 February 1990

Page 1

ORGANIZATIONAL MAINTENANCE

PRINCIPLES OF OPERATION

ANTI-G SYSTEM

Reference Material

Environmental Control System

A1-AV8BC-410-100

Description and Operation - Cabin Cooling And Defog System

WP004 00

Alphabetical Index

Subject

Page No.

Anti-G System Component Locator, Figure 1

Anti-G System Schematic, Figure 2

Description

Component Description

Anti-G/Canopy Seal Check Valve

Anti-G/Canopy Seal Test Port

Anti-G Disconnect

Anti-G Valve

Rear Anti-G Disconnect

Rear Anti-G Valve

Related Systems

Cabin Cooling and Defog System

System Controls and Indicators

Manual Inflation Buttons

System Description

Operation

Component Operation

Anti-G/Canopy Seal Check Valve

Anti-G/Canopy Seal Test Port

Anti-G Disconnect

Anti-G Valve

Rear Anti-G Disconnect

Rear Anti-G Valve

System Operation

Automatic Mode

Ground Test

Manual Mode

A1-AV8BC-410-100

009 00

Page 2

Record of Applicable Technical Directives

Type/

Date

Title and ECP No.

Date Incorp.

Remarks

Number

AV8AFC-284

ANTI-G Valve Replacement (ECP MDC-

15 Oct 88

AV-8B-0131C1)

1. DESCRIPTION.

11. Cabin Cooling and Defog System. The cabin

cooling and defog system (WP004 00) provides air

2. SYSTEM DESCRIPTION. The anti-g system

pressure to the anti-g system. Air is tapped from a

automatically regulates air pressure to the

duct between the secondary heat exchanger and the

crewmembers anti-g suits to increase their tolerance

cold air unit expansion turbine inlet.

to high acceleration levels. The anti-g suit reduces

the fatiguing effect of repeated exposure to high

12. SYSTEM CONTROLS AND INDICATORS.

acceleration which can cause grayout or blackout

System controls and indicators are described in

because of lack of oxygen-rich blood to the brain.

paragraphs below.

The anti-g suit applies a regulated pressure to the

crewmembers lower torso to keep oxygen-rich blood

13. Manual Inflation Buttons. The manual

in the upper torso.

inflation buttons on the anti-g valve and rear anti-g

valve allow the crewmembers anti-g suits to be

3. COMPONENT DESCRIPTION. System

manually inflated. All other operation is

components shown in figure 1 are described and

automatically controlled and no indicators are

listed in paragraphs below.

provided.

14. OPERATION.

4. Anti-G Valve. The anti-g valve is a pressure

regulating valve made up of a demand valve, relief

15. COMPONENT OPERATION.

valve, and an activating weight.

16. Anti-G Valve. The anti-g valve is located in the

5. Anti-G Disconnect. The anti-g disconnect is a

pilot services panel assembly. The valve regulates

console mounted quick release disconnect.

air pressure to the crewmembers anti-g suit to no

more than 12 psi. The valve is automatically

6. Anti-G/Canopy Seal Check Valve. The

controlled by G forces on an activating weight in

anti-g/canopy seal check valve is an in line poppet

the valve or manually by pressing the manual

type check valve. The check valve is threaded at

inflation button. In the suit inflation condition, the

each end.

activating weight is pressed down by positive G

force which opens a demand valve allowing air

7. Anti-G/Canopy Seal Test Port. The

pressure to inflate the anti-g suit. When suit

anti-g/canopy seal test port is an in line capped tee

pressure is enough to counteract the G force on the

fitting.

activating weight, the demand valve closes and a

constant suit pressure is held during the G force

8. Rear Anti-G Disconnect. The rear anti-g

condition. When G force is reduced, the activating

disconnect is a console mounted, quick release

disconnect.

weight is moved up by spring tension and suit

pressure is exhausted to the cockpit. This condition

9. Rear Anti-G Valve. The rear anti-g valve is a

is held during suit exhaust and static conditions. A

pressure regulating valve made up of a demand

relief valve prevents anti-g valve outlet pressure

valve, relief valve, and an activating weight.

from exceeding 12 psi.

10. RELATED SYSTEMS. Related systems are

17. Rear Anti-G Valve. The rear anti-g valve is

described in paragraphs below.

located in the rear pilot services panel assembly.

The valve regulates air pressure to the

crewmembers anti-g suit to no more than 12 psi.

The valve is automatically controlled by G forces on

A1-AV8BC-410-100

009 00

Page 3

an activating weight in the valve or manually by

21. Anti-G/Canopy Seal Test Port. The

pressing the manual inflation button. In the suit

anti-g/canopy seal test port is located in the

inflation condition, the activating weight is pressed

forward end of the nose wheelwell. The test port

down by positive G force which opens a demand

allows a ground air source to be used for ground

valve allowing air pressure to inflate the anti-g suit.

testing of the anti-g system.

When suit pressure is enough to counteract the G

force on the activating weight, the demand valve

22. SYSTEM OPERATION.

closes and constant suit pressure is held during the

G force condition. When G force is reduced, the

23. Automatic Mode. Air pressure, tapped from

activating weight is moved up by spring tension and

the cabin cooling and defog system (WP004 00),

suit pressure is exhausted to the rear cockpit. This

passes through the anti-g/canopy seal check valve

condition is held during suit exhaust and static

(figure 2) to the anti-g valves. Positive G forces

conditions. A relief valve prevents anti-g valve

move an activating weight down opening a demand

outlet pressure from exceeding 12 psi.

valve allowing air pressure to inflate the anti-g suit.

When G forces decrease the activating weight is

18. Anti-G Disconnect. The anti-g disconnect,

moved up by spring tension closing the demand

located inboard of the pilot services panel assembly,

valve and opening an exhaust valve, allowing the

provides the quick disconnect interface between the

anti-g suit to deflate.

anti-g system and the crewmembers anti-g suit.

24. Manual Mode. Air pressure, tapped from the

19. Rear Anti-G Disconnect. The rear anti-g

cabin cooling and defog system (WP004 00), passes

disconnect, located inboard of the rear pilot services

through the anti-g/canopy seal check valve (figure

panel assembly, provides the quick disconnect

2) to the anti-g valves. Pressing the manual

interface between the anti-g system and the

inflation button moves an activating weight down

crewmembers anti-g suit.

opening a demand valve allowing air pressure to

inflate the anti-g suit. When the manual inflation

20. Anti-G/Canopy Seal Check Valve. The

button is released, the activating weight is moved

anti-g/canopy seal check valve is a one way check

up by spring tension, closing the demand valve and

valve. The valve is located in the air duct between

opening an exhaust valve, allowing the anti-g suit to

the secondary heat exchanger and the cold air unit

deflate.

expansion turbine inlet. The check valve will

prevent loss of anti-g system pressure if loss of

25. Ground Test. With a ground air source applied,

cabin cooling and defog system (WP004 00)

the anti-g system can be operated manually. The

pressure occurs. The check valve also isolates the

system operation is the same for ground test or

anti-g system so a ground air source can be used.

in-flight manual operation.

A1-AV8BC-410-100

010 00

Change 7 - 15 May 2004

Page 1

ORGANIZATIONAL MAINTENANCE

PRINCIPLES OF OPERATION

REAR EQUIPMENT COOLING SYSTEM

Reference Material

Electrical Systems

A1-AV8BB-420-100

AC Power System

WP003 00

DC Power System

WP004 00

Electrical Systems

A1-AV8BD-420-100

AC Power System

WP003 00

DC Power System

WP004 00

Lighting Systems

A1-AV8BB-440-100

Warning/Caution/Advisory Lighting System

WP007 00

Power Plant and Related Systems

A1-AV8BD-290-100

Basic Engine

WP003 00

Alphabetical Index

Subject

Page No.

Description

Component Description

Avionics Cooling Air Fittings

Rear ECS Air Filter Assembly

Rear ECS Air Inlet Temperature Switch

Rear ECS Check Valve

Rear ECS Cold Air Unit

Rear ECS Cold Air Unit Pressure Switch

Rear ECS Ground Cooling Fan

Rear ECS Ground Cooling Fan Pressure Switch

Rear ECS Ground Cooling Fan Speed Sensor

Rear ECS Ground Cooling Valve

Rear ECS Heat Exchanger

Rear ECS Pressure Reducing and Shutoff Valve

Rear ECS Temperature Control Valve

Rear ECS Temperature Sensor

Related Systems

AC Power System

DC Power System

Power Plant and Related Systems

Warning/Caution/Advisory Lighting System

System Controls and Indicators

AFT BAY Caution Light

EQUIP Switch

A1-AV8BC-410-100

010 00

Change 7

Page 2

Alphabetical Index (Continued)

Subject

Page No.

Rear Cool Fan Control Relay

Rear Equipment Bay Cooling Control Relay

60 Sec Delay ECS Relay

System Description

Operation

Component Operation

Avionics Cooling Air Fittings

Rear ECS Air Filter Assembly

Rear ECS Air Inlet Temperature Switch

Rear ECS Check Valve

Rear ECS Cold Air Unit

Rear ECS Cold Air Unit Pressure Switch

Rear ECS Ground Cooling Fan

Rear ECS Ground Cooling Fan Pressure Switch

Rear ECS Ground Cooling Fan Speed Sensor

Rear ECS Ground Cooling Valve

Rear ECS Heat Exchanger

Rear ECS Pressure Reducing and Shutoff Valve

Rear ECS Temperature Control Valve

Rear ECS Temperature Sensor

System Operation

Emergency/Ground Operation

Normal Operation

Rear Equipment Cooling System Component Locator, Figure 1

Rear Equipment Cooling System Simplified Schematic-162747; ALSO 162963 THRU 163861

BEFORE AV8AFC-416, Figure 2

Rear Equipment Cooling System Simplified Schematic-164113 AND UP; ALSO 162963 THRU

163861 AFTER AV8AFC-416, Figure 3

Record of Applicable Technical Directives

Type/

Date

Title and ECP or RAMEC No.

Remarks

Number

Incorp.

AV8AFC-354

30 Jun 94

Global Positioning System (GPS) Provisions

1 Mar 97

—

and Mini TACAN Incorporation of (ECP

MDC-AV8-0168C1)

AV8AFC-393

3 Sep 99

Addition of Digital Flap Controller (DFC)

15 May 99

—

(ECP MDC-AV8-00255R1)

AV8AFC-416

— TAV-8B Polyimide Wire Replacement/

15 May 04

—

Power Wire Separation (ECP MDA-AV8B-

0277)

A1-AV8BC-410-100

010 00

Change 6

Page 2A/(2B blank)

DESCRIPTION.

4. Avionics Cooling Air Fittings. Several different

types of fittings are used. Cooling requirements and

2. SYSTEM DESCRIPTION. Aft fuselage mounted

mounting provisions vary for different avionics

avionics equipment is cooled by the rear equipment

units. Some fittings are collapsible, self sealing

cooling system. Engine bleed air, extracted from the

assemblies. Others are duct flanges. Fittings may or

sixth stage of compression, is conditioned and

may not include filters and/or orifices.

distributed to the rack mounted avionics equipment

to provide required cooling.

5. Rear ECS Air Filter Assembly. The rear ECS air

filter assembly is a reusable, steel mesh filter

3. COMPONENT DESCRIPTION. System

element encased in a housing with a spring loaded

components shown in figure 1 are described and

bypass valve.

listed in paragraphs below.

A1-AV8BC-410-100

010 00

Change 7

Page 3

6. Rear ECS Air Inlet Temperature Switch. The

regulating section and shutoff valve section are

rear ECS air inlet temperature switch is a

made up of a piston sliding within a cylinder on a

temperature sensitive switch encased in a threaded

hollow shaft. The shutoff valve section piston is

housing.

spring loaded closed and the pressure regulating

section piston is spring loaded open. The pressure

7. Rear ECS Check Valve. The rear ECS check

regulating section also has a blowoff valve.

valve is a flapper type, in line, spring loaded closed,

check valve.

16. Rear ECS Temperature Sensor. The rear ECS

temperature sensor is a temperature sensitive

8. Rear ECS Cold Air Unit. The rear ECS cold air

control device made up of a body, a bimetallic

unit is an expansion turbine and axial flow fan,

temperature sensitive strip with a valve seat

mounted at opposite ends of a common shaft, in a

connected to one end, and an orifice adapter.

common housing. The unit has a serviceable bearing

lubrication system and a bearing cooling system.

17. Rear ECS Temperature Control Valve. The

rear ECS temperature control valve is a

9. Rear ECS Cold Air Unit Pressure Switch. The

pneumatically controlled and actuated flow control

rear ECS cold air unit pressure switch is a pressure

valve. The valve is made up of a body enclosing a

sensitive electrical switch encased in a threaded

spring-loaded double-action piston and hollow shaft

housing.

attached to a poppet valve and an orifice filter. The

valve is spring loaded closed.

10. Rear ECS Ground Cooling Fan. The rear ECS

ground cooling fan is an electrically driven axial

18. RELATED SYSTEMS. Related systems are

flow fan. The fan is made up of a flow impeller

described in paragraphs below.

mounted directly to the shaft of a 3 phase, 400 Hz

electrical motor. The motor and impeller are

19. Power Plant and Related Systems. Hot, high

enclosed in a housing with guide vanes built in on

pressure bleed air is provided by the engine sixth

the outlet end of the impeller. The motor has an

stage compressor (A1-AV8BD-290-100, WP003 00).

electrical sensing unit and overheat protection

devices.

20. DC Power System. The DC power system on

162747; ALSO 162963 THRU 163861 BEFORE

11. Rear ECS Ground Cooling Fan Pressure

AV8AFC-416 (A1-AV8BB-420-100, WP004 00) or

Switch. The rear ECS ground cooling fan pressure

164113 AND UP; ALSO 162963 THRU 163861

switch is a pressure sensitive electrical switch

AFTER AV8AFC-416 (A1-AV8BD-420-100, WP004

encased in a threaded housing.

00) provides 28vdc essential power for the rear

equipment cooling system.

12. Rear ECS Ground Cooling Fan Speed Sensor.

The rear ECS ground cooling fan speed sensor is an

21. AC Power System. The AC power system on

electronic processing unit in a sealed case.

162747; ALSO 162963 THRU 163861 BEFORE

AV8AFC-416 (A1-AV8BB-420-100, WP003 00) or

13. Rear ECS Ground Cooling Valve. The rear

164113 AND UP; ALSO 162963 THRU 163861

ECS ground cooling valve is a two position

AFTER AV8AFC-416 (A1-AV8BD-420-100, WP003

pneumatically actuated and controlled valve. The

00) provides essential 115vac for the rear equipment

valve is made up of a housing which contains a

cooling system.

piston attached to a spring loaded diaphragm that

controls a hinged valve.

22. Warning/Caution/Advisory Lighting System.

The warning/caution/advisory lighting system

14. Rear ECS Heat Exchanger. The rear ECS heat

(A1-AV8BB-440-100, WP007 00) provides visual

exchanger is a single pass, cross flow, air to air heat

indication of normal aircraft functions and system

exchanger. The heat exchanger is made up of a

malfunctions affecting safety of flight operations.

finned core inside a welded housing.

The warning/caution/advisory lighting system

includes the annunciator light controller and the

15. Rear ECS Pressure Reducing and Shutoff

caution/advisory indicator light assembly. The

Valve. The rear ECS pressure reducing and shutoff

annunciator light controller receives data from

valve is a solenoid controlled pressure regulating

various aircraft systems and provides logic to turn

and shutoff valve in a single unit. Both the pressure

on and off warning/caution/advisory lights.

A1-AV8BC-410-100

010 00

Page 4

23. The annunciator light controller will turn on

deenergized, essential 115vac is applied to the rear

the AFT BAY caution lights and the MASTER

ECS ground cooling fan.

CAUTION lights when the rear equipment cooling

system is off.

33. Rear Equipment Bay Cooling Control Relay.

The rear equipment bay cooling control relay,

24. SYSTEM CONTROLS AND INDICATORS.

located on the distribution panel assembly, is a dual

System controls and indicators are described in

pole, double throw, 5 amperes, permanent magnet

paragraphs below.

drive, armature relay.

25. EQUIP Switch. The EQUIP switch, located on

34. The relay is controlled by the rear ECS air inlet

the ECS control panel assembly, is a dual pole

temperature switch or the rear ECS cold air unit

toggle switch. The switch provides electrical control

pressure unit switch. With the relay energized, the

for the rear ECS pressure reducing and shutoff

following occurs:

valve. The switch has three positions: RESET, ON,

and OFF. The switch must be held in RESET.

a. Essential 28vdc power is applied to energize

the rear ECS pressure reducing and shutoff valve

26. Setting the EQUIP switch to ON applies

solenoid.

essential 28vdc power to contacts of the rear

equipment bay cooling control relay.

b. Essential 28vdc power is removed from the

annunciator light controller to enable the AFT BAY

27. Setting the EQUIP switch to OFF applies

caution lights.

essential 28vdc power to a contact of the rear

equipment bay cooling control relay and energizes

35. With the relay deenergized, the following

the rear ECS pressure reducing and shutoff valve

occurs:

solenoid. Energizing the solenoid closes the valve.

Power applied to rear equipment bay cooling

a. Essential 28vdc power is removed to

control relay contacts with the EQUIP switch ON is

deenergize the rear ECS pressure reducing and

removed with the EQUIP switch OFF.

shutoff valve solenoid.

28. Setting and holding the EQUIP switch to

b. Essential 28vdc power is applied to the

RESET removes essential 28vdc power from the

annunciator light controller to disable the AFT

rear equipment bay cooling control relay contact

BAY caution lights.

and from the rear ECS pressure reducing and

shutoff valve solenoid, opening the valve.

36. 60 Sec Delay ECS Relay. The 60 sec delay ECS

relay, located on the aft relay panel assembly is a

29. AFT BAY Caution Lights. The AFT BAY

time delay, 10 amperes, dual pole, double throw,

caution lights, located on the caution/advisory

armature. The relay contacts move 60 seconds after

indicator light assembly and the rear

the relay is energized. When deenergized, the

caution/advisory indicator light assembly are yellow

contacts move immediately.

lens, dual lamp, indicator lights.

37. The relay is controlled by the rear ECS cold air

30. The AFT BAY caution lights are controlled by

unit pressure switch. With the relay energized,

the rear ECS air inlet temperature switch, or the

essential 28vdc power is applied to the input of the

rear ECS cold air unit pressure switch, through the

rear ECS air inlet temperature switch. With the

warning/caution/ advisory lighting system.

relay deenergized, essential 28vdc power is removed

from the input of the rear ECS air inlet

31. Rear Cool Fan Control Relay. The rear cool fan

temperature switch.

control relay, located on the distribution panel

assembly, is a four pole, double throw, 5 amperes,

38. OPERATION.

permanent magnet drive, armature relay.

39. COMPONENT OPERATION.

32. The relay is controlled by the rear ECS ground

cooling fan pressure switch. With the relay

40. Avionics Cooling Air Fittings. Avionics cooling

energized, essential 115vac is removed from the rear

air fittings, located on the equipment cooling rack,

ECS ground cooling fan. With the relay

provide the cooling system interface between rack

A1-AV8BC-410-100

010 00

Page 5

mounted equipment and the equipment rack. When

and sent by way of ducting to mix with hot air from

a unit is installed on the equipment rack, it makes

the rear ECS temperature control valve.

contact with a cooling air fitting. The fitting makes

a seal between the unit and the rack, allowing

45. During ground operation, the driven axial flow

cooling air to flow through the unit. Some fittings

fan draws ram air across the rear ECS heat

contact the unit on the back and some contact the

exchanger. The ram air then exits through the ram

bottom, depending on unit mounting. The different

air exhaust.

types of fittings used are required for the different

cooling requirements of each unit.

46. Lubrication for the common shaft is provided

41. Rear ECS Air Filter Assembly. The rear ECS

by oil stored in a cotton wool pack sump and

air filter element assembly is located in the MLG

transported to the shaft by a system of oil wicks.

wheelwell. Sixth stage engine bleed air is sent by

The sump has fill and drain plugs located to allow

way of ducting to the filter assembly. The filter

periodic servicing of oil while the unit is still in the

removes particulate contamination before it can

aircraft.

cause damage further downstream in the rear

equipment cooling system. If the filter element

47. Shaft bearing cooling is provided by a tube,

becomes blocked, pressure build up opens a bypass

tapped into the ram air inlet, which transports

valve allowing air to bypass the filter element. The

cooling air to the shaft bearings.

bypass valve opens at 4 psid. The filter element is

replaceable independent of the housing or may be

48. Rear ECS Cold Air Unit Pressure Switch. The

cleaned and reused. With the element removed, the

rear ECS cold air unit pressure switch is located in

housing allows a ground air source to be adapted

the rear ECS cold air unit expansion turbine inlet

and used for ground operational checkout.

duct. When turbine inlet pressure exceeds 72 psi,

the pressure switch closes and applies essential

42. Rear ECS Air Inlet Temperature Switch. The

28vdc to energize the rear equipment bay cooling

rear ECS air inlet temperature switch is located in

control relay. When turbine inlet pressure decreases

the equipment cooling shelf supply duct. If

to below 72 psi, the switch opens to enable the rear

equipment cooling air exceeds 131°F, the

equipment bay cooling control relay to be manually

temperature switch closes and applies essential

reset. After an overpressure occurs, the system must

28vdc to energize the rear equipment bay cooling

be manually reset, using the EQUIP switch located

control relay. When equipment cooling air decreases

on the ECS control panel assembly.

to less than 130°F, the temperature switch opens to

enable the rear equipment bay cooling control relay

49. Rear ECS Ground Cooling Fan. The rear ECS

to be manually reset. After an overheat occurs, the

ground cooling fan is located in a duct tapped from

system must be manually reset, using the EQUIP

the rear ECS ram air inlet in door 61. With the fan

switch located on the ECS control panel assembly.

operating, air is pulled in through the rear ECS ram

air inlet. The cooling air is given a high velocity by

43. Rear ECS Check Valve. The rear ECS check

the fan impeller and is transported by way of

valve is located in the left hand rear equipment

ducting to the equipment cooling rack. The fan will

cooling system exhaust duct. The check valve

operate when electrical power is applied and rear

prevents reverse airflow from being induced into the

equipment cooling system pressure is less than 5.0

system during ground operation. The check valve

psi.

also prevents the ingestion of foreign objects into

the system.

50. The guide vanes straighten the airflow before

44. Rear ECS Cold Air Unit. The rear ECS cold air

discharge from the fan. The electrical sensing unit

unit is located at the base of the rear ECS heat

provides an electrical signal to the rear ECS ground

exchanger in door 61. The expansion turbine

cooling fan speed sensor based on fan speed. The

receives pre-cooled air from the rear ECS heat

overheat protection devices will automatically stop

exchanger. Heat energy is converted to mechanical

the fan, if an overheat condition occurs. When the

energy by spinning the expansion turbine. The

overheat condition no longer exists, the fan will

turbine drives the axial flow fan through the

resume normal operation. The fan motor is cooled

common shaft. With the heat lost, cold air is left

by its own airflow.

A1-AV8BC-410-100

010 00

Page 6

51. Rear ECS Ground Cooling Fan Pressure

duct in door 61. The heat exchanger initially cools

Switch. The rear ECS ground cooling fan pressure

sixth stage engine bleed air for use in the rear

switch is located in the rear ECS heat exchanger

equipment cooling system. The engine bleed air

outlet duct in door 61. When system pressure is

enters the heat exchanger core and is cooled by ram

greater than 5.0 psi the switch does the following:

air forced across the core by aircraft forward

motion. During ground operation, ram air is pulled

a. Applies essential 28vdc to energize the rear

across the core by the axial flow fan of the rear ECS

cooling fan control relay.

cold air unit. The partly cooled bleed air is then

sent to the turbine section of the rear ECS cold air

b. Applies essential 28vdc to disable the AFT

unit. In the heat exchanger core, the engine bleed

BAY caution lights.

air makes two passes, the cooling air makes only

one pass.

c. Removes essential 28vdc from the rear ECS

ground cooling fan speed sensor. When system

55. Rear ECS Pressure Reducing And Shutoff

pressure is less than 5.0 psi, the switch does the

Valve. The rear ECS pressure reducing and shutoff

following:

valve is located in the engine bleed air supply duct,

in the MLG wheelwell. The valve assembly encloses

d. Removes essential 28vdc to deenergize the

a small solenoid operated valve and provides a

rear cooling fan control relay.

flange for the attachment of the valve solenoid. The

solenoid is energized by essential 28vdc to close the

e. Applies essential 28vdc to the rear ECS

valve and deenergized to open the valve. This valve,

ground cooling fan speed sensor.

which is spring loaded, controls two ports, one

opening to atmosphere and the other to system

f. Removes essential 28vdc to enable the AFT

pressure; the spring keeps the port to atmosphere

BAY caution lights.

open and the other port shut. The body also

52. Rear ECS Ground Cooling Fan Speed Sensor.

encloses the assembly which controls the shutoff

The rear ECS ground cooling fan speed sensor is

and regulating functions, and also has a safety

located on the left side of the rear equipment bay in

valve, inlet and outlet connection. The shutoff valve

door 61. The speed sensor receives an electrical

is spring loaded and free to slide over a fixed

signal from the rear ECS ground cooling fan

cylinder located by a hollow shaft. This shaft carries

electronic sensing unit. The signal is proportional to

a collar over which slides a spring loaded sleeve,

fan rotational speed. If the signal received by the

which controls the regulating function by varying

speed sensor is within a predetermined limit, the

the size of the annular port based on the system

speed sensor will complete an electrical circuit and

demand. Various drillings in the assembly allows

allow avionics ground power to be applied. If the

atmospheric pressure or system pressure to enter

signal is out of limits, the speed sensor will inhibit

the space between the shutoff valve and the

application of power to the avionics equipment.

cylinder (depending on the position of the

controlling valve) and system pressure only to the

53. Rear ECS Ground Cooling Valve. The rear

rest of the assembly.

ECS ground cooling valve is located on the rear

ECS ram air inlet duct in door 61. When air

56. If an electrical system failure occurs, the rear

pressure is applied to the valve (rear equipment

ECS pressure reducing and shutoff valve will move

cooling system operating normally), the spring

to the open (deenergized) position.

loaded diaphragm is compressed and the valve is

held closed. When air pressure is lost (rear

57. Rear ECS Temperature Sensor. The rear ECS

equipment cooling system shutdown), the spring

temperature sensor is located in the equipment

force moves the piston to open the valve. The valve,

cooling supply duct, in door 61. The sensor senses

with the rear ECS ground cooling fan, allows

air temperature and adjusts the rear ECS

ambient air to flow and cool aircraft equipment for

temperature control valve to provide the required

ground operation and inflight if a cooling system

temperature. The sensor bi-metal strip is connected

failure occurs.

to the inside of the sensor body so the valve seat

fits centrally on the face of the orifice adapter. The

54. Rear ECS Heat Exchanger. The rear ECS heat

orifice adapter is connected to an air connection of

exchanger is located in the rear ECS ram air inlet

the rear ECS temperature control valve. An increase

A1-AV8BC-410-100

010 00

Page 7

or decrease in sensed temperature causes the

turbine inlet pressure is too high, the rear ECS cold

bi-metal strip to deflect and move the valve seat on

air unit pressure switch will energize the rear

to, or off of the orifice adapter. The change in air

equipment bay cooling control relay. The energized

pressure in the rear ECS temperature control valve

relay applies power to energize the rear ECS

control chamber moves the valve open or closed as

pressure reducing and shutoff valve solenoid. The

required to provide the required temperature.

valve will then close. Emergency/ground operation

will then start.

58. Rear ECS Temperature Control Valve. The

rear ECS temperature control valve is located in a

61. The cooled air from the rear ECS cold air unit

hot air bypass duct between the engine bleed air

expansion turbine is mixed with hot engine bleed

duct and the equipment cooling supply duct in door

air from the secondary circuit through the rear ECS

61. The valve mixes hot engine bleed air with

temperature control valve. The mixed air is then

conditioned air to provide the required air

sent through the rear ECS temperature sensor. The

temperature for equipment cooling. With the rear

sensor will control the rear ECS temperature

equipment cooling system off, spring pressure holds

control valve and maintain the correct mixture of

the poppet valve closed. With the system operating,

hot and cooled air. The air then passes to the

engine bleed air passes through the hollow shaft

equipment cooling rack, where the temperature is

and orifice filter to the control chamber. During

monitored by the rear ECS air inlet temperature

normal operation, pressure will increase in the

switch. If air temperature is too hot, the switch

control chamber. When control chamber pressure

closes and energizes the rear equipment bay cooling

increases to a point greater than spring tension, the

control relay. The energized relay applies power to

valve will open. When the rear ECS temperature

energize the rear ECS pressure reducing and shutoff

sensor senses the air temperature is too hot, control

valve solenoid. The valve will then close.

chamber pressure is lost and the valve will move

Emergency/ground operation will then start.

toward closed.

62. Emergency/Ground Operation. On the ground

59. SYSTEM OPERATION.

with the engine not running, or inflight and rear

equipment cooling system pressure is lost or system

60. Normal Operation. Sixth stage engine bleed

shut down, the rear ECS ground cooling fan (figure

air is routed to the rear ECS air filter assembly

2) will operate and cool the equipment. When

(figure 2) where particulate contaminates are

system pressure is lost or low, the rear ECS cooling

removed. The bleed air is then sent to the rear ECS

valve opens and the rear ECS ground cooling fan

pressure reducing and shutoff valve where pressure

pressure switch trips. The switch deenergizes the

is regulated to approximately 75 psi. The regulated

rear cool fan control relay. The deenergized relay

air then passes through a flow limiting venturi and

applies power to the rear ECS ground cooling fan

is then divided into two circuits. The main circuit

and allows cooling air to be pulled through the rear

flows through the rear ECS heat exchanger where

ECS ground cooling valve by the rear ECS ground

the air temperature is reduced through exchange

cooling fan. The fan forces air through the

with ram air. The conditioned air is then sent to the

equipment cooling rack.

expansion turbine section of the rear ECS cold air

unit, where it is again cooled by rapid expansion.

63. The AFT BAY caution lights will be on if

The spinning turbine drives an axial flow fan on a

system pressure is too high as sensed by the rear

common shaft in the rear ECS cold air unit, which

ECS cold air unit pressure switch, or if system

pulls more ram air across the rear ECS heat

temperature is too high as sensed by the rear ECS

exchanger. If the rear ECS cold air unit expansion

air inlet temperature switch.

A1-AV8BC-410-100

010 00

Change

Page

Nomenclature

Index No.

Ref Des

AC ESSENTIAL PANEL ASSEMBLY

52A-N131

REAR COOL FAN (ZONE C5)

22CBN010

REAR COOL FAN (ZONE D5)

22CBN011

REAR COOL FAN (ZONE E5)

22CBN012

TERMINAL BOARD

52TBN139

60 SECOND DELAY ECS RELAY

22K-N056

REAR COOL FAN CONTROL RELAY

22K-N013

ANNUNCIATOR LIGHT CONTROLLER

27A-D007

AFT RELAY PANEL ASSEMBLY

52A-P016

60 SEC DELAY ECS RELAY

22K-P056

CAUTION/ADVISORY INDICATOR LIGHT

27A-F011

ASSEMBLY AFT BAY CAUTION LIGHT

COMPUTER CP-1293/ALR-67(V) COOLING AIR

—

OUTLET

DC ESSENTIAL/MAIN PANEL ASSEMBLY

52A-P133

ECS REAR (ZONE D4)

22CBP001

REAR EQUIPMENT COOLING CONTROL

22K-P004

RELAY

DIGITAL DATA COMPUTER COOLING AIR

—

FITTING

DISTRIBUTION PANEL ASSEMBLY

52A-N025

ECS REAR (ZONE B7)

22CBN001

REAR COOL FAN (ZONE C7)

22CBN010

REAR COOL FAN (ZONE D7)

22CBN011

REAR COOL FAN (ZONE E7)

22CBN012

TERMINAL BOARD

52TBN091

REAR EQP BAY COOLING CONTROL RELAY

22K-N004

REAR COOLING FAN CONTROL RELAY

22K-N013

ECS CONTROL PANEL ASSEMBLY

22A-F048

EQUIPMENT SWITCH

22S-F003

FLAP ELECTRONIC CONTROLLER COOLING AIR

—

FITTING

DIGITAL FLAP CONTROLLER COOLING AIR FIT-

—

TING

FLIGHT CONTROL COMPUTER CP-1743/

—

ASW-46(V) COOLING AIR FITTING

GENERATOR CONTROL UNIT COOLING AIR FIT-

—

TING

Figure 1. Rear Equipment Cooling System Component Locator (Sheet

11)

A1-AV8BC-410-100

010 00

Change

Page

Nomenclature

Index No.

Ref Des

RADIO-RECEIVER TRANSMITTER RT-1159/A

—

COOLING AIR OUTLET

REAR CAUTION/ADVISORY INDICATOR LIGHT

27A-H045

ASSEMBLY

AFT BAY CAUTION LIGHT

REAR ECS AIR FILTER ASSEMBLY

22FAT517

REAR ECS AIR INLET TEMPERATURE SWITCH

22S-N006

REAR ECS CHECK VALVE

22VAN523

REAR ECS COLD AIR UNIT

22MAP519

REAR ECS COLD AIR UNIT PRESSURE SWITCH

22S-N008

REAR ECS GROUND COOLING FAN

22B-N014

REAR ECS GROUND COOLING FAN PRESSURE

22S-P009

SWITCH

REAR ECS GROUND COOLING FAN SPEED

22A-N049

SENSOR

REAR ECS GROUND COOLING VALVE

22MAP522

REAR ECS HEAT EXCHANGER

22MAP518

REAR ECS PRESSURE REDUCING AND SHUTOFF

22L-T005

VALVE

REAR ECS TEMPERATURE CONTROL VALVE

22MAN520

REAR ECS TEMPERATURE SENSOR

22MAN521

SIGNAL DATA CONVERTER CV-3736/A COOLING

—

AIR FITTING

STORES MANAGEMENT COMPUTER CP-1451/

—

AYQ-13 COOLING AIR FITTING

LEGEND

162747; ALSO 162963 THRU 163861 BEFORE AV8AFC-416.

164113 AND UP; ALSO 162963 THRU 163861 AFTER AV8AFC-416.

BEFORE AV8AFC-354.

BEFORE AV8AFC-393.

AFTER AV8AFC-393.

Figure 1. Rear Equipment Cooling System Component Locator (Sheet 12)

A1-AV8BC-410-100

011 00

Change 7 - 15 May 2004

Page 1

ORGANIZATIONAL MAINTENANCE

PRINCIPLES OF OPERATION

DESCRIPTION AND OPERATION

ON-BOARD OXYGEN GENERATING SYSTEM

Reference Material

Ejection Seat and Canopy System

A1-AV8BB-120-100

Description - Ejection Seat System

WP003 00

Environmental Control System

A1-AV8BC-410-100

Component Locator - On-Board Oxygen Generating System

WP012 00

Power Plant and Related Systems

A1-AV8BD-290-100

Basic Engine

WP003 00

Electrical Systems

A1-AV8BB-420-100

DC Power System

WP004 00

Electrical Systems

A1-AV8BD-420-100

DC Power System

WP004 00

Lighting Systems

A1-AV8BB-440-100

Warning/Caution/Advisory Lighting System

WP007 00

Alphabetical Index

Subject

Page No.

Description

Component Description

Mixer/Diffuser Duct

OBOGS Bleed Air Shutoff Valve

OBOGS Heat Exchanger

OBOGS Heat Exchanger Ejector Filter

OBOGS Overtemperature Switch

OBOGS Pressure Relief Valve

OBOGS Test Port

Oxygen Concentrator GGU-7/A

Oxygen Disconnect

Oxygen Monitor Assembly CRU-91/A

Oxygen Monitor Assembly CRU-99/A

Oxygen Plenum

Rear Oxygen Disconnect

Rear Oxygen Plenum

Related Systems

Basic Engine

A1-AV8BC-410-100

011 00

Change 7

Page 2

Alphabetical Index (Continued)

Subject

Page No.

DC Power System

Ejection Seat System

Warning/Caution/Advisory Lighting System

System Controls and Indicators

OBOGS O Temp Indicator

OEAS Htr Cont Rly

OXY Caution Lights

OXY Shutoff Valve

OXY Switch

System Description

On-Board Oxygen Generating System Simplified Schematic-TAV-8B 162747; ALSO 162963

THRU 163861 BEFORE AV8AFC-416, Figure 1

On-Board Oxygen Generating System Simplified Schematic-TAV-8B 164113 AND UP; ALSO

162963 THRU 163861 AFTER AV8AFC-416, Figure 2

Operation

Component Operation

Mixer/Diffuser Duct

OBOGS Bleed Air Shutoff Valve

OBOGS Heat Exchanger

OBOGS Heat Exchanger Ejector Filter

OBOGS Overtemperature Switch

OBOGS Pressure Relief Valve

OBOGS Test Port

Oxygen Concentrator GGU-7/A

Oxygen Disconnect

Oxygen Monitor Assembly CRU-91/A or CRU-99/A

Oxygen Plenum

Rear Oxygen Disconnect

Rear Oxygen Plenum

System Operation

Emergency Operation

Normal Operation

Record of Applicable Technical Directives

Type/

Date

Title and ECP or RAMEC No.

Remarks

Number

Incorp.

AV8AFC-416

— TAV-8B Polyimide Wire Replacement/

15 May 04

—

Power Wire Separation (ECP MDA-AV8B-

0277)

1. DESCRIPTION.

remaining gas is an oxygen rich breathing mixture

for crewmembers.

2. SYSTEM DESCRIPTION. The on-board oxygen

generating system (OBOGS) removes nitrogen and

other contaminants from engine bleed air. The

A1-AV8BC-410-100

011 00

Change 7

Page 3

3. COMPONENT DESCRIPTION. System

sensor, processing electronics, built-in test (BIT), a

components are described and listed in paragraphs

circuit heater and a pressure controlled sensing

below. For component locator, refer to WP012 00.

chamber.

4. OBOGS Bleed Air Shutoff Valve. The OBOGS

14. Oxygen Monitor Assembly CRU-99/A. The

bleed air shutoff valve is a motor driven, butterfly

oxygen monitor assembly CRU-99/A is a solid state

type shutoff valve. The valve is made up of an

electronic processor. The monitor is made up of

actuator, electric drive motor, limit switches, a

processing electronics, two built-in test (BIT)

housing, and an external position indicator.

buttons, a circuit heater and a pressure controlled

sensing chamber.

5. OBOGS Heat Exchanger. The OBOGS heat

exchanger is a cross-flow air to air heat exchanger.

15. Oxygen Disconnect. The oxygen disconnect is

The heat exchanger is made up of a tubular core,

a console mounted, quick release disconnect.

ejector, and ejector filter enclosed in a stainless

steel case. The heat exchanger case is wrapped with

16. Rear Oxygen Disconnect. The rear oxygen

insulation.

disconnect is a console mounted, quick release

disconnect.

6. OBOGS Heat Exchanger Ejector Filter. The

OBOGS heat exchanger ejector filter is an in-line

17. OBOGS Test Port. The OBOGS test port is an

wire mesh filter. The filter element is brazed to a

in-line, capped, tee fitting.

threaded cap. The filter can be cleaned and

replaced independent of the OBOGS heat

18. RELATED SYSTEMS. Related systems are

exchanger.

described in paragraphs below.

7. Mixer/Diffuser Duct. The mixer/diffuser duct is

19. Ejection Seat System. The ejection seats

a stainless steel machined duct.

(A1-AV8BB-120-100, WP003 00) have an

emergency oxygen cylinder stored in each survival

8. OBOGS Pressure Relief Valve. The OBOGS

kit. The emergency oxygen supply can be manually

pressure relief valve is an in-line, mechanical,

actuated if OBOGS is off or fails, or automatically

pressure relief valve.

actuated during emergency egress.

9. OBOGS Overtemperature Switch. The OBOGS

20. Basic Engine. The engine (A1-AV8BD-290-100,

overtemperature switch is a sealed, bi-metallic

WP003 00) provides hot, eighth stage compressor

electrical switch designed into a threaded plug for

bleed air to the on-board oxygen generating system.

in-line mounting.

21. DC Power System. The DC power system on

10. Oxygen Concentrator GGU-7/A. The oxygen

162747; ALSO 162963 THRU 163861 BEFORE

concentrator GGU-7/A is an electrical/mechanical

AV8AFC-416 (A1-AV8BB-420-100, WP004 00) or

device. The concentrator is made up of a rotary

164113 AND UP; ALSO 162963 THRU 163861

valve, two molecular sieve beds, drive/servo motor,

AFTER AV8AFC-416 (A1-AV8BD-420-100, WP004

temperature control circuit, plenum assembly, air

00) provides emergency and main 28vdc power to

heater, inlet filter, pressure reducer, and an

the on-board oxygen generating system.

insulating shroud.

22. Warning/Caution/Advisory Lighting System.

11. Oxygen Plenum. The oxygen plenum is an

The warning/caution/advisory lighting system

in-line, 100 cubic inch, aluminum storage cylinder.

(A1-AV8BB-440-100, WP007 00) provides visual

indication of normal aircraft functions and system

12. Rear Oxygen Plenum. The rear oxygen plenum

malfunctions affecting safety of flight operations.

is an in-line, 100 cubic inch, aluminum storage

The warning/caution/advisory lighting system

cylinder.

includes the annunciator light controller and the

caution/advisory indicator light assembly. The

13. Oxygen Monitor Assembly CRU-91/A. The

annunciator light controller receives data from

oxygen monitor assembly CRU-91/A is an electronic

various aircraft systems and provides logic to turn

processor. The monitor is made up of an oxygen

on and off warning/caution/advisory lights.

NATOPS FLIGHT MANUAL NAVY MODEL AV--8B/TAV--8B 161573 AND UP AIRCRAFT (2008) - page 13