Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Boeing 747 > Fuel > Flashcards

Fuel Flashcards

1
Q

EICAS color indications of fuel pump status

A

White - pump off
Green - pump on
Amber - pump low pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How many fuel tanks?

A
  • 4 x main tanks (1,2,3,4)
  • center wing tank
  • 2 x reserve tanks (2,3)
  • surge tanks in outer portion of each wing
  • horizontal stab tank with surge tank in outboard portion (pax)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many fuel pumps?

A
  • 8 x AC powered main tank pumps (2 per main tank)
  • 4 x AC powered override/jettison pumps (2 each for main tank 2 and 3)
  • 2 x Center Wing Tank (CWT) pumps (override/jettison)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Main and Override pump pressure capability

A

Main Pumps
- each pump can provide enough fuel for 1 engine during TO or 2 engines during cruise

Override/Jettison Pumps

  • each pump can provide enough fuel for 2 engine during TO and cruise
  • higher output than main pumps
  • center wing pumps are Override/Jettison pumps
  • horizontal stab tank pumps are override/jettison pumps (Pax)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Fuel Tank Capacities

A 
Main 1 and 4: 26,576 kg (13.3 ea)
Main 2 and 3: 76,263 kg (38.1 ea)
Center: 52,167 kg
Reserves: 8,036 kg (4.0 ea)
Stab Tank (pax): 10,030 kg

Total (freight): 163,042 kg
Total (pax): 173,072 kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When does fuel transfer from Reserve Tanks to Main tanks 2 or 3?

A
  • each reserve tank has two transfer valves
  • via gravity fuel transfers when main tank 2 or 3 drop below 18,200 kg
  • transfer valves can be open manually (RSV 2 and 3 XFER) or automatically by system logic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which tank is normal/backup source for APU fuel?

A
  • Main tank 2 supplied by main pump 2 aft
  • Bankup is Main pump 3 aft
  • DC pump in main tank 2 for APU battery start
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How is fuel system logic managed?

A

2 x Fuel System Management Cards (FSMCs) command fuel valves and pumps open or closed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is fuel jettisoned from the tanks?

A
  • Fuel Jettison selector rotated out of OFF position
  • Jettison Nozzle Valve On
  • Override/Jettison pumps (Main 2 and 3, CWT) pump fuel from all fuel tanks overboard
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What causes a FUEL IMBALANCE EICAS message?

A
  • imbalance between Main 1 and 4 of 1,360 kg
  • imbalance between Main 2 and 3 of 2,720 kg
  • message is removed when difference less than 450 kg
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is Fuel Quantity and Fuel Temperature measured?

A
  • Fuel Quantity sensor in each tank

- Fuel Temp sensors in main tank 1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is fuel flow displayed in the Fuel Synoptic page

A
  • Fuel flow is simulated based upon the pump status and valve positions
  • may no represent actual system operation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How is fuel management controlled?

A

2 x Fuel System Management Cards (FSMCs)

  • fuel valves open or closed based on logic
  • fuel pumps ON or OFF based on logic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which fuel pumps are on with the APU Running prior to engine start?

A

Main tanks 2 and 3 (PRESS light will be off)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How many surge tanks per wing?

A
  • one surge tank per wing
  • provide fuel surge relief and tank venting
  • no controls or indications to flight crew
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How many Fuel Crossfeed Valves

A
  • 4 x Fuel Crossfeed Valves in fuel manifold

- fuel can be delivered from any Main Tank or CWT to any engine or APU

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where is the Defuel Panel located?

A
  • overhead maintenance panel

- not normally used by flight crew

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Scavenge System

A
  • 4 scavenge pumps in CWT
  • ensure all fuel from CWT to Main Tanks 2 and 3
  • no control or indications
  • begins when main tank 2 or 3 decrease to approx 27,200 kgs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How is Fuel Balanced between tanks?

A
  • opening and closing of Crossfeed valves

- turning ON or OFF of specific pumps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Where is Fuel system information displayed?

A
  • Primary EICAS

- FUEL synoptic page

21
Q

Color indications for pumps on FUEL synoptic page?

A

White - OFF
Green - ON
Amber - Low Press
Cyan - Armed for System logic (override pumps)

22
Q

What would cause Fuel Main tank quantity to display in Amber?

A
  • imbalance condition

- less than 900 kg (2000 lbs)

23
Q

Fuel Density of usable fuel at level attitude

A

0.8 kgs per liter

24
Q

How much capacity can each AC Main pump support?

A
  • one engine at Takeoff Thrust; or

- two engines at cruise thrust

25
Q

How much capacity can each override/jettison support?

A
  • two engines at takeoff or cruise thrust
26
Q

What fuel quantity can override/jettison pumps 2 and 3 operate until?

A

Until standpipe level of approx 3,200 kg (7,000 lbs)

  • avoids jettison of all fuel
27
Q

Which pumps have priority over all others?

A

CWT override/jettison pumps override all other pumps

  • OJPs 2 and 3 are inhibited
  • One CWT pump will not inhibit or override
28
Q

Can engine receive fuel if fuel pump pressure is low?

A
  • Suction feed line to each engine, which bypasses fuel pumps
  • at hight altitudes reduced thrust or engine flameout may occur (dissolved air restricting fuel flow)
29
Q

How is each fuel pump activate?

A

Main pumps - manually via Main pump switch ON

Override/jettison pumps - system logic with switch ON

30
Q

When does fuel transfer from Main tanks 1 and 4 to Main tanks 2 and 3?

A
  • one transfer valve in each of Main tank 1 and 4
  • not a normal operation
  • Manually via FUEL XFER MAIN 1 and 4
  • automatically during fuel jettison when 2 and 3 tanks drop below 9,072 kg
  • fuel transfers via gravity
  • transfers to approx 3,200 kg in each outboard main tank
31
Q

When should the CWT pump switches be ON during normal flight ops?

A

When CWT has 7,700 kgs or more of fuel

32
Q

> FUEL TANK/ENG EICAS message

A
  • Fuel in main tank 2 is equal or less than main tank 1
  • Fuel in main tank 3 is equal or less than main tank 4

Actions:

1) Manually turn #2 and #3 OVRD pumps OFF
2) Manually CLOSE cross feeds #1 and #4

33
Q

Which pumps provide jettison fuel pressure?

A
  • override/jettison pump 2 and 3 and CWT OJPs
34
Q

When is Fuel Jettison prohibited?

A

With flaps in TRANSIT between 1 and 5

35
Q

How many jettison control systems?

A

2 (A or B)

36
Q

What kind of fuel supply?

A

Tank to engine

37
Q

When does fuel temperature indication turn amber?

A

-37º C and below

38
Q

Which tanks is fuel jettisoned from?

A

All tanks via Main tanks 2 and 3 and CWT

39
Q

What EICAS indication do you get when FUEL JETTISON selector is out of OFF (A or B)

A

Fuel to remain (TO REMAIN) replaces fuel temp

40
Q

With fuel tanks full what pumps are supplying engine during start?

A

Both Center Wing OJPs

41
Q

Fuel Pump/Cross-feed valve configuration with Flaps Set for Takeoff (Center tank over 7,700 kg of fuel)

A

CWT pumps ——> Engines 1 and 4
Main pumps 2 ——> Engine 2
Main pump 3 ——> Engine 3
Cross-feed valves 2 and 3 ——>closed

42
Q

Fuel Pump/Cross-feed valve configuration with Flaps Set for Takeoff (Center tank less than 7,700 kg of fuel)

A 
Override/jettison pump 2 ——> engine 1
Override/jettison pump 3 ——> engine 4
Main pump 2 ——> engine 2
Main pump 3 ——> engine 3
Cross-feed valves 2 and 3 ——> closed
43
Q

Fuel Pump/Cross-feed valve configuration with Flaps Up after Takeoff (Center Tank On)

A

CWT Override/Jettison pumps ——> all engines

All cross-feed valves ——> open

44
Q

Fuel Pump/Cross-feed valve configuration with Flaps Up after Takeoff (Center tank pumps off)

A

Override/jettison pumps 2 ——> ENG 1 and 2
Override/jettison pumps 3 ——> ENG 3 and 4
Cross-feed valves 2 and 3 ——> Open

45
Q

FUEL LOW CTR L, R EICAS Message

A
  • CWT less than 7,700 kgs before start with pump ON
  • CWT approx 3,200 kg in climb with pump ON
  • CWT approx 1,300 kg in cruise with pump ON
46
Q

What happens to the fuel quantity indication upon termination of fuel jettison?

A
  • fuel to remain changes colors from magenta to white and flashes for 5 secs
47
Q

What is the impact of an excessive fuel imbalance on the aircraft?

A

Adversely affects:

  • CG
  • aerodynamic drag
  • fuel economy
48
Q

When is an engine on suction feed, and how are suction feed situation corrected?

A
  • suction feed begins when main tank pressure is low

- corrected by opening appropriate cross-feed valves to obtain pressure from a main tank with operations pumps

Boeing 747 (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions