Chapter 12 - Fuel Flashcards
What is max fuel capacity on the 747-400?
359,414 lbs
(359,400)
How many fuel tanks on the 747-400?
- 7 total
- 4 Main tanks 1,2,3,4
- 2 Reserve tanks 2,3
- 1 Center tank
- The horizontal tank is decommissioned.
Where is fuel tank temperature taken?
Main Tank 1
What tank does the APU take fuel from when operating?
Main tank 2
EICAS fuel imbalances (quantity) messages for:
- Main tanks 1 & 4?
- Main tanks 2 & 3?
- Fuel Imbalance?
3000 LBS between tanks 1 and 4
6000 LBS between tanks 2 and 3
6000 LBS between INBOARD and OUTBOARD tanks
How many fuel pumps do the Main outboard tanks have?
2 Main pumps
How many fuel pumps do the Main inboard tanks have?
Main 2
5
- 2 main pumps
- 2 OVRD/JETTISON pumps
- 1 APU DC pump
Main 3
4
- 2 main pumps
- 2 OVRD/JETTISON pumps
Which pumps have the most pressure?
CWT OVRD/JETTISON pumps
What does FUEL TANK/ENG indicate and what is the crew action?
Displays when inboard main tank is equal to or less than the outboard main tank
The crew action is to…
- Push off the 2 & 3 OVRD pumps
- Close X-FEED valves 1 & 4
On aircraft with an electric scavenge pump, when is the pump commanded to operate? Where does the scavenged fuel go? How long will it operate?
• Scavenge commences at reserve tank 2 and 3 transfer initiation.
• Fuel is discharged into number 2 main tank
• The pump operates for 120 minutes or until low pressure is sensed.
When will the fuel system automatically balance itself?
Automatic balancing of the fuel system is accomplished during fuel jettison ONLY, by the fuel jettison control system.
What is the difference between total fuel and calculated fuel? When are the values different
• Total fuel is the fuel sensed in the tanks.
• Calculated fuel separates from total fuel when the first engine is started. It uses engine fuel flow subtracted from the fuel sensed at engine start.
On taxi out, the EICAS advisory message “FUEL IMBAL 1-4” is displayed. What does this mean?
Can you depart?
You configure the crossfeed manifold and fuel pumps to bring the fuel imbalance to 2,800 pounds. Is the message still displayed?
Can you depart?
• The EICAS advisory indicates a fuel difference between main tanks 1 and 4 of 3,000 pounds or more.
• No.
• The message will still be displayed, because it will not disappear until the difference is less than 1,000 pounds.
• Yes, the limitation is 3,000 pounds.
You are overweight for landing and must land. Fuel jettison is required. Per the QRH procedure, you arm jettison system by selecting jettison controller A.
How do you know the system is armed for fuel jettison?
After entering your desired fuel remaining, ATC asks you how long you will be jettisoning fuel.
How can you provide the information?
• Arming of the fuel jettison system is indicated by an outline of the jettison manifold being displayed on the secondary EICAS Fuel Synoptic Page.
• The jettison time will be displayed on the upper right corner of the Fuel Synoptic Page 90 seconds after jettison is commenced.
You are jettisoning fuel using jettison controller A. Jettison controller A fails.
What happens?
• Jettison will terminate and the EICAS message ”>FUEL JETT A” will display
• Jettison controller B must be selected manually
What is the purpose of the 1 and 4 transfer valves?
• They are used during fuel jettison
• They are used in a non-normal procedure if both boost pumps fail in either the number 1 or 4 main tank.
You are fully configured for takeoff. What are the positions of the number 2 and 3 crossfeed valves?
What are the cockpit indications?
• The crossfeed valves are closed.
• The flow bars in the crossfeed switches are visible.
What does the careted EICAS message “>FUEL OVD CTR L” mean?
• On the ground, more than 17,000 pounds of fuel is in the center wing tank and the left override/jettison pump is OFF
• In cruise, more than 4,000 pounds of fuel is in the center wing tank and the left override/jettison pump is OFF