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fuel_dumping_imageIn case of emergency, all internal, external and CFT fuel (except for fuel in engine feed tanks) can be dumped overboard from an outlet located at the right wingtip (see figure below). Note that engine feed tanks cannot be dumped.



- Fuel dumping outlet
- Fuel dump piping
- Fuel vent box
- Internal wing tank (forward section)
- Integral wing tank (aft section)

When fuel dump is selected, a motor-operated dump valve in the right integral wing tank opens. When this valve is open, fuel transfer pumps in tank 1 and in internal wing tanks (4, 5) force the fuel to pass through the fuel dump piping (2) towards the the fuel dumping outlet (1) which lets the fuel dumped overboard into the air. External fuel cannot be dumped when the landing gear is down, while internal and CFT dumping is not dependent on the position of the landing gear.

Fuel in conformal fuel tanks and external tanks is transferred into tank 1 and in the integral wing tanks and then is dumped from there. If tank 1 and internal wing tanks transfer pumps fail, external fuel passes through a fuel check valve and is dumped.

Approximate fuel dumping rate is 390 lbs/min for the right internal wing tank, 260 lbs/min for the left internal wing tank and 1,260 lbs/min for tank 1. This gives a total dumping rate of 910 lbs/min. The uneven dumping rates of the internal tanks (wing tanks and tank 1) cause a fuel imbalance of approximately 130 lbs/min. This imbalance can cause up to 1,100 lbs weight difference between the left and right side of the aircraft (left wing is heavier) and remains until all internal wing tanks become empty.

Pilot Controls

The aircraft's fuel management systems can be controlled by switches on the fuel panel, located forward on the pilot left side console (see figure below). The switches and their functions are discussed below.


- Fuel control switch: external wing tanks
- Fuel control switch: centerline tank
- Fuel control switch: conformal tank
- Fuel dump switch
- CFT emergency transfer switch
- External transfer switch
- Slipway switch

The three fuel control switches (1, 2, 3) control transfer and refuel procedures of all external tank types: external wing tanks (WING), centerline tank (CTR) and conformal fuel tanks (CFT). Their functions are discussed in details in article External Fuel Tanks.

The CFT emergency transfer switch (5) is used in emergency situations to transfer CFT fuel. Its functions are discussed in details in article Conformal Fuel Tanks.

The external transfer switch (6) is used to to schedule external fuel transfer. Its functions are discussed in details in article External Fuel Tanks.

The slipway switch (7) controls the aerial refueling receptacle door. Its functions are discussed in details in article Air Refueling System.

The fuel dump switch (4) is used to dump fuel. It is spring-loaded to the lever-locked NORM position. Fuel dump starts when the switch is placed into its DUMP position, where it is electrically held (with BINGO caution off). Dumping will continue until STOP TRANS is selected in the fuel control switches or (in case of external drop tanks) the landing gear is dropped. Placing the fuel dump switch back to its NORM position also stops dumping. During dumping if a BINGO caution comes up, then the fuel dump switch automatically returns to its NORM position, thus stopping dumping. Fuel dumping automatically stops when only engine feed tank fuel remains - this can occur if the bingo bug is set below approximately 2,700 lbs of fuel.


  • F-15E Flight Manual (TO 1F-15E-1) C 15 August 1990, courtesy of eFlightManuals

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Last Updated on Wednesday, 08 September 2010

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