FAA Aircraft Dispatcher (ADX)Flight Planning and PerformanceMedium
An aircraft departs at 178,000 pounds but must return immediately due to smoke in the cabin. Maximum landing weight is 150,000 pounds, and the fuel jettison rate is 2,000 pounds per minute. How many minutes of fuel dumping are required to reach maximum landing weight?
- A10 minutes
- B16 minutes
- C14 minutes
- D28 minutes
Show answer & explanationAnswer & explanation
Correct answer: C. 14 minutes
Excess weight = 178,000 − 150,000 = 28,000 pounds. At 2,000 lb/min, time required = 28,000 ÷ 2,000 = 14 minutes.
Why the other options are wrong
- A. Incorrect division of excess weight.
- B. Incorrect result of the division.
- D. This is the excess weight in pounds, not the time in minutes.
Fuel Jettisoning (Dumping)
The controlled release of fuel in flight to reduce aircraft weight to at or below maximum landing weight before an immediate landing.
- Required time = excess weight ÷ jettison rate
- Used when landing weight would otherwise exceed structural limits
- Not all aircraft are equipped with jettison systems
Memory trick: Dump the difference, not the whole tank.