FAA Aircraft Dispatcher (ADX)Flight Planning and PerformanceHard
A cargo pallet weighing 400 pounds is moved 30 feet forward in an aircraft with a total weight of 60,000 pounds. How far and in which direction does the center of gravity shift?
- A2.0 feet forward
- B0.5 foot forward
- C0.2 foot forward
- D0.1 foot forward
Show answer & explanationAnswer & explanation
Correct answer: C. 0.2 foot forward
CG shift = (weight moved × distance moved) ÷ total aircraft weight = (400 × 30) ÷ 60,000 = 12,000 ÷ 60,000 = 0.2 foot forward, since the weight moved toward the nose.
Why the other options are wrong
- A. 2.0 feet is off by a factor of 10 from the correct calculation.
- B. 0.5 foot would result from an incorrect total weight or distance value.
- D. 0.1 foot understates the shift; the correct numerator (12,000) divided by 60,000 gives 0.2.
CG Shift Formula
When weight is shifted within an aircraft, the CG shift distance equals (weight moved × distance moved) divided by total aircraft weight.
- Formula: CG shift = (weight shifted × distance shifted) ÷ total weight
- Direction of CG shift matches direction weight was moved
- Used for load shifts, not for adding/removing weight
Memory trick: 'Move the load, share the shift — divide by the whole to get the drift.'