FAA Aircraft Dispatcher (ADX)Flight Planning and PerformanceEasy
A dispatcher is reviewing the weight and balance limits for a transport category aircraft. What does the Maximum Zero Fuel Weight (MZFW) represent?
- AThe maximum weight including taxi fuel prior to engine start
- BThe maximum weight authorized at brake release for takeoff
- CThe maximum weight at which the aircraft may land at any airport
- DThe heaviest weight permitted for the aircraft structure with no usable fuel aboard; any additional weight must be added as fuel
Show answer & explanationAnswer & explanation
Correct answer: D. The heaviest weight permitted for the aircraft structure with no usable fuel aboard; any additional weight must be added as fuel
MZFW is a structural limit representing the maximum weight of the aircraft, payload, and everything except usable fuel. Fuel loaded beyond MZFW is limited by wing bending relief, so any weight above MZFW up to MTOW/MLW must be fuel.
Why the other options are wrong
- A. This describes Maximum Ramp/Taxi Weight.
- B. This describes Maximum Takeoff Weight (MTOW).
- C. This describes Maximum Landing Weight (MLW), not MZFW.
Maximum Zero Fuel Weight (MZFW)
The maximum permissible weight of the aircraft and its payload without usable fuel, a structural limit protecting the wing/fuselage from excessive bending loads.
- Weight beyond MZFW must be usable fuel
- Fuel in wings provides bending relief, reducing wing root stress
- Exceeding MZFW even briefly can cause structural damage
- Distinct from MTOW (takeoff) and MLW (landing) limits
Memory trick: Zero Fuel = Zero relief for the wings, so payload alone can't exceed it