What is the definition of maximum zero fuel weight?

The definition of maximum zero fuel weight is the maximum allowable weight of an aircraft when it is loaded with passengers, cargo, and unusable fuel, excluding any usable fuel. This weight limit is crucial for ensuring that the aircraft remains within safe operating parameters, particularly in terms of structural integrity and flight performance. It is primarily concerned with the weights carried within the aircraft’s airframe rather than the weight of the fuel that could be added for flight.

Understanding this concept is particularly important for weight-and-balance calculations, as exceeding the maximum zero fuel weight can affect stability and performance, especially during takeoff and landing phases. Other definitions, such as maximum takeoff weight and maximum landing weight, pertain to different phases of flight and include fuel in their calculations, which is why they do not represent the same concept as maximum zero fuel weight.