What is zero fuel weight (ZFW)?

Zero fuel weight (ZFW) refers to the weight of the aircraft without any usable fuel on board. This weight includes the aircraft's structure, payload, and any non-fuel related items, such as cargo and passengers. Understanding ZFW is crucial for flight planning and safety as it helps in calculating the aircraft's balance and center of gravity once fuel is added for the flight.

The other options fail to accurately define ZFW. ZFW does not include fuel; therefore, it cannot represent the maximum weight before loading cargo or the weight including usable fuel. It typically does not focus solely on passengers either, as ZFW encompasses all non-fuel related components.