What does the term 'empty weight' refer to in aviation?

The term 'empty weight' in aviation accurately refers to the weight of the airplane without any fuel. Specifically, it encompasses the aircraft structure, systems, and all fixed equipment but excludes any usable or non-usable fuel. Understanding empty weight is crucial for pilots as it forms the baseline from which the weight and balance calculations are made.

This concept is significant because it impacts the aircraft's performance, such as its takeoff distance and load-carrying capacity. When pilots determine the maximum weight they can carry (taking into account passengers, cargo, and fuel), knowing the empty weight helps ensure the aircraft operates within safe limits.