Definition
The downward force exerted on an airplane due to gravity acting on its mass, including the airframe, fuel, occupants, and cargo. Weight acts vertically toward the center of the earth and must be balanced by lift for the airplane to maintain level flight.
Plain English
How heavy the airplane is — the pull of gravity on everything in and on it. This downward pull is one of the four forces acting on the airplane in flight, and lift has to match it to stay level.
Context Anchor
Seen in final approach, landing performance, and weight-and-balance discussions, especially when deciding whether the airplane is at a safe weight for landing and what speed or distance to expect.
Derivation
From Old English wiht, meaning 'amount that something weighs.' In aviation, the word keeps its plain meaning but is treated as a force — the result of gravity acting on mass — rather than just a number on a scale.
Why Pilots Care
Weight directly determines required lift, stall speed, and the approach speed needed for a safe landing.
Intuition Check
Do not think of weight as only the airplane’s empty weight. In this context, weight means the airplane plus everything aboard at that moment. Do not confuse weight with balance. Weight is how heavy the airplane is; balance is where that weight is located.
Example Sentence 1
On final approach, the pilot adjusted the approach speed to account for the airplane's lighter weight after burning off fuel during the flight.
Example Sentence 2
Reducing aircraft weight by burning off fuel lowers the stall speed for landing.