Definition
The total downward force exerted on an airplane by gravity, equal to the mass of the airframe, fuel, occupants, cargo, and any other onboard items multiplied by the acceleration of gravity. Weight acts vertically downward through the aircraft's center of gravity and must be opposed by lift for the airplane to remain airborne.
Plain English
How heavy the airplane is at any given moment, including everything on board. Gravity pulls all of that weight straight down, and the wings have to produce enough lift to hold it up.
Context Anchor
Seen in discussions of energy management, takeoff and landing planning, climb performance, turns, and loading the airplane before flight.
Derivation
“Weight” comes from an old word meaning heaviness. In aviation, it helps to remember that weight is not just a listed amount; it is the airplane’s downward pull due to gravity.
Why Pilots Care
Aircraft weight determines the lift required to fly, directly influencing takeoff distance, climb rate, stall speed, and landing distance.
Intuition Check
Do not think of aircraft weight as only baggage or cargo. It includes the airplane itself, fuel, people, baggage, and equipment, and it acts as a downward pull that the wings must support.
Example Sentence 1
After loading the passengers and topping off the fuel, the pilot confirmed the aircraft weight was below the maximum allowed for takeoff.
Example Sentence 2
As fuel burned during the cross-country flight, the aircraft weight decreased and climb performance improved.