Definition
The maximum allowable weight of passengers, cargo, and baggage that an aircraft can carry, calculated as the maximum takeoff weight minus the empty weight and minus the weight of the minimum required fuel and oil. It represents the largest load the aircraft is approved to carry, before fuel above the minimum is added.
Plain English
The most weight in people, bags, and cargo the aircraft is allowed to carry once you've subtracted what the aircraft itself weighs and the smallest legal amount of fuel and oil it needs.
Context Anchor
Seen in weight and balance planning, especially when deciding how many people, bags, cargo, and how much fuel can be carried before takeoff.
Derivation
From Old French paie ("to pay") + load — historically the portion of a load that paid for the trip (passengers and cargo), as opposed to fuel and the aircraft itself. Knowing this helps separate "payload" (what you're carrying for a purpose) from total aircraft weight.
Why Pilots Care
Exceeding this limit reduces climb performance, increases takeoff distance, and can make the aircraft unsafe or illegal to fly.
Intuition Check
Do not assume maximum payload capacity means the airplane can carry that payload with full fuel. Fuel has weight, and adding fuel may reduce the payload you can take.
Example Sentence 1
After checking the loading chart, the pilot realized the bags and three passengers were within the maximum payload capacity, but adding full fuel would push the aircraft over its takeoff weight limit.
Example Sentence 2
With full fuel the airplane’s maximum payload capacity dropped to three passengers and light luggage.