Definition
The total electrical demand placed on an aircraft's power source (battery and/or generator/alternator) by all operating equipment at a given moment, measured in amperes. It includes everything drawing current — avionics, lights, pitot heat, fuel pumps, instruments, and any other powered systems.
Plain English
How much electrical power the aircraft's equipment is using right now. The more items switched on, the higher the load.
Context Anchor
Seen when operating on the main battery, especially after an alternator or generator failure, when the pilot must decide which electrical equipment to keep on and which to turn off.
Derivation
Load' comes from Old English 'lad,' meaning a burden or what is carried. In electrical use, it refers to what the power source has to 'carry' — the demand placed on it. The heavier the load, the harder the battery or generator works.
Why Pilots Care
When operating on battery alone, a high electrical load drains the battery faster and shortens the time available for essential systems.
Analogy
Think of a battery like a water tank and each electrical item like a faucet. The more faucets you open, the faster the tank runs down.
Intuition Check
Do not read “load” here as cargo weight or passenger weight. In this context, it means the amount of electrical demand placed on the aircraft’s power system.
Example Sentence 1
After the alternator failed, the pilot reduced the electrical load by switching off non-essential lights and avionics to preserve battery power.
Example Sentence 2
With the alternator failed, the crew monitored electrical load to decide which instruments to keep powered.