Definition
A descriptor for an instrument, indicator, or piece of avionics equipment that contains its own internal battery as a backup power source, allowing it to continue operating for a limited period if the aircraft's primary electrical system fails.
Plain English
The instrument has its own small battery inside it, so it keeps working for a while even if the aircraft loses electrical power.
Context Anchor
Seen in instrument flying discussions about backup instruments, standby displays, and equipment that must keep working during an electrical problem.
Why Pilots Care
Provides critical backup power for instruments during alternator or generator failure, supporting continued safe flight under IFR.
Intuition Check
Do not read this as meaning only that the aircraft has a battery. Here, battery equipped means the specific instrument or system has battery power available to run it.
Example Sentence 1
The standby attitude indicator is battery equipped, so it will continue to display attitude for at least thirty minutes after a complete electrical failure.
Example Sentence 2
Battery-equipped aircraft can maintain attitude reference after an alternator failure long enough to reach VMC.