Definition
A maintenance procedure used to restore residual magnetism in the field frame of a generator or the field poles of a starter-generator. A momentary direct current is applied to the field winding in the correct polarity, leaving behind enough residual magnetism for the unit to begin generating voltage on its next start.
Plain English
Briefly sending battery current through a generator's field coils to leave a small amount of magnetism behind, so the generator can start producing electricity again.
Context Anchor
Seen in aircraft electrical system maintenance when a generator does not build voltage after installation, overhaul, or long storage.
Derivation
Flashing' here comes from the brief, momentary nature of the current pulse — a quick flash of electricity through the field, not a sustained connection. 'The field' refers to the field winding, the coil that creates the magnetic field inside the generator.
Why Pilots Care
Restores generator output to maintain battery charging and electrical system function during flight.
Intuition Check
Flashing here does not mean a blinking light, and field does not mean a grassy area. It means a brief current pulse into the magnetic part of the generator.
Example Sentence 1
After the generator failed to come online during run-up, the technician flashed the field and the system began producing voltage normally.
Example Sentence 2
After extended storage the mechanic flashed the field to restore residual magnetism before reinstalling the generator.