Definition
Unwanted electrical disturbance, radiated or conducted from one electronic device, that disrupts the normal operation of another. In aircraft, electromagnetic interference can cause erratic indications, navigation errors, or radio noise when energy from one system couples into the wiring or circuitry of another.
Plain English
Stray electrical signals from one piece of equipment that mess with how another piece of equipment works.
Context Anchor
Pilots may encounter this term when troubleshooting radio noise, unreliable electronic indications, headset buzzing, or equipment problems caused by nearby electrical devices or wiring.
Derivation
From 'electromagnetic' (relating to the combined electric and magnetic fields produced by moving electric charges) and 'interference' (something that gets in the way). Together: electrical energy that gets in the way of equipment trying to do its job.
Why Pilots Care
It can cause loss of reliable communications or navigation, creating safety risks in flight.
Analogy
It is like trying to listen to a quiet conversation while someone nearby runs a blender. The blender is not aimed at you, but its noise still drowns out what you are trying to hear.
Grounding Statement
In the cockpit, electromagnetic interference often shows up as noise in the headset, a weak or distorted signal, or electronic equipment that behaves abnormally near another electrical source.
Intuition Check
Interference here does not mean something is physically blocking a part. It means unwanted electrical or radio energy is disturbing a signal or electronic device.
Example Sentence 1
The mechanic suspected electromagnetic interference from the new strobe power supply was causing the static heard on the comm radio.
Example Sentence 2
Proper shielding of the wiring prevented electromagnetic interference from affecting the instruments.