Definition
A steady electrical voltage or current applied to a circuit, component, or instrument to set its baseline operating point. In electronics, bias establishes the reference condition from which the device responds to incoming signals. In aviation instruments and systems, a bias voltage or bias signal is added to shift a reading or hold a component in a desired state.
Plain English
A small, constant push (electrical or mechanical) applied to something so it sits at the right starting point before it does its real job.
Context Anchor
Seen in aircraft electrical, radio, instrument, and avionics discussions, especially when explaining how electronic circuits are set up to operate.
Derivation
From Old French 'biais' meaning 'slant' or 'oblique angle.' The idea carried into English as a steady leaning in one direction — which fits the technical use: a steady voltage that leans the circuit toward a chosen operating point.
Why Pilots Care
Uncorrected bias can produce incorrect airspeed, altitude, or heading information that affects navigation and safety decisions.
Intuition Check
Bias does not mean an unfair opinion here. In this context, it means a deliberate electrical setting that gives a circuit the starting condition it needs.
Example Sentence 1
The technician adjusted the bias voltage on the amplifier so the signal sat in the middle of its operating range.
Example Sentence 2
Pilots apply a known bias correction when the directional gyro begins to drift after several hours of flight.