An autopilot can be controlled by the pilot or can be coupled to what kind of signal?

• A. A radio navigation signal
• B. ATC data link
• C. GPS signal only
• D. Inertial reference signal

Answer: (A)

Autopilots are designed to follow guidance from external signals, not just operate on internal controls. A radio navigation signal provides defined guidance that the autopilot can lock onto to maintain a course, follow a localizer, or track a glideslope. This capability lets the aircraft fly along established routes or approaches without pilot input. While GPS is a navigation source that can be used in some systems, it’s only one type of radio navigation signal, and the broader category includes other signals like VOR and ILS that are commonly used to couple the autopilot to an exact course. ATC data link is for communications rather than a steering cue, and an inertial reference signal comes from the aircraft’s own navigation system rather than an external guidance source used to control the autopilot.