What is ADF (Automatic Direction Finder)?

What is ADF (Automatic Direction Finder)?

• A. A lightweight airborne system that operates in the GPS band.
• B. A satellite navigation system.
• C. A lightweight airborne system that operated in the UHF/VHF frequency 100 to 400 MHz range.
• D. A radar altimeter.

Answer: (C)

ADF is a lightweight airborne navigation aid that determines the aircraft’s bearing to a ground radio beacon. It uses a directional receiver and an antenna arrangement to sense the beacon’s signal and displays the direction to that beacon in the cockpit. The idea is to "home in" on a station, which helps you navigate by keeping the aircraft on a bearing toward or away from the beacon. This kind of system is distinct from GPS or satellite navigation and from radar altimeters, which serve different functions. The description that fits best is a compact onboard radio direction-finding system operating in the VHF/UHF range (100–400 MHz), used to derive bearing to a beacon for navigation.

ADF is a lightweight airborne navigation aid that determines the aircraft’s bearing to a ground radio beacon. It uses a directional receiver and an antenna arrangement to sense the beacon’s signal and displays the direction to that beacon in the cockpit. The idea is to "home in" on a station, which helps you navigate by keeping the aircraft on a bearing toward or away from the beacon. This kind of system is distinct from GPS or satellite navigation and from radar altimeters, which serve different functions. The description that fits best is a compact onboard radio direction-finding system operating in the VHF/UHF range (100–400 MHz), used to derive bearing to a beacon for navigation.