Definition
A weather and terrain detection system installed in an aircraft that transmits radio energy from an antenna, usually mounted in the nose, and displays the reflected returns to show the location and intensity of precipitation, storm cells, and in some systems, terrain ahead of the aircraft.
Plain English
A radar carried in the aircraft itself that lets the pilot see weather, especially heavy rain and thunderstorms, in the airspace ahead so it can be avoided.
Context Anchor
Seen in instrument flying and weather avoidance discussions, especially when planning a route around thunderstorms or heavy precipitation.
Derivation
Radar comes from RAdio Detection And Ranging. Airborne simply means carried on the aircraft, as opposed to radar based on the ground. Together it means a radar carried by and operated from the aircraft.
Why Pilots Care
Allows real-time detection of hazardous weather during flight, enabling route changes that reduce turbulence encounters and improve safety.
Intuition Check
Do not assume airborne radar shows all bad weather. It shows radar returns, especially from precipitation, and the pilot uses those returns as clues about where the most hazardous weather may be.
Example Sentence 1
The crew used airborne radar to pick a path between two building cells well before reaching them.
Example Sentence 2
Before departure the crew checked the airborne radar for any returns indicating convective activity along the planned route.