Definition
A method of navigation in which a ground-based radar facility tracks an aircraft's position and provides vectors, position information, or guidance to the pilot via radio. The controller sees the aircraft as a target on a radar display and issues headings, altitudes, and other instructions to navigate the aircraft along a desired course or to a specific point.
Plain English
Someone on the ground watches your aircraft on a radar screen and tells you which way to fly. You follow their instructions instead of navigating from the cockpit on your own.
Context Anchor
Encountered in instrument flying when a controller gives radar vectors, position updates, or guidance toward an airport or runway.
Derivation
Radar comes from RAdio Detection And Ranging -- a system that uses radio waves to detect objects and measure how far away they are. 'Ground-based' simply means the radar equipment sits on the ground (at an ATC facility) rather than in the aircraft.
Why Pilots Care
It enables safe navigation and traffic separation in low visibility or controlled airspace without relying solely on onboard equipment.
Intuition Check
Do not read “ground-based” as meaning the aircraft is flying close to the ground. It means the radar equipment is located on the ground and the pilot receives guidance from a controller.
Example Sentence 1
Approach control used ground-based radar navigation to vector the flight onto the final approach course.
Example Sentence 2
During the instrument approach, the pilot followed ground-based radar navigation instructions to maintain the assigned heading.