Definition
A radar-based instrument approach in which a controller on the ground watches the aircraft's position on radar and gives the pilot continuous verbal instructions for heading and descent all the way to the runway. It includes a precision approach using precision approach radar (PAR), where the controller provides glide path and course corrections, or a surveillance approach using airport surveillance radar (ASR), where only course and recommended altitudes are given.
Plain English
A landing approach where a controller watches the aircraft on radar and talks the pilot down to the runway, telling them what heading to fly and when to descend.
Context Anchor
Used during instrument flying, especially when a pilot is approaching an airport in low visibility and is receiving close guidance from air traffic control.
Derivation
The name describes the procedure literally: the approach is controlled from the ground rather than flown using onboard navigation equipment. The pilot follows spoken instructions from a radar controller instead of reading instruments tied to ground-based signals or satellite guidance.
Why Pilots Care
Provides a reliable backup landing method when onboard navigation fails or weather prevents visual or ILS approaches.
Grounding Statement
The pilot hears step-by-step heading and altitude instructions from a controller watching the aircraft on a ground radar screen.
Intuition Check
Do not read “controlled” as meaning the airplane is flown from the ground. In a GCA, the pilot flies the airplane; the controller gives spoken guidance.
Example Sentence 1
With the onboard navigation equipment unreliable, the pilot requested a GCA and followed the controller's headings and descent calls down to the runway.
Example Sentence 2
During the GCA, the controller issued heading corrections every few seconds to keep the aircraft aligned with the runway.