Plain English Meaning
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.
Full 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.
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.