Ground controlled approach

Ground Controlled Approach (GCA): A radar landing system operated from the ground by air traffic control personnel transmitting instructions to the pilot by radio.
Holding Apron: (see holding bay) ...

GCA - ground controlled approach. A landing approach in which a ground controller gives verbal guidance in azimuth and elevation to a pilot using precision approach radar (PAR) to monitor the aircraft's approach path.

PAR (GCA Ground Controlled Approach) Approach Only at some military fields.
This approach is a highly-skilled, labour intensive system being shut down by the military.

AN/MPN-14 Mobile Ground Approach System can configured as a complete Radar Approach Control (RAPCON) or Ground Controlled Approach (GCA) facility.

See also: Radar, GCA, Navigation, Runway, Direct