Ground controlled approach
The ground-controlled approach ( ground-controlled approach , short GCA ) is a in the aviation used radar-controlled, down to run blind approach procedures, which in World War II was developed and is still on failure of avionics in the aircraft there as a reserve landing aid option.
Working method
GCA uses panoramic radar to guide the landing aircraft into a position that allows an approach to the runway being used, as well as a precision approach radar aligned along the runway that tracks the aircraft as it approaches. The operating team of the radar gives the pilot of the approaching aircraft control instructions via radio that allow him to land on a virtual glide path to the runway even in instrument flight without visibility .
The final approach radar in the GCA uses two antennas, one covering a vertical sector and the other covering a horizontal area. In addition to the instructions for the descent, the pilot is also given information / instructions relating to his position in relation to the extended center line of the runway. The work of the air traffic controller who monitors the final approach is to enable the pilot to carry out an approach that is equivalent to an ILS approach by making appropriate corrections to the direction and rate of descent .
history
GCA was developed during the Second World War in an American-British collaboration in order to be able to safely land bombers returning from enemy flights over continental Europe even in poor visibility.
The British Gatow airfield in West Berlin was equipped with a GCA system as early as 1945. It was a crucial technical skill for the operation of the closely-timed Berlin Airlift .
Science fiction writer Arthur C. Clarke , who worked on these radar systems during the war, fictionalized the story of GCA's development in his novel Glide Path .
Individual evidence
- ^ Jan Behrendt & Doris Müller-Toovey: The Berlin-Gatow airfield. A forgotten place of memory? in: The Berlin Airlift. Cold War memorial site (edited by Corine Defrance, Bettina Greiner & Ulrich Pfeil), Berlin 2018, p. 226.