132. GCA
GCA（ground controlled approach） は、 捜 索 レ ー ダ ー （ASR ／ airport surveillance radar）， 精 測 レ ー ダ ー（PAR ／ precision approach radar）および無線機により構成される。 GCA による進入では、管制官が無線により誘導すること から、航空機側では航法用機上装置によることなく計器進 入を行うことができる。 [225],[235],[636]
132. ＧＣＡ
A radar approach system, in which an aircraft approach may be directed by ATC close to the landing threshold thorough radio communications, is called GCA (Ground Controlled Approach). GCA is classified in the ASR approach, wherein distance and azimuth information are provided, and the PAR approach wherein glide path information is provided in addition to distance and azimuth information. [636] An advantage of the GCA is that an aircraft is merely required a communication device for conducting an instrument approach.
a. ASR (Airport Surveillance Radar) approach:
A nonprecision instrument approach wherein an air traffic controller issues instructions for pilot compliance based on aircraft position in relation to the final approach course
