In aviation a ground-controlled approach (GCA), is a type of service provided by air-traffic controllers whereby they guide aircraft to a safe landing in adverse weather conditions based on radar images. Most commonly a GCA uses information from either a Precision Approach Radar (PAR, for precision approaches with vertical, glide path guidance) or an Airport Surveillance Radar (ASR, providing a non-precision Surveillance Radar Approach with no glide path guidance). Technically, the term GCA applies specifically to the precision radar approach with glide path guidance.
Read more about Ground-controlled Approach: Overview
Famous quotes containing the word approach:
“Oh! mystery of man, from what a depth
Proceed thy honours. I am lost, but see
In simple childhood something of the base
On which thy greatness stands; but this I feel,
That from thyself it comes, that thou must give,
Else never canst receive. The days gone by
Return upon me almost from the dawn
Of life: the hiding-places of man’s power
Open; I would approach them, but they close.”
—William Wordsworth (1770–1850)