surveillance approach

An instrument approach in which a radar controller provides navigational guidance in azimuth only. The airport surveillance radar (ASR) furnishes the pilot headings to fly to align the aircraft with the extended centerline of the landing runway. Considering the lower accuracy levels of the surveillance approach versus a precision approach, higher minimums apply. The ASR cannot provide guidance in elevation to the pilot but it does advise him or her when to commence the descent to the minimum descent altitude (MDA) or, if appropriate, to an intermediate step-down fix, minimum-crossing altitude, and subsequently to the prescribed MDA. In addition, it advises the pilot of the location of the missed approach point (MAP) prescribed for the procedure and the aircraft’s position each mile on the final approach to the runway, airport, heliport, or MAP, as appropriate. If the pilot requests it, recommended altitudes are issued at each mile, based on the descent gradient established for the procedure, down to the last mile that is at or above the MDA. Normally, the ASR provides navigational guidance until the aircraft reaches the MAP. Controllers will terminate guidance and instruct the pilot to execute a missed approach unless at the MAP the pilot has the runway, airport, or heliport in sight or, for a helicopter point-in-space approach, the prescribed visual reference with the surface is established. Also, if at any time during the approach the controller considers that safe guidance for the remainder of the approach cannot be provided, he or she will terminate guidance and instruct the pilot to execute a missed approach. Similarly, guidance termination and the missed approach will be effected upon pilot request. For civil aircraft only, controllers may terminate guidance when the pilot reports the runway, airport, heliport, or visual surface route (point-in-space approach) is in sight or otherwise indicates that continued guidance is not required. Radar service is automatically terminated at the completion of a radar approach.