Precision runway monitor
This article does not cite any sources. (March 2013) (Learn how and when to remove this template message)
PRM is one type of radar system that can be used to allow simultaneous approaches on parallel runways that are spaced less than 1,310 metres (4,300 ft) to each other. Airports at which PRM is in use in the United States include Chicago-O'Hare, San Francisco, Detroit, and Atlanta. Internationally only Sydney, Australia uses PRM.
Additionally, flight crew wishing to fly PRM approaches are required to undergo specific training related to these approaches before taking part. The training includes practicing the climbing and descending “BREAKOUT” manoeuvre in the simulator.