Precision runway monitor

II The prevalence ofdelay in scheduled airline flights in recent years has caused great interest in the use ofnew technologies that promise increased airport capacity, especially in poor weather. One consequence ofthis interest in new technologies is development ofthe Precision Runway Monitor (PRM) system. The PRM system uses enhanced radar and display capabilities combined with automatic safety alerts to allow safe operation ofindependently sequenced approaches, in instrument meteorological conditions, to parallel runways separated by less than 4300 feet (the current minimum separation without PRM). During the past several years, Lincoln Laboratory has carried out a development program for the PRM that has included field data collections, demonstrations, performance evaluation, and risk analysis. Partly on the basis of the results ofthis program, the FAA recently authorized independently sequenced approaches to parallel runways separated by 3400 feet or more, when these approaches are monitored with a PRM system. The FAA also initiated an implementation program to install PRM systems at several major U.S. airports. This article reports the results offield activities carried out by Lincoln Laboratory; the use ofthese results to verifY the performance and safety of the PRM system, and continuing development that is part ofthe Lincoln Laboratory PRM program.