CASE STUDY

Close-In Parallel Runway Analyses - Nationwide

Client
Federal Aviation Administration

Under current FAA air traffic control guidelines, parallel runways must be separated by a minimum of 4,300 feet in order to serve independent, parallel Instrument Flight Rule (IFR) arrival streams. 

Through the use of new generation rapid update airport surveillance radars, the FAA has promulgated rules which allow runways separated by as little as 3,400 ft to conduct simultaneous IFR arrival streams.  With E-scan radars, that separation may potentially be as low as 2,500 ft.

In order for these “Close-in” runways to accommodate parallel independent IFR arrivals, a series of minimum requirements are needed at the facility (FAA Order 8260.41, 9/15/95).  One of those requirements is a clear Parallel Approach Obstruction Assessment Surface (PAOAS), which is a surface designed to protect aircraft that may be diverted by air traffic control while on approach and leaving the TERPs area.  This PAOAS surface is a highly restrictive surface and requires extensive evaluation to determine what obstacles, if any, are obstructing the surfaces.

GCR is part of the FAA team which evaluates each airport which is a candidate for a close-in parallel approach.  In this capacity, GCR’s primary responsibility is to evaluate and assess the condition of the PAOAS surface and determine is obstructions are present.  To date, eight airports have been assessed by the GCR team, as follows:

• William B. Hartsfield-Atlanta International
• Indianapolis International
• Minneapolis-St. Paul International
• St. Louis international-Lambert Field
• Raleigh-Durham International
• John F. Kennedy International
• Philadelphia International
• Memphis International