A Phased Approach to Increase Airport Capacity through Safe Reduction of Existing Wake Turbulence Constraints

Abstract

Previous wake turbulence research has suggested that using knowledge of wake turbulence behavior to develop candidate arrival and departure procedures would increase capacity at a variety of United States airports. This paper outlines the operational issues involved as well as the process through which the Federal Aviation Administration (FAA) and The MITRE Corporation’s Center for Advanced Aviation System Development (MITRE/CAASD) analyzed an evolving set of candidate procedures. This work is part of the broader effort to implement an FAA/National Aeronautics and Space Administration (NASA) Wake Turbulence Research Management Plan (RMP).We describe in detail two candidate procedures, their operational variations and the expected capacity benefits at selected airports. The first procedure is a near-term proposed change to the 2500 foot runway centerline separation minimum for dependent approaches to two Closely Spaced Parallel Runways (CSPR). When visual separation can not be provided, the current FAA rule requires parallel runways spaced less than 2500 ft to be treated as a single runway. While in-trail wake separation standards are dependent on wake categories of the generating and encountering aircraft, this rule is not. This paper shows that, by refining this standard to reflect the wake generation differences of different weight classes, substantial capacity benefits may be possible. Variations on this procedure are analyzed to explore the sensitivity of the capacity benefits to the underlying assumptions.The second procedure is a mid-term proposed change to reduce wake constraints for departures from parallel runways spaced closer than 2500 ft using a short-term prognosis of crosswinds at and near the area of aircraft rotation. A brief outline is provided of activities planned during 2004 to advance towards the specific design and implementation of these procedures. Once such activity is additional wake data collection at St. Louis (STL).