1.3
(The FAA's Wake Turbulence Research Program)

When weather forces marginal VMC or IMC operations, many airports currently experience congestion, which impacts safety and causes costly delays. Improvements in navigation and surveillance technologies and procedures can safely provide the needed efficiency gains, provided that constraints due to wake turbulence can be accommodated. Project SOCRATES is the current FAA program for developing the wake turbulence safety net and standards required for application of the new technologies. The initial focus is on capacity issues and safety at airports with closely spaced parallel runways. Airports with closely spaced parallel runways routinely use both runways for VMC operations. In IMC, closely spaced runways less than 2500 feet apart are operated as a single runway due to wake turbulence constraints. This severely reduces capacity and frequently causes extensive delays, which may extend throughout the system. For example, United Airlines has stated that delays at San Francisco cost $100 million per year.

There is general agreement that new runways with greater separation are the most effective solution to the capacity problem. However, this may not be feasible due to airport space, cost, or environmental constraints. Current research initiatives to allow better utilization of closely spaced runways in IMC include SOIA (Simultaneous Offset Instrument Approach), ATS (Along Track Separation), paired approaches using ADS-B technology, and NASA's AILS (Airborne Information for Lateral Spacing) Program. Implementation of any of these technologies for runways less than 2500 feet apart requires a reassessment of current wake turbulence constraints. The initial focus of Project SOCRATES is to define appropriate wake turbulence constraints and thus enable the implementation of safer and more efficient technologies and procedures. A wake monitoring system has been installed at SFO to gather data required to validate models of wake motion and decay characteristics. The wake models and data will be used to propose operational wake turbulence standards. The research is integrated with NASA's AVOSS wake avoidance technology.