Using real-time aircraft reports of wind and environmental parameters to enable dynamic cockpit-based wake tools

Abstract

The Federal Aviation Administration (FAA) is implementing the Next Generation Air Transportation System (NextGen) in the U.S. National Airspace System (NAS). The MITRE Corporation's Center for Advanced Aviation System Development (MITRE/CAASD) is supporting the FAA in this mission, and conducts research activities that assist the FAA in leveraging emerging aircraft capabilities. A key area of research is evaluating the feasibility of delegating longitudinal (i.e., in-trail) aircraft spacing to pilots even during low visibility conditions. Longitudinal spacing is needed for avoiding collisions but also for wake turbulence avoidance. As longitudinal spacing is delegated to the flight crew, flight deck-based wake tools are needed to support the task. The pilots need to increase their situational awareness not only of the nearby aircraft but of the wakes that these aircraft produce. The current spacing provided by controllers is dictated by conservative assumptions regarding wake turbulence propagation. Wake turbulence is influenced by the characteristics of the aircraft that produced it as well as winds and other atmospheric conditions. This information could conceivably be transmitted by each aircraft as it enters various phases of flight, such as the approach to an airport. A trailing aircraft could then use this information to construct a picture of the probable location of the wake which would increase the pilot's situational awareness of the wake. To make a realistic assessment of the location and strength of a wake vortex, real-time weather information needs to be known in the vicinity of the aircraft producing the wake. This paper addresses the quality of that information and how any uncertainty in this information will affect the estimate of the location and strength of wake using current wake dynamics estimating programs that could be used on an aircraft. There are systems currently on aircraft that transmit precisely this information to the ground. In the United States there are several airlines that participate in the Meteorological Data Collection and Reporting System (MDCRS) run by ARINC for the airlines. This data has been archived by the National Oceanic and Atmospheric Administration (NOAA) since 2001. Using this data, we have found that there is uncertainty in wind and other atmospheric parameters, even in the approach phase of flight, over a short span of time. Using these results, we show the uncertainty in the wake positions and discuss the implications for using this information for cockpit visualization tools.