Use of Aircraft-Based Data to Evaluate Factors in Pilot Decision Making in Enroute Airspace

In the summer of 2008, Lincoln Laboratory and Rockwell Collins conducted four flight missions (three on 17 July and one on 14 August) in the instrumented Rockwell Saberliner Model 50 research aircraft in and around thunderstorms over the northern Great Plains states. The goals of the missions were to gather aircraft data to validate weather avoidance fields (WAF) output from convective weather avoidance models (CWAM), and to provide insights into the cockpit environment and pilot decision making. Aircraft acceleration data, airborne weather radar, and cockpit photographs, video and audio were correlated to ground-based weather radar and WAF fields. The results of an initial analysis that focused primarily on the July flight missions were presented in a previous paper. This paper will extend the initial analysis by examining fields from the radar-based Convective Induced Turbulence (CIT) algorithm, and by analyzing the data gathered from the fourth flight on 14 August, 2008, in greater detail.

The 17 July flight missions were conducted in and around embedded convection while the aircraft was operating in primarily Instrument Meteorological Conditions (IMC). Flight altitudes were restricted to 34,000 ft. or less. The 14 August flight, by contrast, was conducted primarily in Visually Meteorological Conditions (VMC), and a reduced instrumentation payload made possible a flight envelope that included altitudes up to 40,000 ft. The 14 August flight was able to probe areas of convection at multiple flight levels, providing data from different vertical strata of the same storm cells. The nature of the convection encountered during the fourth flight was also significantly different, consisting primarily of isolated or multi-cellular thunderstorms, rather than the more organized, mesoscale systems observed on 17 July.

An analysis of the differences discovered during the fourth flight will be presented comparing and contrasting data from the 17 July mission and the 14 August mission. Data fields from the CIT algorithm will be compared to WAF, onboard weather radar, and aircraft accelerometer data to determine if the CIT fields can be used to improve CWAM performance.

1. DeLaura, Rich, Brad Crowe, Richard Ferris, John F. Love, William N. Chan : “Comparing Convective Weather Avoidance Models and Aircraft-based data”, 89th AMS Annual Meeting Conference on Aviation, Range and Aerospace Meteorology Special Symposium on weather-Air Traffic, American Meteorological Society, Phoenix, AZ, Jan., 2009.