CONVECTIVELY INDUCED TURBULENCE ENCOUNTERED DURING NASA’S FALL-2000 FLIGHT EXPERIMENTS.pdf

CONVECTIVELY INDUCED TURBULENCE ENCOUNTERED DURING NASA’S FALL-2000 FLIGHT EXPERIMENTS David W. Hamilton and Fred H. Proctor NASA Langley Research Center Hampton Virginia 23681-2199 Paper: 10.8, pages 371-374 Preprints of 10 th Conference on Aviation, Range and Aerospace Meteorology 13-16 May 2002, Portland Oregon American Meteorology Society 371 CONVECTIVELY INDUCED TURBULENCE ENCOUNTERED DURING NASA’S FALL-2000 FLIGHT EXPERIMENTS David W. Hamilton and Fred H. Proctor NASA Langley Research Center, Hampton, Virginia 1. INTRODUCTION Aircraft encounters with atmospheric turbulence are a leading cause of in-flight injuries aboard commercial airliners and cost the airlines millions of dollars each year. Most of these injuries are due to encounters with turbulence in and around convection. In a recent study of 44 turbulence accident reports between 1990 and 1996, 82% of the cases were found to be near or within convective activity (Kaplan et al. 1999). According to NTSB accident reports, pilots’ descriptions of these turbulence encounters include “abrupt”, “in Instrument Meteorological Conditions (IMC)”, “saw nothing on the weather radar”, and “the encounter occurred while deviating around” convective activity. Though the FAA has provided guidelines for aircraft operating in convective environments, turbulence detection capability could decrease the number of injuries by alerting pilots of a potential encounter. The National Aeronautics and Space Administration, through its Aviation Safety Program, is addressing turbulence hazards through research, flight experiments, and data analysis. Primary focus of this program element is the characterization of turbulence and its environment, as well as the development and testing of hazard- estimation algorithms for both radar and in situ detection. The ultimate goal is to operationally test sensors that will provide ample warning prior to hazardous turbulence encounters. In order to collect data for support of these activities, N