Analysis of Predicted Aircraft Wake Vortex Transport and Comparison with Experiment Volume II -- Appendixes

PDFTech ReportDOT-TSC-FAA-74-07-2FAA-RD-74-74-2DOT-TSC-593WakesVorticesWind shearTurbulenceUnited States. Federal Aviation AdministrationBrashears, M. R.Logan, N. A.Robertson, S. J.Shrider, K. R.Walters, C. D.John A. Volpe National Transportation Systems Center (U.S.)Lockheed MartinNTL-AVIATION-AVIATIONNTL-AVIATION-Aviation Energy and EnvironmentVolpe National Transportation Systems Center, Technical Reference CenterA unifying wake vortex transport model is developed and applied to a wake vortex predictive system concept. The fundamentals of vortex motion underlying the predictive model are discussed including vortex decay, bursting and instability phenomena. A parametric and sensitivity analysis is presented to establish baseline uncertainties in the algorithm to allow meaningful comparison of predicted and measured vortex tracks. A detailed comparison of predicted vortex tracks with photographic and groundwind vortex data is presented. Excellent agreement between prediction and measurement is shown to exist when sufficient wind data are available. Application of the Pasquill class criteria is shown to be an effective technique to describe the wind profile in the absence of detailed wind data. The effects of wind shear and the Ekman spiral on vortex transport are discussed. It is shown that the combination of wind shear and ground plane may be possible mechanisms underlying vortex tilting and a theoretical explanation is advanced that is somewhat supported by comparison with the experimental data. Finally, recommendations for further vortex data collection in the vicinity of an airport are presented