Phase A Interim Report

The contents of this report describe accomplishments during the first half of the Low-Level Critical Air Turbulence (LO-LOCAT) Phase III program. Data that were obtained during flight over routes near McConnell Air Force Base, Kansas, and Edwards Air Force Base, California, are presented. Also included are time histories of some of the larger magnitude gust velocities recorded over the Peterson Field, Colorado route. Approximately 72 hours of low-level (0-1000 feet) turbulence and associated meteorological data recorded from August 16, 1968, through January 8, 1969, are presented. The turbulence environment is analyzed in terms of gust velocity primary peaks, amplitude samples, rms values, maximum values and derived equivalent gusts. Mathematical expressions for turbulence spectra and scale length statistics, and correlations between atmospheric gust velocities and meteorological and geophysical phenomena are shown. The most predominant characteristics of these data are the increases in rms values, scale lengths, Taylor micro scales and maximum gust values as compared to the LO-LOCAT Phases I and II data. These differences are attributed to the increased speed of the Phase III airplane which is providing a better definition of the longer wavelengths of atmospheric turbulence. This report consists of two volumes. Volume I contains a discussion of data acquisition and quality, along with a preliminary analysis of turbulence and meteorological data.