Accession Number:

AD0878776

Title:

Low Altitude Atmospheric Turbulence LO-LOCAT Phase 3. Volume 1, Part 1, Data Analysis.

Descriptive Note:

Final technical rept. 17 Apr 1968-17 Aug 1970

Corporate Author:

BOEING WICHITA CO KS

Report Date:

1970-10-01

Pagination or Media Count:

456.0

Abstract:

The report presents procedures, analysis methods, and final results pertaining to the LO-LOCAT Phase 3 program. Approximately 150 hours of low altitude 100 - 1000 feet turbulence and associated meteorological data were recorded from 16 August 1968 through 30 June 1969. A model of the turbulence environment at low-level is presented in terms of gust velocity primary peaks, level crossings, amplitude samples, rms values, and gust maxima, as well as derived equivalent gusts, turbulence scale lengths, and power spectra. Mathematical expressions for turbulence spectra, scale length, and primary peak statistics are shown. Correlations between atmospheric gust velocities and meteorological and geophysical phenomena are evaluated. It was found that gust velocity magnitude at low altitude is most affected by atmospheric stability and terrain. Gust velocity rms values above 1.5 fps may be approximated by truncated Gaussian distributions. For wavelengths less than 15,000 feet, turbulence spectra are best represented by the von Karman mathematical expressions. The turbulence, sampled for 4-12 minute intervals over a distance of approximately 32 miles at absolute altitudes below 1,000 feet, was found to be basically stationary, isotropic, and homogeneous

Subject Categories:

  • Atmospheric Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE