Accession Number : AD0736925

Title :   A New Approach to the Calculation of the Effect of the Ground on the Performance of Rotary Wing Aircraft,

Descriptive Note : Special project rept.,

Corporate Author : NAVAL AIR SYSTEMS COMMAND WASHINGTON D C PROFESSIONAL DEVELOPMENT CENTER

Personal Author(s) : Newman,Eugene M.

Report Date : 01 NOV 1971

Pagination or Media Count : 26

Abstract : An investigation of the helicopter ground effect prediction methodology was made and evaluated. Prediction of IGE performance for single rotor helicopters of a conventional type at z/D's greater than .4 can be attained with a resonable degree of accuracy through the use of empirical curves which consider rotor geometry only. Improved accuracy can be attained by use of the new method developed for this investigation which gives results that reflect changes in fuselage shape as well as rotor geometry. While insufficient data was available, the new method appears to provide a means of predicting ground effect for compound type vehicle that entail significant configuration changes. (Author)

Descriptors :   (*HELICOPTERS, *GROUND EFFECT), PREDICTIONS, ACCURACY, ROTARY WINGS, PERFORMANCE(ENGINEERING), DOWNWASH

Subject Categories : Aerodynamics
      Helicopters
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE