Accession Number:

AD0258780

Title:

PERFORMANCE THEORY FOR HIGH SPEED GROUND EFFECT MACHINES

Descriptive Note:

Corporate Author:

VEHICLE RESEARCH CORP PASADENA CALIF

Personal Author(s):

Report Date:

1961-06-01

Pagination or Media Count:

1.0

Abstract:

The cruise flight of vehicles of rectangular planform employing an air pressure seal between the ground and the vehicle along the two streamwise sides is considered. The variation of the optimum rearward deflection angle of the side jet pressure seal with speed for minimum over-all power expenditure and maximum range is found. It is concluded that a mixed propulsion system jet deflection plus propellers is required. Volume flow and the corresponding fan pressure rise needed are also calculated. The maximum liftdrag ratio is determined. The maximum thickness ratios of the vehicles are considered to be large compared to the ground heightvehicle length ratio. Two-dimensional airfoil theory is employed to show that close to stagnation conditions exist below the vehicles. The lower surface lift, pitching moment, and aerodynamic center location are determined. The flow over the upper surface is identified with flow over mounds. Upper surface lift coefficients are determined for typical mound shapes. High total lift coefficients are theoretically obtainable with almost zero induced drag. The conventional induced drag power penalty is replaced by a sealing air power expenditure. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE