Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

The primary objective of this thesis is to correlate computed theoretical data with experimentla data for wings in ground effect. This investigation uses the PANAIR computer program--a higher-order panel method to predict the lift and drag characteristics of an aspect ratio two wing, with and without endplates, operating at low speed in ground effect. The effects of altitude, trailing edge flap deflection and angle of attack are considered. Numerical results are compared with subsonic wind tunnel experimental data. For both the numerical and experimental methods, the image model technique is used to simulate ground effect. Excellent agreement between numerical results and experimental data is achieved for the wing without endplates down to low (approximately 10% of wing chord) altitudes. For the wing with endplates, numerical results are in good agreement with experimental data for altitudes greater than approximately 20% of the wing chord. PANAIR results diverged from experimental data at lower altitudes because the model did not attempt to account for spanwise flow between the bottom of the endplate and the ground, and other viscous effects which tend to become dominant. These include a static pressure increase beneath the wing and wake distortions behind the configuration. Keywords include: Aspect ratio, WIG(Wing in Ground Effect), Life coefficients, Life drag ratio, and Inviscid theory.

A wind-tunnel investigation has been conducted to determine the effect of ground proximity on the aerodynamic characteristics of thick highly cambered rectangular wings with aspect ratios of 1, 2, 4, and 6. The results showed that, for these aspect ratios, as the ground was approached all wings experienced increases in lift-curve slope and reductions in induced drag which resulted in increases in lift-drag ratio. Although an increase in lift-curve slope was obtained for all aspect ratios as the ground was approached, the lift coefficient at an angle of attack of 0 degrees for any given aspect ratio remained nearly constant. The experimental results were in general agreement with Wieselsberger's ground-effect theory. As the wings approached the ground, there was an increase in static longitudinal stability at positive angles of attack. When operating in ground effect, all the wings had stability of height at positive angles of attack and instability of height at negative angles of attack. Wing-tip fairings on the wings with aspect ratios of 1 and 2 produced small increases in lift-drag ratio in ground effect. (Author).