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Smith, H. C.

Publications and source records attributed to Smith, H. C..

Study of winglets applied to biplanes

The possibility of improving the aerodynamic characteristics of a biplane configuration by adding winglets is examined both theoretically and experimentally. Theoretical calculations show good agreement with experiment in predicting inviscid drag due to lift. Theoretical and experimental results indicate that the addition of winglets to an optimized biplane configuration can increase the ideal efficiency factor by up to 13 percent, as well as increasing the lift curve slope and maximum lift coefficient.

Gall, P. D.↗

Study of winglets applied to biplanes

This paper examines, both theoretically and experimentally, the possibility of improving the aerodynamic characteristics of a biplane configuration by adding winglets. Theoretical calculations show good agreement with experiment in predicting inviscid drag due to lift. Theoretical and experimental results indicate that the addition of winglets to an optimized biplane configuration can increase the ideal efficiency factor by up to 13 percent, as well as increasing the lift-curve slope and maximum lift coefficient. A theoretical analysis comparing the biplane with an optimized winglet to an equivalent monoplane indicates that the biplane has the potential for a 6.4-percent increase in L/D(max), and 13-percent increase in C(L) to the 3/2-power/C(D), the classical endurance parameter.

Gall, P. D.↗

Myocardial blood flow: Roentgen videodensitometry techniques

The current status of roentgen videodensitometric techniques that provide an objective assessment of blood flow at selected sites within the coronary circulation were described. Roentgen videodensitometry employs conventional radiopaque indicators, radiological equipment and coronary angiographic techniques. Roentgen videodensitometry techniques developed in the laboratory during the past nine years, and for the past three years were applied to analysis of angiograms in the clinical cardiac catheterization laboratory.

Smith, H. C.↗

Effect of the six engine air breathing propulsion system on space shuttle orbiter subsonic and transonic stability and control characteristics (OA91)

Experimental aerodynamic investigations were conducted on a 0.015 scale representation (Model 42-0) of the VL70-000139B space shuttle orbiter configuration. The test objective was to determine the effect of three air breathing propulsion system ferry/flight test configurations on the transonic drag rise, the elevon effectiveness, the longitudinal stability, and the lateral-directional stability of the -139B shuttle orbiter. The model was sting mounted on a Task 1.5 inch internal strain gage balance, and six-component aerodynamic force and moment data were recorded over an angle of attack range of minus 3 deg to 14 deg at Mach numbers of 0.5, 0.6, 0.7, 0.8, and 0.9 with a Reynolds number of 6.4 million/ft. Data were also recorded at a sides lip angle of five degrees.

Smith, H. C.↗