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Experimental investigations have been conducted to evaluate the aerodynamic performance and control of Unlimited-class hydroplanes racing at speeds exceeding 200 mph. These vehicles operate in very strong ground effect and may encounter unexpected disturbances such as wind gusts or waves, which can cause uncontrolled pitch-up and destruction. Specific test techniques have been developed in a modified subsonic wind tunnel to simulate these conditions, allow evaluation of the vehicle's aerodynamics and develop novel control surfaces. The paper presents details of these facilities and test techniques, associated wing-in-ground-effect tests, and characteristics of the pitching hydroplane as it transitions between in- and out-of-ground effect.

The recycling and reclamation of metal-matrix composites (MMC's) are critical aspects of the commercialization process. By recycling, we mean the economic processing of MMC scrap for reuse as composite. Reclamation refers to the separation and recovery of the individual components of the composite, i.e., the various aluminum alloys and ceramic particles. Three forms of MMC wrought alloy scrap have been considered; i.e., D. C. (direct chill) cast log ends, extrusion butts, and cut extrusion scrap. Recycling each of these forms of scrap back into D. C. cast extrusion billet has been demonstrated. This has been accomplished by recycling the scrap back through the basic mixing process. Various ratios of scrap to virgin composite have been explored and optimum blends are being studied. Similarly, for MMC foundry alloy (high silicon) gates and risers produced in shape-casting, fluxing and degassing techniques have been developed so these may be recycled back into useful castings.