A summary of government sponsored research work now in progress is presented in tabular form and by task description. This information is confined to the Appendices however, and the main part of the paper consists of a short design study for an Amphibious Support GEM. Thoughts are presented on how best to achieve optimum performance once the military requirements for such a vehicle are developed. Considerations of the various trade-offs and compromises that might be necessary are pointed out; final design figures are presented along with the performance and design parameters used so that anyone wishing will be able to follow through on the derivations. From the study the following conclusions are reached:
  1. 1.
    Reasonable GEM's in the 60,000 pound gross weight class will have optimum speeds approaching 100 knots.
  2. 2.
    High speed GEM's will have either variable width peripheral nozzles or variable vanes in the peripheral nozzles.
  3. 3.
    A method for adjusting the ratio of cushion to propulsion power must be provided.
  4. 4.
    The degradation in performance of GEM's of the sizes considered with increase in gross weight is not as large as had been thought.
All of these conclusions are quite significant to the potential application of GEM's in the Amphibious Support field where high speed, high payload and the truly amphibious vehicle have eluded us for so long.


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