A PERFORMANCE EVALUATION OF PROPULSION SYSTEM CONCEPTS FOR A SMALL DIRECT SUPPORT FIGHTER

A design evaluation is presented for four different propulsion system approaches for a Direct Support Fighter in the 15,000 to 20,000 pound class. This includes three different arrangements for composite lift engine and main propulsion arrangements and one lift fan and wing arrangement. For a given payload range the factors considered are take-off weight, performance under single engine failure conditions, STOL performance, and cost. The results indicate that vectoring the cruise engine for lift is not necessarily optimum. V/STOL vehicles can be designed to sustain altitude after a single engine failure, for a small weight penalty. Reducing the number of lift engines has an insignificant effect on overall weapon system cost.