The increase in thrust obtainable from a power plant installation using the cooling-air as a propulsive jet

Abstract

The net thrust or drag of a power-plant cooling system has been estimated for various flight speeds. The effect of using the exhaust heat inside the duct is considered, and also the effect of burning additional fuel behind the engine. Typical figures are taken to produce a set of curves, from which the respective merits of the various systems considered can be assessed in a general manner. It is concluded that useful gains in total thrust might be obtained at top speed by the use of internally discharging exhausts. The gain from auxiliary fuel burners behind the engine would only be considerable at very high speeds.