THIS paper deals in a general way with a brief history of the work that has been done in the past on aircraft fuel systems to adapt them for high-altitude flight, the reasons for failures that developed, some of the physical aspects of aircraft fuel at high altitude, and a brief description of the Thompson Booster system.
The discussion of the physical behavior of aviation fuel at high altitude is based upon observations made during many laboratory tests. Observed behavior of fuel systems in laboratory altitude simulations is described and differences between this and apparent behavior during actual flight are explained. Due to these differences, it is pointed out, no direct correlation between laboratory simulations and actual flight performance can be made at the present time. Until this handicap can be overcome, prediction of fuel-system performances must be based upon comparison between simulation tests some of which are simulations of satisfactory fuel systems.
The Thompson Booster system was evolved as the result of the application of analytical reasoning to the fuel systems that preceded it. The booster unit is a modified centrifugal pump, attached directly to the fuel tank and driven by an electric motor. Its function is to prevent entrance of released vapor and air to the fuel line leading to the fuel pump on the engine. It also maintains sufficient pressure in this line to prevent additional release of air or vapor.
