P-38 TURBO-SUP ERCHARGER

摘要

Even in the Great War, air combat moved to ever greater heights as pilots sought to gain the advantage. Engine performance - and the pilot's capability - was compromised by diminishing air density, and thus the lack of oxygen, as altitude increased. At 18,000ft, for example, air pressure is half that at sea level. The advantage of reduced aerodynamic drag at altitude is more than offset by the reduction in engine performance due to the ram-air into the carburettor having only half-combustible (oxygen) content. As well as reduced power, this results in unburnt fuel being ejected, and problems with engine running. By the 1930s, engineers were finding ways to regain piston engine performance at altitude. Two main options were developed: supercharging and turbo-supercharging, or turbocharging.