The P51 Mustang was one of the most effective fighters of WWII. The first flight of the P51 Mustang was in September 1942. The aerodynamics of the Mustang were excellent but initially it was underpowered. Originally fitted with an Allison engine, it was later fitted with a powerful V-1650 Merlin engine, producing 1,695 horsepower. The P51 B was first used in December 1943 and in May 1944, the P51-D was introduced. The Mustang's maximum speed was 437 mph (490 mph for the P51H), with a cruising speed of 275 mph. The Mustang had a range of 1,000 miles that increased to 1,300 miles for those aircraft equipped with fuel drop tanks.
The P51 Mustang had an astonishing success rate. Its ratio for kills to losses was said to have been 19 kills for every 1 Mustang lost. The P51 Mustang is credited with the destruction of 4,950 German planes ? more than any other Allied fighter. Such was the success of the Mustang, that the Senate War Investigating Committee set up by Harry Truman in 1944, called it ?the most aerodynamically perfect pursuit plane in existence.?