North American P-51 Mustang Originally designed for the British, who requested North American build the Curtiss P-40 under license. North American led by James Kindelberger , suggested a more modern fighter and as quick as tooling up for the old outdated P-40. From design to flying prototype was accomplished in an amazing 102 days. Today the debate goes on as to whether the P-51 Mustang was the best fighter in WWII, generally the consensus going to the Mustang. It served very well around the world but lacked high altitude performance. The introduction of the Rolls Royce Merlin engine with it’s two stage super charger, it was superior to any other fighter in the world except for turn radius. After WWII the Mustang remained in service with the Air National Guard here at home and became the front line fighter for most countries around the world. Today they are highly prized by wealthy business people (2 to 5 million US dollars) and favorite air racing plane. Voodoo currently holds the world speed record of over 500mph.