The McDonnell Douglas F-15 Eagle is an American twin-engine fighter and attack aircraft, the first flight of which took place on July 27, 1972. The F-15 aircraft is the result of the experience gained from air combat over Vietnam, and is also the USAAF's response to the Soviet Mig-23 and Mig-25 fighters. It was created as part of the FX (Fighter Experimental) project, in which the winner was McDonnell-Douglas in 1969. When designing the F-15, particular emphasis was placed on reducing service time as much as possible. It mainly consisted, on the one hand, in assembling elements that were as easy to use as possible, and, on the other hand, in the use of automatic systems, which were kind of saving people. As a result, the successor of the F-4 Phantom, surpassing it in all respects, can be served in half the time.