It belongs to the fifth generation, whose main advantage lies in concealment from radar screens. It is produced through a joint project between Lockheed Martin and Boeing. The first flight was in 1997. It entered service in December 2005. The plane uses “Pratt & Whitney F119” engines. This plane was produced For the US Army only and not operated by any other air force in the world. Nearly 180 fighters were produced between the years 1996 and 2011. The cost of each aircraft is $143 million. Congress refused to fund any increase in production due to its high cost. The aircraft has a high ability to maneuver in the air with Additional features related to ground attack and electronic warfare. Its operational cost is about $44,000 per flight hour. It requires 30 hours of maintenance for the hydraulic and mechanical equipment after the flight, despite the ease of maintaining its engine. Its maximum speed is Mach 2.25 (2.4 thousand km/h).