The Fairchild-Republic A-10A Thunderbolt II is the only Western fixed-wing aircraft which has been designed without compromise for the close air support (CAS) mission (the Russian Su-25 “Frogfoot� shares a similar design philosophy). All of its unique characteristics originate from CAS requirements, including low speed, long endurance, extensive armor, and heavy built- in armament. However, its dedication to the unglamorous CAS mission has also been the reason why it has been largely overshadowed by its supersonic contemporaries.