The A-10 Thunderbolt II is a single-seat, twin-engine jet aircraft built to provide close environment assistance (CAS) of ground forces by attacking tanks, armored automobiles, along side ground goals. As another goal, it provides airborne forward atmosphere control, leading other aircraft against ground goals. It's the very first United States Air Force aircraft created solely for CAS. A -10A : Single-seat close environment help,ground-attack variation.