The AJ Savage was the first U.S. bomber designed especially to carry the atomic bomb. It was North American's first attack bomber for the U.S. Navy and was designed shortly after the end of World War II. It was a large twin-engine Heavy Attack aircraft for the Navy. In those early years of jet aircraft development, manufacturers were exploring ways to provide power using piston engines and a jet engine on the same airframe. The AJ-1 attack bomber used two 2,400 horsepower piston engines to power four-bladed propellers for long-range cruise. It then fired a 4,600-pound-thrust turbojet engine for extra speed over the target.