The U.S. Air Force is always working on its next generation of aircraft. At the moment, many air force generals are talking about an unmanned heavy bomber. For several years now, the air force has been tossing around ideas on what the next generation heavy bomber should be. In the half last century, the air force has developed six heavy bombers (the 240 ton B-52 in 1955, the 74 ton B-58 in 1960, the 47 ton FB-111 in 1969, the 260 ton B-70 in the 1960s, the 236 ton B-1 in 1985, and the 181 ton B-2 in 1992.) All of these were developed primarily to deliver nuclear weapons (bombs or missiles), but have proved more useful dropping non-nuclear bombs. Only the B-70 was cancelled before being deployed. The B-1 was delayed and almost cancelled, but proved that the air force would do anything to keep the heavy bombers coming. The air force generals are now asking the aircraft designers for a supersonic, long range heavy bomber that could operate with, or without, a crew. Since the B-2 requires only a two pilots, and many commercial airliners have flight control equipment that, with a little tweaking, could eliminate the pilots altogether, the idea of heavy bomber UAV is well within the capabilities of current technology. The way this is going, it's likely that the next heavy bomber will be big, fast, stealthy and uninhabited.