I started messing with Wiki and typing in big airplanes and this airplane showed up. it was the B-36 peacemaker and in its time it was the 1950's version of the B-2 bomber in terms of cost.
[N 1] was a strategic bomber built by Convair and operated solely by the United States Air Force (USAF) from 1949 to 1959. The B-36 was the largest mass-produced piston engine aircraft ever made. It had the longest wingspan of any combat aircraft ever built (230 ft or 70 m), although there have been larger military transports. The B-36 was the first bomber capable of delivering any of the nuclear weapons in the US arsenal from inside its two bomb bays without aircraft modifications. With a range greater than 6,000 mi (9,700 km) and a maximum payload of 72,000 lb (33,000 kg), (and thereby having the ability to carry both the United States' atomic fission and fusion weapons), the B-36 was the world's first manned bomber with an unrefueled intercontinental range.
More at this linkhttp://en.wikipedia.org/wiki/Convair_B-36