The B-29 was also the world’s heaviest production plane because of increases in range, bomb load and defensive requirements. The tail gunner had a separate pressurized area that could only be entered or left at altitudes that did not require pressurization. Two crew areas, fore and aft, were pressurized and connected by a long tube over the bomb bays, allowing crew members to crawl between them. One of the most technologically advanced airplanes of World War II, the B-29 had many new features, including guns that could be fired by remote control.
Boeing submitted the proposal for the B-29 long-range heavy bomber to the Army in 1940, before the United States entered World War II.
