Lockheed Flatbed

The Lockheed Flatbed was a proposed cargo aircraft design from the 1980s that carried large loads in the open on the back of the aircraft, much like a flatbed truck, and its name was unofficial because no formal name was ever assigned. Conventional cargo aircraft usually fill their hold by mass before they fill it by volume and so fly mostly empty inside while carrying a large fuselage for rare bulky loads. Lockheed's concept used an airliner-sized fuselage for the common case and, for an oversized load, removed the cargo bay and chained the load directly to the open back. The aircraft sat low so trucks could push loads onto the bed, which used parallel I-beams with metal sheeting on top and raised rollers for pallets. Because the load rode on top, the wing was low-mounted and the engines sat above it on pylons. Despite public information in the early 1980s, the Air Force never took it up and it disappeared by the mid-1980s.