KC-33A
A proposed 747 was also adapted as an aerial refueling tanker and was bid against the DC-10-30 during the 1970s Advanced Cargo Transport Aircraft (ACTA) program that produced the KC-10A Extender.
This aircraft is based upon existing Boeing 747 aircraft and combines midair refueling capabilities with a reinforced upper deck that can carry vehicles, particularly light armor, such as the M113A3. A fold-out ramp would be carried in the nose of the aircraft to allow vehicles to drive on and off of the aircraft. Under the deck would be a set of tanks and pumps to allow the aircraft to refuel other aircraft or simply engage in very long-range missions.
