Under a study called ACMA, for Advanced Commercial/Military Aircraft, a transport aircraft design that was about twenty percent larger than a C-5 Galaxy was developed
If one very large cargo aircraft could move a lot of cargo at one time, two could move even more, right?
That was the basic premise of this conceptual design looked in the early 1980s by engineers at the then-Lockheed-Georgia Company in Marietta, Georgia. Under a study called ACMA, for Advanced Commercial/Military Aircraft, a transport aircraft design that was about twenty percent larger than a C-5 Galaxy was developed. According Code One Magazine, the multibody transport shown here used the basic ACMA design with a joined wing and six engines. Note that only the left fuselage has a flight deck. While this design could literally carry tons and tons of cargo, finding enough runways wide enough to support it was an obvious drawback.
By contrast the C-5 is able to operate on runways 6,000 feet long (1,829 meters), quite an impressive (especially for its size) capability.
The C-5 has a greater capacity than any other U.S. Air Force (USAF) airlifter. It has the ability to carry 36 standard pallets and 81 troops simultaneously. The Galaxy is also capable of carrying any of the Army‘s air-transportable combat equipment, including such bulky items as the 74-ton mobile scissors bridge. Ground crews are able to load and off-load the C-5 simultaneously at the front and rear cargo openings, reducing cargo transfer times. Other features of the C-5 are:
– Five sets of landing gear totaling 28 wheels to distribute weight
– Nose and aft doors that open the full width and height of the cargo compartment to permit faster and easier loading
– A “kneeling” landing gear system that permits lowering the parked aircraft to facilitate drive-on/drive-off vehicle loading and adjusts the cargo floor to standard truck-bed height
– Full-width drive-on ramps at each end for loading double rows of vehicles
– A maintenance diagnostics system that records and analyzes data from more than 800 (C-5A) and 7000 (C-5M) test points, reducing maintenance/repair time.

Photo credit: Lockheed Martin
Artwork courtesy of AircraftProfilePrints.com