Super Guppy Oversize Cargo Transport The transportation of oversized cargo has always been a tremendous problem for logistics planners in government and private industry. The physical limitations of railroad tunnels, narrow roads, low bridges, and power lines make overland shipment of such cargo extremely problematic, if not impossible. NASA's Super Guppy offers a practical and economical solution to these problems. Although there are other aircraft capable of carrying more weight than the Super Guppy, very few come close to its internal dimensions. Boasting an immense cargo area that is 25 feet in diameter and 111 feet long, the Super Guppy can carry items that are virtually impossible to fit inside other cargo aircraft.