Lockheed C-5 Galaxy is a large American military cargo plane manufactured by Lockheed. It has been in service since 1968. It gave its first service in the Vietnam War and carried a quarter million tons in the 2nd Gulf War. Its value is $300 million. It requires weekly maintenance for every hour it spends in the air, and it is the US Army's largest cargo plane ever built. The landing gear is designed to be folded in and has the ability to take off in 20 seconds or less. If the center of gravity of the loaded load changes due to the weight of the aircraft, the aircraft may remain suspended in the air and fall quickly to the ground, causing major casualties. Therefore, these studies are carried out with great care while loading the load.

The development of the C-5 Galaxy was complex, including significant cost overruns, and Lockheed faced significant financial difficulties. Shortly after entering service, cracks were discovered in the wings of many aircraft, and the capacity of the C-5 squadron was limited until remediation was completed. The C-5M Super Galaxy is an upgraded version with new engines and modernized avionics designed to extend life beyond 2040.

The USAF has operated the C-5 since 1969, at that time the transport aircraft supported military operations in all major conflicts, including the United States, Vietnam, Iraq, Yugoslavia, and Afghanistan, as well as allied support, as with Israel during operations in the Yom Kippur War and the Gulf War. The galaxy has also distributed humanitarian aid, provided disaster relief, and supported the US space program.