"The Hump" was the nickname for one of the most hazardous air transport routes of World War II: from India to China, over the Himalayas. Because the Japanese Empire had taken over most of eastern China at the time, the only way to keep the Kuomintang supplied with gasoline, firearms, medicine, and other necessities was to ferry them by air over Tibet and Bhutan.

The Hump route was inaugurated in 1942 at the time of the Doolittle raid on Tokyo, in an effort to supply emergency bases for Allied bombers in the Pacific. After the Doolittle mission, the Air Transport Command took over the Hump and began ferrying supplies in C-46, C-47, and C-87 aircraft. By the end of the war, the Hump was bringing 70,000 tons of supplies into China each month.

800 pilots died flying the Hump: the ground below them was often higher than the recommended cruising altitude of their aircraft. Many of the aerodromes in India and China were poorly equipped and remotely located. At some airfields, pilots would have to take off at night by aiming toward a pair of headlights at the other end of the runway. Stories abound of pilots who crashed in Tibet and were brought home in heavy hand-hewn bamboo coffins built by local villagers.

The Hump was first used by China National Aviation Corporation, which later became a division of Pan American Airways. The Flying Tigers also used the Hump to get to and from China.