April 1942 - September 1945


USAAF Hump Airlift Operations
April 1942 - September 1945

During World War II the U. S. Army Air Forces (USAAF) established history's first sustained, long distance, 24-hour around-the-clock, all-weather, military aerial supply route. The route extended from the Assam Valley in far northeastern India to the Yunnan province in far southwestern China, a distance of approximately 525 miles. It was made necessary by a United States pledge that it would provide ongoing Lend-Lease war supplies to China to keep it in the war against Japan as an essential part of the overall Allies war effort. This route came to be known as the "Hump Operation". It was located in the China-Burma-India (CBI) theater of operations.

In early 1942 the Imperial Japanese armed forces completed final isolation of China by land and sea when they invaded Burma. This cut off supplies to China moving over the Burma Road, the last remaining land route capable of handling large loads of military supplies in support of China's war against Japan. The only remaining access to China was by air. The only air route available was over far northern Burma.

This aerial route crossed over a generally north-south spur of the Himalaya Mountains, the "Hump". Highest elevations along the route extended from approximately 16,000 feet MSL to the north to approximately 12,000 feet MSL to the far south. The mountain valleys of northern Burma contained dense jungles, occupied by uncivilized native tribes and wild animals. The eastern end of the route fell over the mountainous and plateau area of western China enroute to the main Yunnan province airbase at Kunming. Other satellite airports in the general area of Kunming were also used.

This was a start-from-scratch operation. There was no precedent for it. The route was an area of extremely violent weather, with a wet monsoon weather period occurring from May to October, and heavy thunderstorms, severe aircraft icing and extremely strong winds aloft occurring during the winter months. Navigational facilities were poor and dependable weather reports were scarce. Initially no air traffic control was available, except for terminal control towers. All instrument approaches were non-precision approaches, normally made on low frequency homing beacons.

The operation began in April 1942, and lasted until November 15, 1945, a period of approximately 3 years. The first operation occurred when the U. S. Army 10th Air Force, based in the Assam Valley, hauled gasoline and oil from India to China for refueling the Doolittle Raiders following their raid on Tokyo.

The main Hump operation started in May 1942, from far western India, with 27 DC-3 aircraft (converted U. S. airliners) and approximately 1,100 support personnel provided by the USAAF Ferry Command who were attached to the 10th AF. During the first two months of operation 96 tons of supplies were carried to China. Additional Douglas C-47s were provided for the operation later in 1942 and in early 1943. During the early days flights were generally conducted as daytime, VFR operations.

In summer of 1942 the operation was moved to newly constructed U. S. bases in the Assam Valley. On December 1, 1942, the primary responsibility for the supply operation was assigned to the USAAF Air Transport Command (ATC). New twin engine Curtis C-46s and Consolidated C-87s and C109s (converted four engine B-24s) began to arrive in the spring of 1943, aircraft better suited for high altitude flying. Douglas C-54 four engine aircraft began operations in the fall of 1944. All aircraft were unpressurized and crews were required to wear oxygen masks at high altitudes.

Living conditions in the humid, jungle-like atmosphere of the Assam Valley were very primitive. Personnel lived in tents and bamboo bashas. Food was military C-rations as no eating off base was permitted for health reasons. Dysentery and malaria were always health threats. All drinking water had to be purified before use. Personnel had to sleep in mosquito net covered beds. Entertainment was very limited.

During July 1945, the last full month of operation, approximately 71,000 tons of supplies, consisting primarily of gasoline, aircraft parts, bombs and ammunition, and other miscellaneous supplies required for maintaining U. S bases in China and in support of the Chinese armed forces, were flown over the Hump. During the lifetime of the operation over 650,000 tons of supplies were delivered to China by air.

In August 1945, the operation consisted of 622 aircraft, 34,000 military personnel and 47,000 civilian employees. Final 1945 official figures by the ATC Search and Rescue group listed operational losses during the operation at 509 aircraft crashed and 81 aircraft missing. Their statistics also listed 1,314 crewmembers killed, 1,171 crewmembers as having walked off the Hump after bailout, and 345 were still missing. There are still missing crewmembers resting on the Hump to this day.

Other aerial supply operations over and around the Hump area were conducted by the Troop Carrier and Combat Cargo Commands of the 10th Air Force, Air Transport Squadrons of the 20th Air Force and combat operations by the 10th, 14th and 20th Air Forces. These operations were conducted primarily in support of their Command objectives.

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