P-47D Thunderbolt 42-28152 of the 1st Air Commando Group

The 1st Air Commando Group (1st ACG) was a unique and innovative military unit created to support deep penetration missions behind enemy lines in Burma during World War II. It was formed under the leadership of Lt. Col. Phillip G. Cochrane and Lt. Col. John R. Alison, chosen by General Hap Arnold to develop a new type of organization tailored to support the British Chindits, a long-range penetration force.

Formation and Composition

Initially organized as the 5318th Provisional Air Unit, the 1st ACG was conceived as a self-sufficient “mini air force,” with its own dedicated fighters, bombers, transport aircraft, gliders, liaison aircraft, and even Sikorsky XR-4A Hoverfly helicopters for a brief period. The unit eventually consisted of:

30 P-51 Mustangs (fighters)
14 C-47 Skytrains (transports)
Over 100 CG-4 gliders
A number of North American B-25 Mitchell bombers

Mission and Operations

The 1st ACG’s mission was closely integrated with the Chindits, and it played a crucial role in Operation Thursday, the air invasion of Burma. This operation involved towing gliders carrying British and Indian troops behind enemy lines to establish forward bases, from which they could launch further operations. Key points of the mission included:

Preliminary Attacks and Reconnaissance: Starting in February 1944, the unit conducted raids targeting bridges, warehouses, locomotives, and communication lines. P-51s and B-25s also performed reconnaissance missions to locate landing zones and identify targets for bombing.
Glider Insertion: On March 5, 1944, the operation commenced, with C-47s towing gliders towards two designated landing sites, Broadway and Piccadilly. Due to a last-minute reconnaissance, Piccadilly was found obstructed, leading to all forces being redirected to Broadway. Despite challenges, including difficult terrain and glider crashes, the operation succeeded in establishing a landing strip and inserting 539 men and equipment.
Continued Operations: The unit continued to support the Chindits by conducting supply drops, airlifting additional troops, and providing air cover. They also engaged in direct combat, with fighters and bombers targeting enemy airfields and infrastructure.

Tactical Innovations

The 1st ACG developed several unique tactics:

Dive Bombing: Mustangs performed dive-bombing missions, using bombs and depth charges against hardened targets.
Cable Cutting: An innovative method using a cable and weights suspended from P-51s to cut Japanese communication lines.

Achievements and Impact

The 1st ACG’s operations were marked by significant achievements:

Inserting over 12,000 troops and 2,000 mules behind enemy lines.
Conducting between 5,000 to 8,000 sorties, with over 2,000 casualties evacuated and zero light aircraft losses due to enemy fire.
Destroying 90 enemy aircraft in the air and 44 on the ground, with only six of their own aircraft lost.

Despite its success and the critical role it played in the Burma campaign, the 1st ACG was gradually absorbed into more conventional air force structures, though it was not formally disestablished until November 1945.