Declassified: Turning Cargo Planes into Gunships

 

This material was formerly classified and restricted to authorized personnel on a strict need-to-know basis. Its contents were withheld due to operational sensitivity. Following formal declassification and review, it is now released for public record.

For years, much of what happened over the Ho Chi Minh Trail in Laos remained hidden from public view. The United States was officially not at war in Laos, and operations there were conducted under layers of classification tied to what later became known as the “Secret War.” Details of gunship operations, basing in Thailand, mission results, and even the existence of certain aircraft variants were restricted at the time and discussed only within narrow operational channels. It was not until years later, through declassification, official Air Force histories, and the accounts of participants, that the full scope of these cargo aircraft turned gunships and their role over Laos became public.

In the late 1960s, over the jungled spine of the Ho Chi Minh Trail in southern Laos, U.S. airmen did something that sounded like science fiction at the time. They turned lumbering cargo aircraft into lethal night-firing gunships. The effort, formally organized under Project Gunship I and Project Gunship II, became one of the most audacious improvisations of the Vietnam War and left a permanent mark on modern airpower.

 

The story begins with the C-47 “Gooney Bird,” a World War II-era transport aircraft that had already served as a paratrooper carrier, medevac platform, and flare-dropper. In Vietnam, Air Force officers realized that if a C-47 could be held in a steady, banked turn over a target, its weapons could be fired sideways in a continuous stream. Under Project Gunship I, engineers mounted three 7.62 mm miniguns along the left side of the aircraft, creating the AC-47, nicknamed “Spooky” and later “Puff the Magic Dragon.”

By 1969, four AC-47s were deployed to Laos, where they proved devastating against truck convoys and ground forces moving along the Ho Chi Minh Trail. Their success prompted a follow-on effort to expand gunship operations in Laos. An initial plan to convert Laotian-owned C-47s proved logistically difficult, so the United States instead supplied modified South Vietnamese C-47s for use by the Royal Laotian Air Force.

These AC-47-type aircraft flew night interdiction and close air support missions, adding another layer to the already complex and largely covert air war over Laos.

The real leap came with Project Gunship II, which transformed the larger C-130 Hercules into the AC-130 gunship. At Wright-Patterson Air Force Base, engineers cut weapon ports into the fuselage and installed 20 mm and 40 mm cannons. Later versions added a 105 mm howitzer, turning the aircraft into a flying artillery platform capable of delivering sustained, accurate fire.

The first AC-130A aircraft arrived in Southeast Asia in late 1968 and were quickly committed to combat from Ubon Royal Thai Air Base. Flying night missions over southern Laos, they operated as part of Operation Steel Tiger and Operation Commando Hunt, the major interdiction campaigns aimed at North Vietnamese logistics along the Ho Chi Minh Trail. In this role, the AC-130s destroyed hundreds of trucks and disrupted enemy supply lines in ways conventional strike aircraft could not consistently achieve.