After the expansion of U-Tapao Royal Thai Navy Airfield in 1966, most American units and personnel were transferred from Don Muang, however, a small USAF liaison office remained at the base until 1975.

In April 1961, an advance party of the 6010th Tactical Group, USAF, arrived at Don Muang at the request of the Royal Thai government to establish an aircraft warning system.

[3] In March 1962, a small detachment of F-102 Delta Daggers from the 509th Fighter-Interceptor Squadron, from Clark AB, Philippines were sent to Don Muang.

On 14 August 1962, an Able Marble F-101C was hit by Pathet Lao antiaircraft fire over the Plain of Jars, but managed to return to Don Muang where it successfully made a belly-landing.

[2]: 279  The 35th Tactical Group consisted of the following units: A detachment of USAF U-21s based at Don Muang supported MACT operations, and in 1964 these were joined by two CV-2 Caribous.

The United States was taking over the role of "protector" from France in the area and the fear was that communism would prevail over the democratic governments in the region.

In early-July 1964, a detachment of C-130Bs from the 6091st Reconnaissance Squadron based at Don Muang began flying "Queen Bee" communications intercept missions off the North Vietnamese coast.

Units assigned to Don Muang RTAFB were the following: By 1966, the USAF had established a major presence in Thailand, operating from six RTAF bases.

At Don Muang the USAF had stationed Strategic Air Command KC-135 tankers for refueling tactical combat aircraft over the skies of Indochina.

[6] The USAF 7th Air Force in Saigon wanted to have additional KC-135s in Thailand and the solution reached was to expand the U-Tapao Royal Thai Navy Airfield and base the tankers there.

In late-1971, the Thai Government allowed US personnel to enter the country direct to the remote RTAF bases without needing to transit Don Muang, further reducing USAF operations there.