On 19 September 1966, by Fifth Army General Order #236, the 189th Aviation Company (Air Mobile Light) was activated by the Department of the Army to be organized on 1 November 1966, at Ft. Carson Colo. On 9 December 1966, the 189th was reorganized under T O & E 1-77G (Modified) and was established with a headquarters platoon, two airlift platoons, a gun platoon, and a service platoon. The unit was provided additional support by the 604th Maintenance Det, the 519th Medical Det, and the 6th Signal Det. From 9 December 1966 to 1 March 1967 the unit trained for deployment to the Republic of Vietnam at Fort Carson Colo. From 16 March to 21 April the company departed Ft. Carson for Sharp Army Depot California enroute to Vietnam. The unit arrived at Cam Rahn Bay on 25 April 1967. From Cam Rahn the company was sent to Pleiku where it arrived on 27 April. On 15 June the unit became operational as part of the 52nd Avn Bn Cbt, and was given the mission of supporting the 4th Infantry Division, 5th Special Forces, as well as local regional/popular forces. The missions assigned were command and control, resupply, and combat assault. On 1 April 1969 the unit was redesignated the 189th Avaition Company (Assault Helicopter).

  The company adopted the call sign "Ghostrider" for the airlift platoons and "Avenger" for the gun platoon. Both the "Ghostriders" and "Avengers" have earned the respect of all units in the central highlands. In 1967 they fought at Dak To I. In 1968 they participated in the battles at Dak To I and in the Dak Poko Valley. In 1969 the significant battles were fought at Ben Het and Dak To II. In 1970 they were a key element in the allied success at Dak Seang, and later in May they spearheaded the Cambodia offensive with Major George A. Morgan as Air Mission Commander. Most recently they were the first company in the Central Highlands to give combat training to Vietnamese Air Force (VNAF) pilots. In this program the 189th has excelled and surpassed all expectations setting the standards for the entire 1st Aviation Brigade. Even though the 189th is going home, the 229th VNAF Squadron, which was trained by the 189th will carry on with the Ghostrider spirit.