As the Nixon administration sought to move the conflict in Vietnam from the battlefield to the conference table, the first major U.S. Army combat elements began to withdraw. The withdrawal began in July 1969 with the 9th Infantry Division, followed closely by the 3d Brigade of the 82d Airborne Division, and ended with the 196th Light Infantry Brigade in June 1972. (Table 1)

OCTOBER 1970 - JUNE 1972

Unit    Date
3d Brigade, 9th Infantry Division    October 1970
199 Infantry Brigade    October 1970
1st & 2d Brigade, 4th Infantry Division    December 1970
25th Infantry Division (-2d Brigade)    December 1970
11th Armored Cavalry Regiment    March 1971
2d Brigade, 25th Infantry Division    April 1971
1st Cavalry Division (-3d Brigade)    May 1971.
1st Brigade, 5th Infantry Division (Mechanized)    August 1971
1734 Airborne Brigade    August 1971
23d Infantry Division (-196th Infantry Brigade)    November 1971
3d Brigade, 101st Airborne Division    December 1971
1st Brigade, 101st Airborne Division    January 1972
2d Brigade, 101st Airborne Division    February 1972
3d Brigade, 1st Cavalry Division    June 1972
196th Infantry Brigade    June 1972

Historical records reveal little that was unusual about division level communications as units withdrew. As a general rule, units and their signal support elements collapsed into some central staging area and their communications mission was gradually transferred to units of the First Signal Brigade. This procedure permitted organic signal units to leave with the major combat elements they were supporting. The experience of the 3d Brigade of the 82d Airborne Division is typical. The 36th Signal Battalion of the First Signal Brigade moved into the 82d's area during the phase-out period and established a residual communications


network that permitted the organic signal units to be withdrawn. Most of the combat units that phased out in this manner mentioned three problems in their after-action reports.

The first was maintaining high morale when the future of the unit was uncertain. In many instances units did not know where they would end up; some, in fact, were inactivated soon after they left Vietnam.

The second problem was turning in equipment, which often had to be split three ways: one part was transferred where it stood to Vietnamese forces; another part was turned in at a depot; and the third part was retained. Instructions often came at the last minute. Frequently the "pack rat" syndrome produced much more equipment on hand than unit records showed. Central distribution points had to be established so that a unit could turn in all of its equipment by a scheduled departure date. Many soldiers keep anything which their experience tells them might be useful later. Since some of the major combat units had been in Vietnam a long time, there were some large hoards of "auxiliary" equipment.

The third problem was excessive personnel turbulence. `Trying to identify the troops who were to remain behind and those who were to leave was cumbersome in light of the various personnel policies then in effect. This and other problems frustrated both the administrators and the affected soldiers during the phase-out. It is to each unit's credit that, by and large, the debarkations went smoothly and remained fairly close to the established schedule.

The withdrawal of the major U.S. combat elements did not presage the end of hostilities. The fight was to be carried on by units of the South Vietnamese Army with logistics and air support provided by the United States from outside Vietnam. Channels for this assistance had to be maintained in the four military regions where the fighting was continuing, and communications support was a vital factor during the final months of combat.

To ensure adequate support to the South Vietnamese forces after the withdrawal of the American combat troops, a regional assistance command headquarters was set up in each of the four military regions. Its commander, normally a major general, worked closely with the senior South Vietnamese military commander in the region on coordinating close air strikes, logistics support, and other combat support which the United States was obligated to provide. Since all of -the signal units organic to the major combat elements had been withdrawn, communications support to these four U.S. regional assistance commanders had to be provided by residual signal units of the First Signal Brigade.


This communications network, austere by comparison with that provided for American combat units, was vital because it was the only link between the U.S. commanders in the four districts and the residual headquarters elements in Saigon, which could coordinate to direct air strikes and logistics support where they were needed. A signal unit, roughly of company size and commanded by a captain, provided signal support in each of the four military regions. The unit generally provided a switchboard to serve the regional U.S. commander and his staff, a simple communications center through which messages could be handled, and, perhaps most important, a narrow-band secure voice terminal to permit the U.S. commander to call in air strikes through the joint Operations Center in Saigon. The telephone and communications center functions were relatively clear-cut and caused few problems. The circuits went to the closest entry point in the fixed backbone system that spanned Vietnam and which was at that time being run under contract by the Federal Electric Corporation. From there the circuits rode the system to the residual headquarters in Saigon.

The requirement for secure voice communications was, however, another matter. If the Vietnamese commander was working from his main headquarters, the U.S. commander could track him without much difficulty and call in the close air support missions as needed. The system was set up so that the commanding general had to place the call and request the mission himself. The narrowband voice equipment traversed the fixed backbone network to the close air support center in Saigon, which called for missions from either Thailand or Guam as circumstances dictated. When a Vietnamese commander moved to the field, however, the process became more complicated. Then the U.S. commander had to stay with him and, from whatever his location, place an immediate secure voice call all the way to the operation center in Saigon. He often had to use tactical FM radio equipment and rely on retransmitting because of long distances and terrain obstacles.

Some of the most demanding secure voice communications missions were placed on the system after the majority of U.S. tactical communications units and equipment were gone. To meet this demand, FM retransmission aircraft began flying almost continuous missions, in the first and second military regions where the mountainous terrain and enemy activity were heavily taxing the Vietnamese forces. These U-21 aircraft stayed in continuous orbit on station until they had to refuel. This technique gave the commanders in all four regions a secure way to call in close air strikes from almost any location.


At this time the First Signal Brigade, which had once boasted over 25,000 troops, consisted mainly of a management office that monitored the contractor's waning operation and his maintenance of the backbone communications system. It also monitored the 39th Signal Battalion in Saigon, which provided minimal communications support to the remaining Military Assistance Command headquarters and to the signal units in each of the four military regions.

The final phase withdrawal was the departure of the regional assistance commands themselves; the four signal units that supported them were the last elements to go. About the same time, the colors of the First Signal Brigade were officially retired and transferred to Korea.



Go to:

Previous Chapter

Next Chapter

Return to Table of Contents

Last Updated 3 October 2003

Return to CMH Online