Chapter 5 - Communications-Electronics, 1962-1970

The 54th and 53d Signal Battalions, supporting I Field Force at Nha Trang and II Field Force at a base camp called Plantation near Long Binh, were corps signal battalions, modified to operate in Vietnam. The main command posts of both the field forces, unlike those of corps, were semipermanent and did not deploy. There were also other differences between the operations of a field force and a doctrinal corps, and these differences were reflected in the communications that were provided to field force headquarters and corps headquarters in Vietnam.

The principal peculiarity of field force signal communications resulted from the need to supplant traditional wire with mobile multichannel radio relay systems across the miles that separated the base camps of the subordinate units. Multichannel radio systems were extended to lower levels than ever before. In some instances, multichannel service was provided as low as artillery battery level whereas, by accepted doctrine, normal corps systems terminate at artillery group level. Both corps signal battalions were capable of operating approximately eighteen multichannel radio relay links. It was normal to connect all U.S. combat troops and those of Free World Military Assistance Forces within the field forces' tactical areas of responsibility with the field force headquarters. In addition, it was common practice to employ circuits and systems of the 1st Signal Brigade's Corps Area Communications System to provide alternate routing.

Each of the two field forces had a distinct and separate method of employing the resources of the Corps Area Communications System to supplement the organic communications; each had a specific reason. The II Field Force, operating in the relatively flat and populous III Corps Tactical Zone, used the corps area circuitry as alternate routing for its own combat system. In essence, the Corps Area Communications System and the II Field Force's combat communications system were interconnected throughout III Corps

HON CONG MOUNTAIN SIGNAL SITE, focal point for integration of 1st Cavalry Division communications and 1st Signal Brigade's Corps Area Communications System.

Tactical Zone to the extent that each system could potentially provide 100 percent backup for the other.

On the other hand, I Field Force had the responsibility for II Corps Tactical Zone, which consisted of about one-half the area of the Republic of Vietnam, the largest and most mountainous tactical zone in the republic. Neither the 54th Signal Battalion of I Field Force nor the 1st Signal Brigade's corps area communications resources in II Corps Tactical Zone could alone provide the necessary command and control communications from I Field Force headquarters in Nha Trang to the various U.S. and other Free World Military Forces combat headquarters in the zone. Therefore a concept evolved under which the 54th Signal Battalion would provide the multichannel communications from the forward command post-be it a newly created landing zone for a multibrigade operation or a remote fire support base occupied by an artillery group-to a communication complex of a 1st Signal Brigade unit. From there the communications would traverse the Corps Area Communications System to Nha Trang and into the I Field Force

The combat communications systems of each division in Vietnam differed from the standard doctrine in separate ways. These departures from doctrine came about partly as the result of the difference in terrain and operating conditions throughout the country and partly because of the fact that each division was, in essence, "writing its own book" on counterinsurgency warfare. The order during 1966 was "search and destroy" and each combat division had its own way of conducting such operations. As a result, during the Vietnam War the various division signal officers continually tailored their signal battalions and adjusted their methods of operating.

During the period 1969-1970 when I enjoyed the pleasure of hosting a countrywide Signal Officers' Conference, I was constantly amazed and impressed at the divergence of opinion that appeared in any discussion regarding the solution to a common problem. This can be attributed not only to the different circumstances in which each senior communicator found himself, but also to the inventiveness and free thinking that the signalman has always displayed.

For the most part, each division signal battalion in action in Vietnam had the same mission. All these units were responsible for providing the command and control communications to the division's maneuver elements, to the direct support elements, and to the combat elements of the Free World Military Assistance Force operating in the division area. In addition, the signal battalions were required to use division resources to provide communications facilities in the various base camps, complementing those provided by the Corps Area Communications Systems, which handled the bulk of the administrative and logistical traffic.

In the Republic of Vietnam a division usually operated in an area of responsibility covering 3,000 to 5,000 square miles. Such an operating area was enormous as compared to the 200 to 300 square miles in which a U.S. Army division would operate in conventional warfare. In addition, the divisions in Vietnam frequently established battalion-size and occasionally company-size fire support bases, all of which had to be tied together with reliable, responsive communications to ensure quick reaction in an emergency. As

The mobile multichannel radio relay system was the backbone of division communications. Generally found in a division area were a dozen or two multichannel radio relay links that connected the headquarters with brigade and battalion command posts and fire support bases. As in the field force systems, the sole-user circuit requirement was extensive. On the average, approximately onethird of the total available circuits were restricted to sole-users, and the majority of these terminated at the division tactical operation centers. For alternate emergency routing of circuits, the divisions utilized the corps area communications systems wherever and whenever possible. During combat operations, when maneuver elements initiated their action from established base camps, the mobile radio relay links were extended to the area of combat action. Alternate routing and backup links were used extensively, and the field force and the corps area communications systems often provided needed assistance, especially for intelligence, logistic, and administrative communications.

In division signal battalions, personnel and equipment authorizations were modified in order to meet the huge requirements placed on them, but in all cases a great deal of support was necessary from the corps area communicators. The necessity to rely on the Corps Area Communications System for additional support was particularly true of the austere signal battalions of the airmobile divisions, which were streamlined lightweights designed for mobile, nomadic operations, but were caught instead in the semipermanent environment of combat support and fire support bases.

U.S. Army Special Forces were first employed in Vietnam in 1961. In the early stages of U.S. involvement in Vietnam, small detachments were deployed on a six-month temporary duty basis

To support the countrywide U.S. Special Forces mission, the signal company of the 5th Special Forces Group established secure radio teletypewriter links from the operational base at Nha Trang to the detachments and teams in each corps tactical zone. This primary system was supplemented by long-distance voice radio nets that virtually blanketed the country.

The U.S. Special Forces communications system was not the subject of much fanfare in Vietnam and was overshadowed by the elaborate fixed communications installations that appeared throughout the country. It is significant, however, that the longdistance high-frequency voice and teletypewriter radio nets of this system were the only means of contact with the outside world for many small Special Forces detachments. The communications operated and maintained by the signalmen of the 5th Special Forces Group were independent of any other U.S. system in Vietnam.

What happened in the battle for Dak To, near the Cambodian border in central Vietnam in November 1967, illustrates not only the responsiveness of the U.S. Combat communicator during a fluid and furious engagement, but also the interconnection and mutual support which the division and field force signal battalions and the 1st Signal Brigade's area battalions continually provided for each other throughout the Vietnam War.

The battle of Dak To was not a separate operation in itself but occurred within the boundaries of the U.S. Army 4th Infantry Division's Operation MACARTHUR. Nevertheless, the size of the two opposing forces, the length and violence of the engagement, and the over-all significance of the battle have made the events that oc-

In late October U.S. reconnaissance revealed the presence of the North Vietnamese Army's 1st Division, with its four regiments supported by a rocket artillery regiment, deployed between Dak To and the common border area of Vietnam, Cambodia, and Laos. U.S. intelligence information pointed toward an imminent North Vietnamese Army attack on Dak To. To meet this threat, Major General William R. Peers, Commanding General, 4th Infantry Division, on 1 November sent his 1st Brigade with an attached battalion of the 173d Airborne Brigade to positions just west of Dak To.

When immediate contact was made with the enemy and heavy fighting ensued, the I Field Force commander, Lieutenant General William B. Rosson, provided General Peers with more troops and support. The remainder of the 173d Airborne Brigade arrived in the Dak To area on 5 November. The next day the 4th Infantry Division established a tactical command post at Dak To to control the two subordinate headquarters. The buildup of forces, which included significant numbers of combat support and logistic units, continued until the 18th, when Colonel Donald V. Rattan's 1st Brigade, 1st Cavalry Division, joined the battle, establishing its battlefield command post at Polei Kleng, near Kontum. By then the fighting was spreading to the west as the North Vietnamese forces were destroyed or pushed back into their sanctuaries in Cambodia and Laos. (Map 4)

The furious action around Dak To during the month of November, together with the fact that a force of U.S. Combat and support troops constituting more than a complete U.S. division had been committed, posed some problems to the 4th Infantry Division signalmen. For example, while the 124th Signal Battalion, commanded by Lieutenant Colonel William M. Spitz, was busy establishing a complete division communication system in the Dak To battle area, it also had to maintain its previously established network at Pleiku and take care of the rest of the division area in 11 Corps Tactical Zone. The enemy made sure that his presence would not be forgotten elsewhere by stepping up attacks by fire and ambushes throughout the entire Central Highlands. In a classic example of combat communications support, the 124th Signal Battalion successfully met the challenge by judicious use of its own resources, as well as those provided by I Field Force's 54th Signal Battalion and the 43d Signal Battalion of the 1st Signal Brigade.
The 124th's initial effort in support of the battle of Dak To

FIRE SUPPORT BASE ON A RIDGE NEAR DAK To. Tall antennas were used to extend range of mobile voice radios.

was the installation of two 12-channel links from the division main command post at Camp Enari near Pleiku to the division's 1st Brigade forward command post at Dak To. Upon arrival of the division tactical command post at Dak To, on 6 November, the battalion was operating a mobile, one-position switchboard for the 1st Brigade of the 4th Division. With the increase in activity it became necessary to install a second switchboard for the division tactical command element. This second switchboard, like the first, was shortly saturated; it became apparent that the 1st Logistical Command's forward support activity, airfield control personnel, and other support units, continually arriving by air and road, all had a need for area communications support. The Division Signal Officer made a request to Headquarters, I Field Force, for area service in order to relieve the increasing pressure on his two small mobile switchboards and the command and control teletype circuits which his signal battalion had activated. As a result, the 1st Signal Brigade's 43d Signal Battalion, under the command of Lieutenant Colonel Edwin B. Gentry, installed area telephone and message

service at Dak To as well as a 12-channel general-user link from Dak To to Pleiku. Thus relieved of area service responsibility, the communications resources of the 124th Signal Battalion could and did remain oriented toward the command and control effort.

Some of the largest demands for circuits over the systems provided by these three battalions were to support U.S. air operations. Not only was there a need for extensive communications at the Army airfields but there was also a requirement for air route traffic control and point-to-point close air support circuits. Finally, significant numbers of channels were needed to control and guide the large bomber effort directed by General Westmoreland. The extensive requirements for communications in support of air operations were not confined to this battle, but were typical of most other operations in Vietnam.

As the battle reached a peak in mid-November, the area system between Dak To and Pleiku proved insufficient. The 1st Signal Brigade thereupon made arrangements to install a 24-channel tropospheric scatter system with mobile equipment between Dragon Mountain, adjacent to Camp Enari, and the U.S. Advisers compound, which stood next to the village of Tan Canh and had been consistently used as a radio relay site into the Dak To airfield. Of these twenty-four channels, the 124th Signal Battalion was to use twelve in direct support of the 4th Infantry Division. In order to extend these circuits to the division tactical command post at the airfield, the 124th's linemen installed a 12-channel landline carrier system using spiral-four cable. This four-mile link was one of the relatively few cable systems installed outside the perimeter of U.S. camps in Vietnam. Usually radio relay would have been used, but in this case the 4th Infantry Division signalmen had simply exhausted the supply of radio equipment.

In all, during the thirty-three days of the battle for Dak To, over fifteen multichannel links were installed and operated in di-