A standoff attack has been defined as an attack using 'a weapon launched at a distance sufficient to allow the attacking personnel to evade defensive fire from the target area'. The prime requisite of standoff weaponry is superior mobility. Whilst the NVA were very aware of the importance of fire support, their particular war of mobility forced them to travel light and despite all the differences in weapon characteristics, all NVA/VC mortar, recoilless rifle, and rocket units shared one key attribute – superior mobility. The weapons themselves and the ammunition could be man-packed to just about any launch location.
The NVA/VC considered US and Government of Vietnam (GVN) military installations as being both vulnerable and lucrative targets and that standoff attacks against these installations allowed them to accomplish the following objectives:
This philosophy was supported to some extent by a prisoner of war, a rocket company commander, who made the following statement while being interrogated in 1968:
There were a number of weapons in the NVA arsenal that met both the definition and fitted the philosophy of standoff attacks:
Recoilless rifles, whilst effective, were nonetheless extremely vulnerable and could not properly evade defensive fire unless only a few rounds were fired and the crew dismantled the position rapidly.
Mortars, particularly the heavier 81/82mm with their greater range, were were generally pre-sited in emplacements and aimed at specific targets which were generally not mobile (e.g. base camps, airfields etc). Ammunition was brought in by a crew and rapidly fired. The crew then hid the mortar and fled on foot. In many cases, mortars employed in this role were often spotted by allied aircraft and destroyed in-situ before having fired off their basic load. The smaller, 60mm mortar, was much more suited to the role of standoff attack and met the 'high mobility' definition.
In the fight against the French in the First Indochina War, pack howitzers had played a decisive role. In the war against the Americans however, pack howitzers could only be used in areas where US airpower could not strike within forty minutes and by 1966 there was nowhere in South Vietnam that met this criteria. As US airpower became increasingly pervasive these weapons, that had to be transported by pack animals, disappeared from the battlefield. Besides, the Chicom 70mm howitzer weighed nearly four times as much as the 81/82mm mortar, had less explosive power and about the same range. It was not therefore an adequate standoff weapon.
The overwhelming presence of US airpower also meant that heavier mortars and artillery were generally not sited for use in South Vietnam but rather fired from Laos, Cambodia or North Vietnam.
Over time, the most effective standoff weapons proved to be man-transportable rockets.
Regimental and Battalion Weapons
Mortar, recoilless rifle and heavy machine gun companies were organic to infantry combat support regiments and were employed at all echelons as combat support units. A typical infantry combat support regiment was assigned an 82mm mortar company, a 12.7mm heavy machine gun company and a 57/75mm recoilless rifle company. Each of these companies was officially authorized six weapons and approximately 80 personnel although these numbers were often exceeded. These companies were supported as required by one signal and one reconnaissance company organic to the regiment. The subordinate battalions were also armed with 60mm mortars, some 81/82mm mortars and a few 57mm recoilless rifles.
Mortars and Recoilless Rifles were employed as separate standoff attack forces, as a composite force, or in conjunction with rocket standoff attacks.
When employed as individual weapons systems, care was exercised to position these weapons in a relatively well concealed area. They were known to have been positioned within hamlets, at the edge of small villages, in churchyards or in close proximity to individual dwellings. The capability of allied counterfire appears to have been the key to their method of employment.
When employed in conjunction with rocket standoff attacks, where no attempt to breech the installation defenses was planned, mortar and recoilless rifles were normally employed as follow-on fire to the initial rocket attack. When used in this manner, they were normally employed as cover fire while the rocket force withdraws. The recoilless rifle unit was usually the last to withdraw.
A prisoner of war interrogated in December 1963 stated that recoilless rifles and mortars were more accurate than rockets and therefore could be used against smaller targets. He stated that except for the difference in range, they were used in a fashion similar to rockets.
Standoff Rocket Bombardment
By 1966, rockets began to dominate over mortars as the NVA's standoff weapons of choice. Their light-weight, salvo fire capability, and increased explosive power, meant they could be more flexibly employed and substantially increased the standoff threat. This threat was further enhanced by the fact that the standoff range of the 120mm mortar, 5,700-meters, was doubled by the range of the 122mm rocket, 11,000-meters.
Rocket Units were organized into regiments, battalions, companies and platoons. Each regiment was assigned a headquarters squadron, a signal and reconnaissance company and three rocket battalions. Within a typical rocket battalion there was a headquarters company and three rocket companies. Each 122mm rocket company was authorized six launchers and 18 rockets. The 107mm rocket company was normally authorized 12 launchers and 24 rockets. The 140mm rocket company was normally authorized 16 launchers and 16 rockets. All rockets could be employed from improvised launchers. When employed in large-scale standoff attacks, rocket units were often supported by elements of an infantry combat support regiment.
It was usual for mortar and recoilless rifle units to operate separately from rocket units, but sometimes they worked together in varying combinations. If they were used as part of the same standoff attack, they were fired sequentially in the order; rockets, mortars, recoilless rifles, RPGs and MGs.
In support of direct attacks against allied positions, rockets and mortars were used to fire on area targets such as ammo dumps, aircraft parking areas, fuel dumps and troop cantonments. The recoilless rifles and other direct firing weapons would hit point targets such as bunkers, weapons positions and command and communications centers.
Prior to a standoff attack, and in keeping with the NVA practice of thorough preparation, the NVA would conducts a thorough reconnaissance of the installation.
Each installation to be attacked was normally reconnoitered at least three times before the attack. The reconnaissance element normally consisted of three teams of three individuals each. Intelligence agents and recon units would scrutinize the target and visit it several times. Reconnaissance entailed a detailed analysis of the installation proper to determine the location and disposition of critical equipment and facilities, the location and manning of command posts, the number and type of perimeter and internal defense positions, and the schedule of installation operational activities. Efforts of the reconnaissance element were often supplemented by enemy agents (male and female) located on and off the installation.
After studying the reports by the reconnaissance element, final reconnaissance of the target was normally conducted by the rocket force company commander prior to making final decisions and preparation for attack.
In order to maintain maximum security, it was normal for the the launch crews not to be informed of any details regarding the operation ahead of time. They were guided to the sites unaware of the exact time of the attack or location of the launch site.
Point targets within the target area were precisely identified and individual standoff weapons resources were allocated to it. After that, an operational plan was drawn up which included the date and time each of the following actions was to occur:
Weapons Site Preparation.
Using the reference stakes placed by the survey team, the launch crews positioned and aligned the rocket or rocket launchers and double checked against survey party calculations. The rocket launcher firing pits were prepared and dug out and the rocket launch systems were wired for firing. Once all of these preparations was completed, the rockets were finally loaded into position.
Rockets were grouped into firing batteries of six rockets and located twenty meters from the other rocket groups. Within each firing battery, rockets were individually spaced ten meters apart. Total time to prepare rocket launch positions, after arrival of the rocket launch crews, varied from 20 minutes to an hour, dependent upon the size of the force and the type of launchers being used.
Employment of mortar and recoilless rifles required preparations similar to those required to fire rockets, except the aiming stakes were normally 20 to 30 meters in front of the firing position. Weapons positions were normally established in a semicircular pattern with the smaller caliber mortars forward of the larger caliber mortars and the recoilless rifles on the flank of the larger caliber mortars. Mortars were usually positioned in a circular foxhole 1.7 meters deep and two meters wide with a dirt bank around the position. This position was usually camouflaged with branches, grass or other like material. Recoilless rifle positions were usually located on high points offering concealment.
Weapons were transported from the resupply point to the staging area by sampan, foot, or both, using military transportation personnel and/or civilian porters. Movement from the staging area to the launch site was accomplished, with few exceptions, at night and by foot. The staging or assembly area was seldom more than one and one-half hours travel time from the launch site and in some cases, was as close as three to five hundred meters to the launch site. Movement of the 122mm rocket is best illustrated by excerpts from an account given by a prisoner of war captured on 25 June 1968 who had participated in numerous 122mm rocket attacks against military installations. As related by the prisoner..
This same POW stated that he did not know how the rockets were transported to the resupply or staging location. However, other prisoner of war reports reflected that rockets were transported to staging areas or resupply points by a combination of military and civilian porters or by a combination of sampans and porters. These movements were conducted in daylight under cover of heavy foliage. If insufficient foliage cover existed then the movements would be conducted at night.
Staging areas were normally within one to two hours foot or sampan travel from the launch site. Exceptions to this were mortar units which supported battalion size operations involving a combination of standoff and sapper attacks on an installation. These movements were usually by foot and required up to two hours travel time from the staging area, dependent upon the distance to the launch site. However, in some cases weapons would be located adjacent to the launch site itself.
From five to 30 days preceding an attack, the NVA normally attempted to locate his weapons approximately three to five kilometers from the launch site. In some cases, these storage points were used as assembly or staging areas which are normally one to one and a half hours travel time from the launch site. In other cases, these storage areas may be located along river or stream banks adjacent to the launch site, in graveyards, abandoned villages or hamlets, astride boundary lines between US, RVNAF or FWMAF field units, in tunnels, or adjacent to or within inhabited areas, dependent upon the attitude of the civilian populace. In each case, maximum effort was made to conceal these locations by natural foliage or similar methods.
In his book 'Lima-6, A Marine Company Commander in Vietnam', R D Camp describes how his Marine rifle company discovered a rocket launching site near Khe Sahn:
Attacks by rockets usually lasted from two to twenty minutes dependent upon the size of the attacking force, the number of rounds available, and opposing counterfire response capability and accuracy.
If counter-fire reaction was slow, fire adjustment was made after the first two or three registration rounds. Forward observers, near the target area, called in launch data corrections to the rocket commanders by radio or field telephone.
NVA rocket units were organized into regiments, all of whose rockets could be fired from improvised launchers. Each regiment contained a headquarters company, a signal and reconnaissance company and three rocket battalions. Each rocket battalion included a headquarters company and three rocket companies.
In an attack against Da Nang Airbase in February 1967, one hundred and thirty 140mm rocket launchers were emplaced at a single launch site. Because of malfunctions in the firing system and individual rocket motors, only 66 were successfully launched of which fifty-six impacted on Da Nang Air Base and eight hit an adjacent village. The other two fell harmlessly outside of the target area.
In large standoff attacks, infantry weapons units protected the rocket sites. The potential reaction time and firepower of allied counter action by fixed-wing aircraft, helicopters, and artillery determined how long rocket attacks lasted. However, rocket attacks usually lasted two to twenty minutes depending on the availability of antiaircraft protection for the launch sites, the size of the assault force and ammunition availability. As the war progressed, rocket attacks increased in both ferocity and duration.
As a result of the increasing success of allied countermeasures, the NVA began to use new tactics for standoff attacks by attacking military installations from more than one launch site location, either simultaneously or by alternating salvos, in an attempt to increase the problem of counterfires. The reasoning behind these tactics was probably explained best by the captured rocket company commander, interrogated in December 1968, when he stated:
NVA rocket troops soon learned that they had to follow these 'rocket raid rules' if they were to survive.
Withdrawal from the launch site was planned in advance. The withdrawal routes for rocket units were planned to provide for concealment by the most direct route to the assembly or staging area. This route was normally the same as that used to reach the site. At night, emphasis was placed on speed. When a large rocket force was employed and its units were pursued, mortars would be used to give fire support during the withdrawal.
US Army Military Assistance Advisory Group Vietnam (MAAG) - Lessons Learned No. 71 Countermeasures Against Standoff Attacks (March 1969)
Secrets of the Viet Cong J W McCoy, Hippocrene Books 1992, ISBN 0-7818-0028-5
Inside the VC and the NVA Michael Lee Lanning & Dan Cragg, Ivy Books 1994, ISBN 0-8041-0500-6
Vietnam Weapons Handbook, David Rosser-Owen, Patrick Stephens Limited, 1986, ISBN 0-85059-838-9
Infantry Weapons of the World, Christopher F. Foss and T.J.Gander, Ian Allen Ltd., 1977, ISBN 07110-0734-9
'The Vietnam Experience', Orbis Magazine Collection
Warsaw Pact Infantry and its Weapons, edited by J.I.H. Owen, Brassey's Publishers Ltd., 1976, ISBN 0-904609-03-0
Weapons and Tactics of the Soviet Army, David C. Isby, Janes Publishing, ISBN 0-7106-0089-5