U.S. ARMY AIR-TO-GROUND (ATG) MISSILES IN VIETNAM

By Dr. Kaylene Hughes, AMCOM HistoryFebruary 6, 2017

TOW Missile
(Photo Credit: U.S. Army) VIEW ORIGINAL

In 1995 the Base Realignment and Closure (BRAC) Commission recommended that the U.S. Army Missile Command (MICOM) and U.S. Army Aviation and Troop Command (ATCOM) be combined into a new U.S. Army Materiel Command (AMC) major subordinate command at Redstone Arsenal to be known as the U.S. Army Aviation and Missile Command (AMCOM). The new organization stood up provisionally almost 20 years ago, on Jul. 17, 1997.

Decades before this decision, however, ATCOM, MICOM and their predecessor commands had joined forces to accomplish higher headquarters guidance on the arming of certain rotary wing aircraft assets deployed during the Vietnam War.

One of the earliest examples of the new firepower envisioned for Army helicopters in the years after the Korean War ceasefire was the Aircraft Weaponization Program, which consisted of 2.75-inch rockets divided evenly between two rocket launchers mounted on either side of the helicopter. Originally developed for the U.S. Navy (USN), the folding fin aerial rocket (FFAR) was used to arm the Army's UH-1A/1B/1C/1M Iroquois ("Huey") and AH-1G Hueycobra helicopters in Vietnam.

The Army's effort to adapt the widely used rocket, originally designed to be launched from a high-performance fixed wing airplane traveling at a higher speed unmatched by helicopters in the early 1960s, first required researchers "to modify the rocket to obtain a spin in order to achieve stability upon launch by averaging thrust misalignment." In Apr.1961, the Army Aviation Board, in conjunction with the Ballistics Research Laboratories (BRL) at Aberdeen Proving Ground, Maryland, evaluated 200 modified 2.75-inch rockets using the H-21 Sioux helicopter as the weapons platform.

After determining that the rocket was suitable as a rotary wing armament, one of AMCOM's predecessors, the U.S. Army Ordnance Missile Command (AOMC) at Redstone Arsenal, Ala., developed and fabricated a 2.75-inch rocket subsystem for use on an H-34 Choctaw helicopter assigned to the Aviation Board. About a month after receiving the equipment on Aug. 28, 1961, the board initiated testing on the 2.75-Inch (Modified) Aerial Rocket Weapons System.

During the four-month evaluation conducted from Sept. 21, 1961 to Jan. 21, 1962 at Fort Rucker, Ala. and Fort Sill, Okla., AOMC furnished technical assistance such as fully instrumenting systems being tested as well as fabricating replacement items to eliminate identified problems. The Missile Command's research and development laboratory also studied shortcomings such as launch pod corrosion after firing and provided recommendations on preventive measures.

Although the Army never deployed Choctaw helicopters to Southeast Asia for use in combat by its own aviators, the CH-34, originally designed by Sikorsky for the USN as an antisubmarine warfare (ASW) platform, the helicopter served in Vietnam with the U.S. Marine Corps (USMC) from 1962 to 1969, while the Army supplied about 100 of the aircraft to the South Vietnamese air force.

However, it did begin arming its first Huey gunships with the aerial rocket system in mid-1962. Combined with machine guns to supply suppression fire, the 2.75-inch rockets delivered what USN Cmdr. David G. Tyler described in his 2003 article, "The Leverage of Technology: The Evolution of Armed Helicopters in Vietnam," as "a potent knockout punch."

The rocket's ten-pound High Explosive (HE) warhead's impact was similar to a 75-mm howitzer, while the 17-pound HE warhead introduced in 1968 was as effective as a 105-mm howitzer. Additional warheads such as the antitank (AT), white phosphorus (WP) used for marking targets, and ten-pound fletchette (WDU) which released over 1,000 small, arrow-shaped projectiles on impact, further enhanced the Army aerial gunships' battlefield presence. On Oct. 31 1962, the newly-established MICOM assumed industrial and field service responsibilities for the 2.75-inch missiles used by the Army in Vietnam.

Another ATG airborne missile system first deployed by the Army to Vietnam was the airborne M22 antitank missile subsystem. The Ordnance Guided Missile Center (OGMC) at Redstone Arsenal, another AMCOM predecessor, began following the development of the ground version of the French antitank missile system in Apr. 1952 in preparation for the possible assumption of technical supervisiory responsibilities if the Army decided to acquire the weapon.

Subsequently, on Feb. 16, 1959, the U.S. Army Rocket and Guided Missile Agency (ARGMA) at Redstone assumed management responsibility for the French designated SS-10 as an interim ground-launched antitank missile system. The SS-11, an ATG modification of the SS-10, was the first helicopter-mounted antitank missile in the world. Purchased in 1961, the armament subsystem was known as the M22 in U.S. Army nomenclature when the entire complement of six SS-11B missiles was installed on the UH-1B Huey helicopter.

The first MICOM managed M22 armament subsystems deployed to Vietnam in 1966 for use by the Army's first airmobile 1st Calvary Division, which had become fully operational in-theater in Sept. 1965. Army aviators successfully used the missile in combat on Oct. 9, 1966 during the campaign to pacify the Binh Dinh Province. The 2d Battalion, 20th Artillery (Aerial Rocket Artillery) of the 1st Calvary Division fired M22 missiles to destroy bunkers on the peninsula, resulting in the capture of 55 Viet Cong with no further fighting.

Missile operator difficulty in visually tracking a flare on the missile's tail and manually guiding it using a small control stick and an unspooling wire that transmitted commands was further complicated by the turbulence of actual air battle conditions. Despite these challenges, the Army deployed the M22 subsystem to Europe as well as made additional deployments to Southeast Asia in 1967 and 1972. After successfully being used against tanks and other targets, the subsystem returned to the United States in 1973. Eventually replaced by the airborne tube-launched, optically-tracked, wire-guided (TOW) missile system, the Army phased out the M22 subsystem from its regular inventory in May 1984.

The most significant Army Missile Command contribution to Army Aviation during the Vietnam War occurred in May 1972 when airborne TOW antitank missiles mounted on a UH-1B Huey helicopter destroyed four captured American M41 tanks, an artillery gun, and a truck.

Studies leading to the development of the XM65 TOW armament subsystem for the AH-1 series Cobra helicopter had started in 1970. Although the XM26 prototypes had undergone considerable engineering testing by the Hughes Aircraft Company and Bell Helicopter, they had never been given to the U.S. Army for service tests because the main attack helicopter developmental effort directed by the U.S. Army Aviation Systems Command (AVSCOM), an AMCOM predecessor organization, had shifted to the more advanced AH-56 Cheyenne weapons system.

In 1971, though, representatives from MICOM, Hughes Aircraft and Bell Helicopter assisted the German Army Aviation School in its evaluation of the TOW missile's suitability for use in an airborne role, thereby making the German military the first to test the XM26. Fired from various distances and under changing flight conditions against actual tank hulks positioned on the test range, the final shots using live warheads effectively demonstrated the potency of the airborne TOW.

The Improved Cobra Armament Program, which started in March 1972, involved the functional upgrade of the XM26 TOW/UH-1B Huey to the XM65 TOW/Cobra ATG weapon system. The launch of the "Easter Offensive" on Mar. 30, however, gave MICOM an opportunity to prove that the airborne TOW missile could be used as an effective weapon against the Soviet armor that supported the North Vietnamese Army's (NVA's) massive offensive across the Demilitarized Zone (DMZ). Included in the onslaught were several captured American tanks. This action generated an urgent but unprogrammed combat requirement for the TOW antitank weapon system. Both missile and aviation senior leaders understood an impressive showing would help secure the funding needed for the advanced attack helicopter (AAH) program.

On Apr. 14, 1972, the Department of the Army (DA) directed MICOM to remove the XM26 subsystem from storage and rush it and a load of TOW missiles to the battlefront in Vietnam. One week after receiving the order to deploy, three C-141 aircraft flew to Vietnam carrying two Huey gunships, two XM26 subsystems, missile crews and other equipment.

The TOW Project Manager, Col. Robert W. Huntzinger, headed the team effort and handpicked the MICOM technical support team that accompanied the equipment in-theater. Included in the support team were an expert on the UH-1B from Bell Helicopter as well as two engineers and two technicians from Hughes Aircraft, each an expert on the TOW and its airborne guidance and control equipment. A last-minute replacement pilot/gunner was obtained from AVSCOM's AAH program in St. Louis, Mo. On Apr. 22, 1972, the 1st Combat Aerial TOW Team, Vietnam (also known as "Hawk's Claw") was designated and deployed to Vietnam. The team's name reflected the first-time use of the airborne TOW missile system in combat against an armored enemy.

The "Hawk's Claw" team went into combat for the first time on May 2. Chief Warrant Officer (CWO) Carroll W. Lain made history on that morning when he fired a TOW missile which struck a tank. This was the first American-made guided missile to be fired in combat by a U.S. Soldier.

On Jun. 8, 1972, the 2d Combat Aerial TOW Team was formed after Gen. Creighton W. Abrams, Jr. decided to keep the XM26 aerial TOW in Vietnam as insurance against any future NVA armor penetration. The second team assumed the combat mission begun in May, while the first team returned to the United States.

The airborne TOW missile system proved to be very adaptable to combat operations, and the XM26 performed very well while in Vietnam. Hughes Aircraft Company technicians were able to handle the minor problems that occurred. Because the airborne TOW system was actually a test bed that had not been designed to be maintained in the field, it required the support of highly trained engineers and technicians as well as extensive laboratory test equipment to keep it operational. Despite the challenges, the airborne TOW achieved a 90 percent reliability rating for the entire period it was deployed in Vietnam. The lack of a limited visibility/night vision capability was the single largest impediment to XM26 system effectiveness during that time.

Between Apr. 30, 1972 and Jan. 11, 1973, the two HUEY gunships fired a total of 199 TOW missiles: 37 in training and 162 in combat. Of the missiles fired in combat, 151 (93 percent) were reliable and 124 (82 percent) scored hits on a variety of targets. These included: 27 tanks, 21 trucks, 5 armored personnel carriers, 3 artillery pieces, 1 antiaircraft gun, 1 122-mm rocket launcher, 5 machine guns, 2 57-mm guns, 5 caves, 8 bunkers, 2 bridges, 2 mortars, 2 ammunition storage dumps, 2 TOW jeeps (1 with launcher and 1 with missiles), and 1 house. There were 11 malfunctions and 4 misses. The latter occurred when the gunner fired the missile at a range in excess of 3,000 meters and lost it when the guidance wire ran out. Although the HUEYs encountered considerable machine gun fire, neither gunship was hit by enemy fire because they stayed high.

With the cease fire on Jan. 28, 1973, the mission of the 2d Combat Aerial TOW Team ended in Vietnam. The UH-1B HUEY helicopters and XM26 TOW systems were retrograded to the United States. With the success of the original airborne TOW team and the continued success of the replacement team trained in-country, funding for the next generation M65 TOW/Cobra was secured.