The first United States Air Force personnel assigned to South Vietnam arrived in August 1950, when the United States established a Military Assistance Advisory Group (MAAG), with headquarters in Saigon. To enable military supplies and equipment to be transferred, the US signed a Mutual Defense Assistance Agreement on 23 December 1950 with France, Vietnam, Cambodia and Laos. Indochina, being a French colony at the time meant that American aid went first to the French forces in Vietnam, with limited aid to the Vietnamese auxiliary units in existence. Subsequently much of the military aid, mostly C-47 transports went to reinforce French Air Force units.
Other aircraft supplied to the French in Indochina in 1950/51 were Douglas B-26 Invaders, Bell P-63 Kingcobas, former U S Navy Grumman F6F Hellcats, Grumman F8F-1B Bearcats and Vought F4U Corsairs.
With the withdrawal of the French in 1955, the South Vietnamese Air Force came into existence and inherited much of the former French aircraft. American support continued though the 1950s, with additional B-26s, Douglas A-1 Skyraiders and North American T-28 Trojans for pilot training.
Late in 1961 the U.S. began sending USAF and U.S. Army personnel to South Vietnam to train and advise its personnel. U.S. personnel were not to engage in combat operations, but sometimes did. Known as the National Front for the Liberation of South Vietnam or the Viet Cong, the guerrillas shot down four U.S. Army helicopters. As the Viet Cong became more active and as more Americans became casualties, the U.S. stepped up the training and the supply of equipment. The goal was it could finish training as soon as possible and withdraw.
In South Vietnam, the Viet Cong usually operated at night, and as a response, the USAF developed night tactics using SC-47s to drop flares. Early in 1962 tests began for defoliating the jungle to deny the enemy cover. As Viet Cong activity increased, so did the response and U.S. personnel were given permission to engage the enemy under certain conditions.
Much of the U.S. buildup consisted of Army and Marine helicopter units to increase support to South Vietnamese troops in the field. However, U.S. strategy still called for the buildup of South Vietnamese units to the point where they could handle their own battles, with the U.S. to remove its forces as soon as possible
In what is now referred to as the Gulf of Tonkin Incident, North Vietnam carried out its first overt hostile action specifically against the U.S. on 2 August 1964 when three of its Soviet-built torpedo boats attacked the USS Maddox 28 miles off the North Vietnamese coast. Two nights later, other attacks (now known not to have occurred) were reported against the USS C. Turner Joy.
In response, President Lyndon B. Johnson ordered the U.S. Navy to send planes on a bombing mission against the torpedo boat bases and an oil storage depot. On 7 August, Congress adopted the Gulf of Tonkin Resolution giving President Johnson authority to use all measures, including armed forces, to assist South Vietnam.
It was then that the USAF sent jet aircraft into South Vietnam for the first time.
The tempo of the conflict increased in 1965. The Viet Cong intensified its guerrilla activity and began direct attacks on U.S. forces in South Vietnam. When the VC scored some impressive victories over South Vietnamese troops, the U.S. increased its forces even more. Officials in Washington D.C. no longer spoke of withdrawing U.S. personnel; rather, they talked of additional U.S. forces for South Vietnam and the president generally approved their recommendations.
On 2 March 1965, the USAF instituted its famous "Rolling Thunder" campaign, the systematic bombing of North Vietnam, starting at the Demilitarized Zone (DMZ) between North and South Vietnam. Its planes flew from bases in South Vietnam and Thailand. By slowly advancing the target areas northward across North Vietnam, it was hoped the North Vietnamese leaders would eventually be convinced to sit down at the peace table. However, Washington imposed stringent controls upon these operations, lest Red China or the Soviet union actively enter the conflict.
On 23 July 1965, the U.S. lost its first plane to a Soviet-built SAM missile. SAM (Surface-to-Air Missile) sites were first detected in North Vietnam on Apr. 5, 1965. The next month a U.S. Navy plane was lost to a SAM and the U.S. began a series of special missions named "Iron Hand" against the rapidly expanding missile sites. Most were near the Hanoi-Haiphong area, but Washington had exempted these from air attack, fearing large civilian casualties. However, sites in other areas were fair game. By the end of the year, 56 SAM sites had been located by U.S. reconnaissance aircraft.
During the last half of 1965, Viet Cong activity inside South Vietnam continued to increase. Several large scale attacks were launched against U.S. and South Vietnamese positions and in each instance, airpower was used to thwart the enemy efforts. Still, the Viet Cong retained its ability to move from place to place at night, almost at will, and sever any line of communication it desired.
By 1966, U.S. strength had grown to 385,000 personnel, bolstered by additional forces from South Korea, Thailand, the Philippines, Australia, and New Zealand. Viet Cong successes were greatly diminished and their only significant victory was in March when their forces overran a Special Forces camp in the A Shau Valley. Because of heavy Viet Cong losses during the year, it was estimated that North Vietnam had to commit more than 58,000 of its regular troops to assume a greater share of the conflict.
On 24 December 1965, President Johnson declared a bombing halt over North Vietnam to try to persuade Hanoi to discuss a political settlement. It lasted until 30 January. This halt followed one of six days the preceding May. Hanoi responded to neither, but used the time to rebuild its strength, repair previous damage, and send more troops and supplies southward. So, Rolling Thunder began again and U.S. aircrews not only had to attack the new targets, but also those they had already destroyed which had been rebuilt or repaired.
In February, the Soviet Union and the United Kingdom attempted to get a peace dialog going between the United States and North Vietnam, but were unable to do so since Johnson had resumed the air strikes. Acting against the advice of the Pentagon, the Johnson Administration chose not to escalate the Rolling Thunder attacks under the belief that the Communist Chinese and North Vietnamese would charge that the pause over Tet was just a prelude to more drastic actions.
On 3 September 1966, North Vietnam sent up its MiG-21s in force for the first time from five air bases which had not previously been attacked because they had been hidden in underground bases. By the end of the year, Rolling Thunder had progressed northward, reaching the Hanoi area, and the B-52 Arc Light missions started over North Vietnam.
U.S. strength in the South Vietnam war zone grew to 486,000 personnel in 1967. A new plan was instituted - South Vietnamese troops were to pacify the countryside, while U.S. and Allied forces were to battle Viet Cong and North Vietnamese troops. The plan scored several major successes and by the end of the year the not a single engagement had been won by the Viet Cong. The guerrillas, however, retained great tactical flexibility. North Vietnam then decided to build-up its forces in Cambodia and Laos.
Early in 1967, Washington approved "Rolling Thunder" targets even closer to Hanoi. North Vietnam reacted by throwing almost 100 MiGs into the air to turn back the USAF attacks. USAF and Navy aircraft losses began to mount and in April, Washington finally approved attacks on four of the five MiG airfields as part of Operation Bolo, whose purpose was to destroy the North Vietnamese Air Force. By the end of 1967, the year’s score was 75 MiGs downed at a cost of 25 U.S. aircraft in air-to-air combat.
In the United States the antiwar movement began to pick up steam. Servicemen were being seen as amenable participants in the slaughter of innocent people in Vietnam. Some Vietnam Veterans began speaking out against America's role in Southeast Asia. Rifts were developing between the military and the vocal opponents of the war.
1968 was the midpoint of the Vietnam War. The American public was well-informed about the ground war in South Vietnam, but the air was in Laos, North Vietnam and soon Cambodia was still in the background.
Late in January 1968, the Communists launched their famous Tet Offensive throughout South Vietnam. They hoped to spark a national uprising. The Viet Cong attacked throughout the country, striking numerous installations, cities and airfields simultaneously. Initially, the enemy made some gains but under a withering assault from both air and ground, the offensive failed by late February.
However, the Tet Offensive had a devastating effect upon the U.S. Many people at home, watching the nightly TV news, were appalled and confused by the carnage they saw. Some even believed the Communists had won and the U.S. had lost. As a consequence, the U.S. sent even more troops to South Vietnam in an attempt to accelerate the time when responsibility for the war could be turned over to South Vietnam and the U.S. could withdraw its forces.
The Tet Offensive damaged the presidency of Lyndon B. Johnson beyond repair. He announced that he would not run for re-election. It also highlighted a growing credibility gap and increasing public skepticism about the outcome of the war.
On 31 March, President Johnson ordered a bombing halt north of the 20th parallel. He hoped once again to induce North Vietnam’s leaders to return to the peace table. Although Hanoi agreed to begin discussions, it continued to pour 22,000 troops into South Vietnam every month. So the U.S. doubled its air operations south of the 20th parallel, concentrating on enemy troops and supplies crossing the DMZ.
After several months of discussions at Paris, on 31 October President Johnson ordered a complete halt of all air, naval, and military artillery bombardment of North Vietnam and the "Rolling Thunder" campaign came to an end.
America's entire political and military establishment was under harsh criticism on all fronts by the end of the year for being unable to produce a victory against a poor third-world country like North Vietnam. The prevailing mood in the United States at the time of the November presidential election was to get out now and cut our losses while we can.
Shortly after President Richard Nixon took office in January 1969, the "Vietnamization" program was accelerated. Vietnamization was the training and equipping of South Vietnamese forces to fight their own war so the U.S. could withdraw its forces as had been planned since 1962. The first U.S. troops departed in July and by the end of the year, 69,000 had been withdrawn. President Nixon ordered the bombing resumed.
During the rainy season which began in May, North Vietnam began stockpiling supplies and equipment inside its border with Laos, and it built an oil pipeline into the Laotian panhandle. These supplies were shipped to North Vietnam either by rail from China or by sea from China or the Soviet Union through its ocean ports, primarily Haiphong.
In 1970 the North Vietnamese changed their strategy. They built up modern, conventional forces as the Viet Cong guerrilla forces they had previously relied on to fight in the south had been decimated over the past two years. Also there was decreased support from villagers who resettled in refugee camps rather than risk being bombed by the USAF for having Viet Cong in them. Also Phoenix Program actions by the Central Intelligence Agency to kill communist insurgents was becoming more and more successful.
As the South Vietnamese Air Force (VNAF) capability was expanded, the first USAF units were withdrawn. Inside South Vietnam, enemy activity was at a low during the year. Even then, the USAF flew more than 48,000 sorties, flying strike missions against North Vietnamese forces that had infiltrated into South Vietnam.
In response, North Vietnam chose to emphasize technical development and modernize its armed forces. Officials in Hanoi realized that this would be necessary to counteract the improvements in the armed forces of South Vietnam. Conventional forces could also capture and hold more real estate than the guerrilla units.
North Vietnamese and Viet Cong troops had long operated along the Cambodian border with South Vietnam. President Nixon ordered Operation Menu, the secret bombing of Cambodia. The bombing lasted for 14 months. More bombs were dropped on Cambodia than the total dropped by the Allies during World War II. This violated Cambodia's neutrality. On 1 May U.S. and South Vietnamese troops crossed the border and struck the enemy’s sanctuaries. They withdrew into South Vietnam by the end of June.
The invasion of Cambodia sparked large anti-war demonstrations. Four students were killed by National Guardsmens at Kent State University.
The bombing of Cambodia and the subsequent invasion, destabilized the country. Support for the Khmer Rouge increased after a U.S. backed military coup by Lon Nol. The Khmer Rouge made substantial territorial gains.
The U.S. withdrawal from South Vietnam continued during 1971 and by December the USAF was down to 277 fighter and strike aircraft and 28,791 personnel from a 1968 high of 737 aircraft and 54,434 personnel. The VNAF was now responsible for 70% of all air combat operations. Enemy guerrilla activity continued to be sporadic.
From February through September, USAF fighter-bombers attacked SAM sites, enemy road construction through the DMZ, and oil-storage facilities. Most of these missions were into southern North Vietnam, leaving Hanoi to continue its build-up in the north.
By October the North Vietnamese AF had about 250 MiGs which had become a significant threat to U.S. flyers. As a result, Washington authorized the USAF and Navy to bomb the three MiG airfields in southern North Vietnam and on November 7-8, the U.S. "neutralized" these three bases with Operation Proud Deep. It was the most extensive air campaign within North Vietnam in three years.
Khmer Rouge activity continued within Cambodia and eventually the road from the capital, Phnom Penh, to its seaport, Kompong Som was cut. Supplies then had to be flown in or carried on ships up the Mekong River from South Vietnam. USAF and U.S. Army aircraft provided aerial escort to river convoys and aerial support to ground operations of the Cambodian Army which nevertheless suffered repeated setbacks.
In January captured North Vietnamese documents revealed a plan for a large offensive in mid-February, during the Tet holiday on the 17th, and President Nixon's visit to the People's Republic of China. The Pentagon and officials from PACAF and MACV formulated responses to the planned invasion, which included the use of Tactical Air and naval gunfire, the deployment of additional carriers, rapid troop augmentation via tactical airlift and more Arc Light missions.
In February USAF and VNAF aircraft conducted concentrated preemptive strikes against North Vietnamese positions, attempting to thwart the anticipated invasion. On 30 March, the North Vietnamese launched a large, three-pronged invasion of South Vietnam, using tanks and mobile armored units. The biggest battle was at An Loc where, by the end of June, the North Vietnamese had lost most of its tanks and artillery.
The offensive was halted mainly due to the intervention of US airpower. It demonstrated how reliant South Vietnam had became on American air support.
During the year, Cambodian forces were able to win localized victories against the Kmer Rouge. On the other hand, the Khmer Rouge were unable to capture their primary target, the capital, Phnom Penh. During these ground operations, U.S. airpower, including B-52s, continued to hammer the enemy, but there was a limit to what air power could accomplish.
Because of the North Vietnamese offensive, President Nixon on 8 May suspended peace talks and ordered Operation Linebacker, the renewed bombing of North Vietnam and the aerial mining of its harbors and rivers. When North Vietnam appeared ready to talk peace in October, yet another bombing halt was directed. North Vietnam then balked for two months over some of the cease-fire provisions, so President Nixon ordered on 18 December 1972 the heaviest bombing of the war against Hanoi and Haiphong, Operation Linebacker II.
For 11 days, the USAF pounded every possible military and transportation target with B-52s and tactical fighters. This brought a North Vietnamese agreement on 29 December to return to the peace table.
After North Vietnam agreed on 29 December 1972 to return to the peace table in Paris, the U.S. restricted its air attacks on North Vietnam to the area south of the 20th parallel. On 15 January 1973, the U.S. announced an end of all mining, bombing, and other offensive operations against North Vietnam.
A nine-point cease-fire agreement was signed in Paris on 23 January 1973, to become effective on 28 January. It called for the U.S. to remove all of its forces from South Vietnam and for all POWs to be returned within 60 days.