In late 1951, the French Air Force established the South Vietnamese 312th Special Mission Squadron at Tan Son Nhat Airfield equipped with Morane 500 Criquet liaison aircraft.

[3]: 10  In March 1952, a training school was set up at Nha Trang Air Base, and the following year two army co-operation squadrons began missions flying the Morane 500 Criquet.

[4]: 232  In meetings in Washington D.C. in May 1957, South Vietnamese premier Ngo Dinh Diem gave his reasons for deemphasizing the RVNAF, advising President Dwight D. Eisenhower and Secretary of State John Foster Dulles, "his main military requirement is ground forces.

However the Geneva Accords that ended the First Indochina War prohibited the introduction of jets into the country, so instead the F8Fs were replaced by ex United States Navy AD-6 Skyraiders with the first six arriving in September and a further 25 delivered by May 1961.

[3]: 54–5 In late 1960, in order to support the operations of the ARVN Rangers, the Military Assistance Advisory Group secured approval for the shipment of 11 H-34C Choctaws from the United States Army to replace the worn out H-19s of the 1st Helicopter Squadron.

As a final guarantee against bombing mistakes that might hurt the government's image, politically cleared and technically competent observers had to mark approved targets before air strikes could be launched against them - a rule of engagement reportedly directed by Diem.

Two officials from North American Aviation, the manufacturers of the T-28, visited Bien Hoa AB and reviewed these losses and advised that the T-28 wasn't designed for the stresses it was being subjected to as a close air support aircraft.

By the end of 1964, however, the combat sortie rate suffered as some key units were diverted from tactical operations and placed on "coup alert" during the seemingly endless political changes in Saigon.

The difficulties of that were noted by Seventh Air Force commander General Joseph Harold Moore who observed that, although several young field grade officers were showing promise as good leaders, "daily siestas and weekend slackening of effort is still a way of life."

Few officers possessed the linguistic and cultural skills needed for the job and advisor duty was frequently viewed as inferior and undesirable compared to a more glamorous and career-enhancing tour with the Seventh Air Force.

The US Army was training the H-34 pilots to fly the new UH-1s; and USAF units in the country taught Vietnamese airmen control tower operations, meteorology, armament maintenance and missile handling.

The planned liaison units, which included FACs, and the transport squadrons did not have enough aircraft, however, and MACV acknowledged that the proposed reconnaissance force, six RF–5s, could not cover an area the size of South Vietnam.

[11]: 315 On 8 June 1969, Presidents Richard Nixon and Nguyễn Văn Thiệu met on Midway Island and discussed both the withdrawal of US forces and the arming and training of South Vietnamese to take over a greater share of the fighting.

However desirable this might be as an ultimate goal, the Joint Chiefs of Staff did not believe that mere weapons could, in view of such problems as leadership and desertion, enable South Vietnam to take over major fighting responsibility against the current threat.

Thiệu's ambitious plan did, however, generate an additional $160 million in US military aid to improve logistics support and also produced a decision to speedup previously authorized recruiting, adding some 4,000 men to the RVNAF by June 1970.

In the tightly centralized US model, this agency functioned as command post for strikes throughout South Vietnam, establishing priorities among competing needs and issuing daily and weekly operations orders in support of the war on the ground.

US Defense Secretary Melvin Laird launched the Consolidated Improvement and Modernization Program which called for a South Vietnamese military establishment totaling 1.1 million in June 1973, with the RVNAF expanding to 46,998 officers and men.

During December 1970, however, the USAF advisory group became concerned that additional airmen, technicians, and medical professionals would be needed as South Vietnamese replaced US troops at air bases, logistics centers, command posts and hospital facilities.

Except for these fledgling pilots, the doctors and nurses, and the communications specialists trained for a time at Clark Air Base in the Philippines, policy called for transplanting courses of instruction to South Vietnam.

[10]: 273 The crash of the helicopter carrying ARVN General Đỗ Cao Trí and photojournalist François Sully on 23 February 1971 was attributed by US sources to mechanical failure and this led journalist Edward Behr to investigate the maintenance standards within the RVNAF.

FACs, who directed the actual strikes, seldom remained with a particular ground unit long enough to learn its special requirements, the characteristics of the operating area, or the patterns of enemy behavior.

Moreover, FACs received, at most, a smattering of night training, and some of them avoided daylight missions over heavily defended areas, on occasion falsifying reports or logs to conceal their dereliction of duty.

[10]: 299–301 From 1–7 December, RVNAF A–37s flew 49 sorties against PAVN transportation targets on the exit routes from the Ho Chi Minh Trail just inside the western border with Laos as part of Operation Commando Hunt VII, in preparation for taking over the interdiction campaign as early as the 1972–73 dry season.

From experience in North Vietnam and in the Easter Offensive it was obvious that high performance aircraft, backed up by Electronic countermeasures (ECM) and supporting forces, were necessary to penetrate and operate in such defenses.

The USAF Advisory Group, using teams of instructors dispatched from the United States, planned to teach a number of the South Vietnamese to take over the postwar training programs for the various types of aircraft, assisted as necessary by American civilians working under contract.

[12]: 60 By the time the cease-fire went into effect, the RVNAF had received the benefits of Project Enhance Plus, a final American push to strengthen the armed forces before the peace settlement restricted the flow of equipment to replacing, on a one-for-one basis, items already in the inventory.

The enemy trawlers and junks, for which the modified gunships would search, could carry the same antiaircraft guns and SA-7 missiles that earlier had driven the planes from vigorously defended portions of the Ho Chi Minh Trail.

Joyriding or careless taxiing, sometimes by drunken pilots, and failure to make preflight inspections cost the RVNAF, by Murray's reckoning, "the equivalent of an entire squadron of jet aircraft."

[19]: 386  On the morning of 3 April 1975 the RVNAF at Phan Rang launched a heliborne operation comprising more than 40 UH-1s and six CH-47s escorted by A-37s to rescue the remnants of the ARVN 2nd, 5th and 6th Airborne Battalions that had been cut off at the M'Đrăk Pass successfully evacuating over 800 soldiers.

At 07:00 the AC-119K "Tinh Long" flew by Lt. Trang van Thanh was firing on PAVN to the east of Tan Son Nhut when it was hit by a SA-7 missile, and fell in flames to the ground.