Because the AA-2 was the primary weapon of the MiG-21, ‘Atoll’ became the first air-to-air missile in service with dozens of other air forces, too.
I recalled the following story while working on the book ‘Hunt for the U-2’ these days (one of coming titles for the Europe@War series published by Helion & Company) .i.e. this is from memory, so don’t kill me if I missed a point or two…
After successfully assaulting several islands held by Chinese Nationalists, in period 1955-1957, in summer 1958 the People’s Liberation Army of China (PLA) set in motion preparations to assault the islands of Quemoy and Matsu, held by the so-called Nationalist Chinese – a US-supported government that fled from mainland China to the island of Formosa, later Taiwan (that happened already in 1950).
The obvious first task was to secure air superiority, to isolate the local Nationalist garrison, then subject it to intense bombardment, and thus enable a successful amphibious assault. Correspondingly, the People’s Liberation Army Air Force (PLAAF) began deploying its brand-new MiG-17F fighter-bombers in the skies over Quemoy.
The Chinese Nationalist Air Force – or the Republic of China Air Force (CNAF/ROCAF) – was already on alert: after all, it was in a near-constant combat contact with the PLA/PLAAF already since 1950s. Its North American F-86F Sabre interceptors were soon flying up to 100 combat sorties a day; RF-84Fs flew intensive recce sorties over mainland China, too. Moreover, the appearance of MiG-17Fs alerted the USA, Nationalist Chinese primary ally – and that to a degree where the US Air Force deployed a squadron each of Lockheed F-104A Starfighters and North American F-100D Super Sabres, and a wing of F-101C Voodo interceptors to Taiwan. The US Marine Corps followed by deploying its F4D-1 Skyray interceptors, while the CIA added three RB-57Ds (flown by Taiwanese pilots), which were to conduct high-altitude reconnaissance sorties over the People’s Republic of China (PRC).

The situation culminated in the so-called Taiwan Crisis. A series of fierce air combats raged high in the skies over the Fujian province from late July through August well into September 1958. Mid through this, two pilots and five NCOs from the US Marine Corps squadron VMF-323 were sent to Taiwan together with 40 of the then brand-new GAR-9 air-to-air missiles. In conditions of utmost secrecy, they helped install these on about a dozen of CNAF/ROCAF’s F-86Fs, then a captain from the USAF explained the Taiwanese how to deploy missiles against MiGs flying at 40,000ft (or higher).
On Sep. 24, 1958, the Taiwanese clashed with PLAAF fighters, and claimed nine ‘confirmed’ and two ‘probable’ kills, plus one MiG damaged, in exchange for one ow n loss. Either three or four of PLAAF’s MiGs should’ve been shot down by these brand-new, US-made air-to-air missiles, which subsequently became known as AIM-9B Sidewinder. This was the first time ever that guided air-to-air missiles were used in combat.
Overall, during the Taiwan Crisis, the PLAAF deployed 691 combat aircraft within the combat zone, and they flew 3,778 sorties. The PLAAF reported a total of 13 air combats, and to have shot down 14 Taiwanese jets, while losing 5. The CNAF/ROCAF claimed to have shot down 31 or 32 PLAAF aircraft, in exchange for 3 own: it fired a total of 6 Sidewinders, four of which have scored hits.
BTW, one of Sidewinders that has hit its target has failed to detonate. It was found embedded inside the fuselage of a PLAAF MiG-17F. The Chinese promptly rushed it to the Soviets, who in turn reverse-engineered every single piece of wire, bolt and screw (yes, Soviet missile designers admitted this, later on). Thus came into being the R-3S (ASCC/NATO-codename ‘AA-2 Atoll’) – perhaps the most-widely deployed air-to-air missile in the Soviet service. Moreover, because the R-3S was the primary weapon of the MiG-21, ‘Atoll’ became the first air-to-air missile in service with dozens of other air forces, too.

Photo credit: U.S. Air Force, Varga Attila via Wikipedia