South Korea’s Large New F-35 Purchases Are Vital For America’s Pacific Strategy: But Are the Fighters Reliable?

The U.S. State Department informed Congress in September 13 that it had approved the sale of 25 F-35 fighters with associated spare engines and equipment to South Korea. The department reported that the sale would “improve the Republic of Korea’s capability to meet current and future threats by providing credible defence capability to deter aggression in the region and ensure interoperability with U.S. forces,” adding that “the proposed sale of this equipment and support will not alter the basic military balance in the region.” Valued at $5.06 billion, the sale is expected to expand the Korean F-35 fleet from its current strength of 60 ordered aircraft to 85, making it one of the world’s largest operators of the class behind only Japan and the United States itself. Three squadrons’ worth of F-35s were previously acquired to phase out South Korea’s three units of Vietnam War era F-4E Phantoms, with the fourth squadron potentially phasing out its similarly old F-5E/Fs or possibly older units of F-16s. South Korea’s fighter fleet is considered the most capable among U.S. aligned states, although the performance of the F-35 has been put to question within the country. Inspections found the fighters suffered from 234 flaws over 18 months from January 2021 to June 2022, including 172 “non-flying status” (G-NORS) and 62 “cannot perform specific mission status” (F-NORS) cases – with 117 flightless and 45 mission-specific failures in 2021 and little improvement into 2022. The specific mission failure rates are notably more than twice those of South Korea’s F-4 and F-5 fighters.

Regarding the effectiveness of the F-35 Shin Won Min, a member of the South Korean National Assembly’s National Defence Committee, warned: “the F-35A was introduced with a very large budget to solve the issue of obsolete fighter jets and strengthen combat effectiveness against North Korea. In the case of the escalation of North Korea’s nuclear and missile threats, it cannot be permitted that this core combat force cannot function properly.” Performance issues have taken Korean F-35s out of service for periods ranging from a few days to several months, and add to existing questions regarding the aircraft’s viability in a wartime situation. Examples include an immediate cancellation of flights after an inspection in June 2022 revealed issues with avionics, and the sending of an F-35 to maintenance due to abnormalities in its fire controls the previous month. In January that year a Korean F-35 was forced to make a “belly landing” after its landing gear refused to open, damaging the aircraft, with these being only a few of the recent cases. A South Korean military official accordingly reported anonymously to local media: “although there may be an abnormality in a certain model or a component problem, the F-35A’s situation is particularly serious.” Issues faced by the South Korean fleet mirror those seen across much of the world among F-35 operators. 

Despite wide ranging issues, the F-35 remains the only fifth generation fighter in production in the Western world, and thus compatible with a NATO standard military, which makes it the only fighter capable of seriously challenging China’s own fast growing fifth generation fighter fleet. Although the F-35 is a relatively light single engine fighter, and this lacks the endurance, firepower, radar size or flight performance of the Chinese J-20, it is considered broadly on par in terms of its avionics and stealth capabilities. Proliferating F-35s to its security partners operating in the Pacific is considered key to American efforts to sustain a favourable balance of power in the region, with China being the only country outside the Western sphere of influence to field full squadrons of fifth generation fighters and thus lacking coalition partners capable of operations at the same level. Indeed, the head of the Pacific Air Forces Kenneth Wilsbach in the second week of September stressed: “Interoperability with [U.S.] allies and partners… the way we train, especially with [our] Korean allies and partners,” as key to America’s ability to tackle China’s J-20 fleet specifically. While South Korea under the previous Park Geun Hye and Moon Jae In administrations appeared to hedge its position between Beijing and Washington, under the new Yoon Suk Yeol administration which took power in May 2022 the country has closely aligned itself with the United States against its neighbour. The success of American efforts, however, will depend heavily on how quickly issues with the F-35 can be resolved, with the fighter suffering from approximately 800 performance defects which have on multiple occasions caused crashes – and more often impeded effective operations.