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South Korean Defense Sources Express Concerns About Unreliable F-35 Fighters

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South Korean Defense Sources Express Concerns About Unreliable F-35 Fighters

The worries echo a litany of complaints made by U.S. military officials about the fifth-generation fighter.

South Korean Defense Sources Express Concerns About Unreliable F-35 Fighters

An F-35A in service with the ROK Air Force.

Credit: Lockheed Martin

The Republic of Korea Air Force (RoKAF), the official name of South Korea’s air force, has faced significant difficulties with its two new squadrons of Lockheed Martin F-35 stealth fighters, 40 of which have been delivered to meet an order placed in 2014 with 20 more currently on order to form a third squadron.

According to air force data obtained by Shin Won-min, a member of the South Korean National Assembly’s National Defense Committee, inspections have found the F-35s suffered from 234 flaws over 18 months from January 2021 to June 2022. These included 172 “non-flying status” (G-NORS) and 62 “cannot perform specific mission status” (F-NORS) cases. The data recorded 117 flightless and 45 mission-specific failures in 2021, and there was little improvement in the first half of 2022, with 55 and 17 failures of these types occurring over six months. The specific mission failure rates are notably more than twice those of South Korea’s Vietnam War era F-4 and F-5 fighters, the former of which is being directly replaced by the F-35.

Regarding the implications of these issues, Shin 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.”

An inspection in June, which revealed issues with avionics and forced an immediate cancellation of flights, came a month after an F-35 was sent to maintenance due to abnormalities in its fire controls. That in turn followed a “belly landing” in January after a fighter’s landing gear refused to open. These were only a few of several recent cases. Such issues have taken South Korea’s F-35s out of service for periods ranging from a few days to several months, and add to existing questions regarding how viable the aircraft would be in a wartime situation when high reliability is vital.

“Although there may be an abnormality in a certain model or a component problem, the F-35A’s situation is particularly serious,” a South Korean military official reported anonymously to local media. An Air Force source commented that it “must take time” before the process of operating and repairing the new fighter class becomes smoother.

The F-35 is the only Western post-fourth-generation fighter in production. Having been developed under the Joint Strike Fighter program it is optimized for strike and air defense suppression missions, making it potentially ideal for tackling North Korea’s extremely dense and fast-modernizing surface-to-air missile network. The F-35 is effectively South Korea’s only option to ensure technological parity both with neighboring Japan, which is set to become the largest F-35 operator other than the U.S. military, as well as with China, which developed a similarly advanced fifth-generation fighter under the J-20 program and has a second, the FC-31, set to enter service shortly.

Having been developed under the largest weapons program in history, with the cost estimated at over $1.6 trillion, the F-35 has been widely described as “too big to fail” despite the considerable issues that have frequently been raised with its performance by both civilian and military officials.

These issues are far from isolated to South Korea. In April 2021, the U.S. Air Force’s deputy chief of staff for strategy, integration, and requirements, Lt. Gen. Clint Hinote, warned that the current version of the F-35 was highly unlikely to be able to make contributions to future high-end conflicts due to the fighter’s wide-ranging performance issues.

“It wouldn’t be worth it… every [F-35] fighter that rolls off the line today is a fighter that we wouldn’t even bother putting into these scenarios,” he noted. His assessment supported those recently made in South Korea, and Hinote is not the only one to raise such concerns in the United States, either.

U.S. Marine Corps Captain Dan Grazier highlighted “a host of alarming problems” and “the F-35’s lack of progress in nearly every essential area” to bring it closer to a combat ready state. These issues included continued malfunctions for “most combat-crucial computer systems,” major cybersecurity vulnerabilities, and “so many cracks” requiring “so many repairs and modifications” that it made operating the aircraft far from practical.

In late 2020, acting U.S. Secretary of Defense Christopher Miller had referred to the F-35 as “a piece of…”  and to the program as a “monster” created by the Pentagon. More recently, following several dismal reports by the Government Accountability Office on the fighter’s performance, a nearly two-hour hearing on Capitol Hill highlighted its engine issues as a particularly problematic feature.

“You give us an engine and it doesn’t work, well it worked for a little while until it gets some dust around and then it doesn’t work. What the hell? What’s going on here?” House Armed Service Subcommittee on Readiness Chairman Congressman John Garamendi stated at the hearing, which found that engine issues were causing unavailability rates at 600 percent of standard levels for the Air Force.

Such harsh criticisms date back to late Senator John McCain’s tenure as Chairman of the Senate Armed Services Committee, when among multiple criticisms he stressed that “the F-35 program’s record of performance has been both a scandal and a tragedy with respect to cost, schedule, and performance.”

Sixteen years after its first flight, the number of factory flaws reported has remained relatively consistent, with new flaws continuing to be discovered as old ones are slowly fixed, leaving the figure at approximately 800 as of late 2022.

While there are hopes that the F-35 will improve with time, the rate at which deficiencies have been addressed means it will likely be many more years until it is ready for high intensity operations against a near-peer adversary. The U.S. Air Force has meanwhile indicated it is considering simpler alternatives to allow it to cut planned acquisitions considerably.

The fighter has nevertheless remained popular on export markets for a number of reasons, including the unique intelligence that being part of an F-35 network can provide since all stealth fighters worldwide are interlinked. Also attractive are the fighter’s potential should it be made to work, its relatively low cost, and the absence of any other NATO-compatible fighter from its generation.

For South Korea, unlike other F-35 clients, the country’s development of an indigenous fifth generation fighter under the KF-21 program provides it with more options to diversify its fleet without returning to placing orders for fourth-generation aircraft. The KF-21, which first flew in July and will enter service before 2030, is expected to be acquired in over twice the numbers of the F-35, forming at least six squadrons.

This contrasts to the U.S. Air Force, which, for a number of reasons including denying Lockheed Martin a monopoly, reverted to acquiring fourth-generation fighters in 2020. The U.S. Air Force ordered F-15EX jets, which, although more expensive and less stealthy than the F-35, are at least much more reliable and fully ready for high intensity combat.