"Korea is faced with a vast array of growing threats, both in the air and on the ground" - Lockheed Martin

South Korea is surrounded. To the south, east and west lie the sea. To the north lies its arch-rival North Korea. While the region south of Seoul is full of industrial and residential development, the 50km (31-mile) stretch to the demilitarised zone that has divided Korea since 1953 is barely developed, only rolling hills and forest under blue skies.

"Property gets cheaper the further north you go," jokes one South Korean. The DMZ itself resembles a lush nature reserve - provided one ignores the long stretches of barbed wire and dour soldiers in lookout towers.

South Koreans live with the very real possibility they could find themselves in a major war with the neighbours. In a conflict with North Korea, the Republic of Korea Air Force (ROKAF) would be called upon to hammer a vast range of targets north of the DMZ - such as thousands of artillery tubes in hardened bunkers in range of Seoul, and missile launch sites deep in North Korea.

Seoul is unlikely to fight alone. The USA has almost 30,000 personnel on the peninsula, with a significant USAF combat presence. Japan could also be drawn in. The US military has war-gamed a horrifying scenario in which an embattled North Korea launches a nuclear weapon which strikes Tokyo.

 PAK FA

 The PAK FA is not rated as a contender

Copyright: Vladislav Perminov

Given this security backdrop, Seoul places a high priority on the modernisation of the ROKAF. A major element of this is the F-X III competition to replace more than 60 McDonnell Douglas F-4E Phantoms.

A request for proposals for more than 60 aircraft is expected in February. The shortlist is diverse - Boeing F-15 Silent Eagle, Lockheed Martin F-35 Lightning II, Eurofighter Typhoon and Sukhoi PAK FA (also known as the T-50). Deliveries of the winning aircraft are likely to start in 2016.

There is no question the F-4Es need to be replaced. The USAF has not operated the type for nearly two decades, and the ROKAF's Phantoms lack the precision weapons, sensors and communications equipment found on more advanced ROKAF types, such the F-15K Slam Eagle and KF-16. Delivered in the 1970s, the Phantoms' airframes are also nearing the end of their service life. One industry source said the ROKAF is already standing down some of the ageing aircraft, resulting in a capability gap.

Heart and seoul
Although there are four fighters on the F-X III shortlist, the real battle is only between two - the F-15SE and F-35. This is mainly down to the deep US-Seoul relationship. Visitors to the US army's vast Yongsan army base in the heart of Seoul find themselves in small-town USA, complete with high school, fast-food restaurants and administration buildings where US and Korean military personnel work side by side. Seoul's Defense Acquisition Program Administration, the ultimate arbiter of F-X III, lies a short walk away, just outside the walls of the base.

"FX-III is the USA's to lose," said Richard Aboulafia, an analyst for the Teal Group. "It's more than just the political dimension of a strategic relationship, which in itself is all-important to a country with a volatile and violent neighbour. It's also about shared logistics, training and doctrine."

He cited a number of advantages for the F-15SE. "It's got commonality with South Korea's existing fleet, a degree of stealth for the opening stages of a conflict and plenty of payload, which is important given the nature of the threat. Its only drawback is that it doesn't have all the qualities associated with the F-35." He added that the F-35 offers a close relationship with the USAF for years to come, "and the world's most modern air combat system [excepting the F-22]". He noted, however, that the F-35 cannot match the F-15SE on payload. "The only other problems with the F-35 concern uncertainties about cost, timing and industrial benefits," he said. "I'd give the two US planes an equal chance."

 F-15SE

Boeing's pitch focuses on the F-15SE's payload

Credit: Boeing

Boeing lauds the F-15SE's payload, which it claims is the highest in the competition, as well as a unique "stealthy-when-needed" feature. In the early stages of the conflict, when stealth is useful for countering enemy air defences - given the decrepit state of the North's air force, the air-to-air mission does not seem to concern contestants - the F-15SE would operate with conformal weapons bays that help reduce the aircraft's radar cross-section.

Following the attainment of aerial supremacy, stealth would no longer be a major requirement, said Boeing. It would take three hours to trade the F-15SE's weapons bays for conformal fuel tanks, creating what Boeing refers to as an F-15K+ configuration, which is optimised for heavy loads of precision weapons. Boeing claimed this heavy configuration is ideal to efficiently destroy hardened targets in North Korea. The canted tails of the F-15SE allow for two additional weapons stations on the F-15SE's wings as compared with previous versions of the fighter.

"The F-15SE offers Korea the flexibility to field an aircraft with both reduced radar cross-section capability and a heavy combat payload," said Howard Berry, Boeing's F-X III campaign manager.

"We do this by offering the conformal weapons bay for selected mission profiles, and the ability to convert into a heavier configuration for a variety of missions."

Platform compatibility
In November 2010, Boeing announced Korean Aerospace Industries (KAI) would design, develop and manufacture the Silent Eagle's CWB. In addition, the F-15 is a known quantity to the ROKAF - the F-15K Slam Eagle won both Korea's F-X I (40 aircraft) and F-X II (21 aircraft) competitions. The final eight F-15Ks of the F-X II order will be delivered by April 2012.

The F-15K is likely to be in ROKAF service for decades. Boeing said the F-15SE will have 85% platform compatibility with the F-15K, simplifying logistics and training. For its part, Lockheed Martin pushes the F-35's all-aspect stealth. "Korea is faced with a vast array of growing threats, both in the air and on the ground," said Lockheed. "The very low observable F-35 is designed from the ground up to defeat these threats and the threats that will emerge to threaten Korea over the next 30 to 40 years."

Lockheed Martin also stressed the economies of scale inherent in a programme that will "deliver thousands of F-35s over the next 30 years" - an excellent sensor suite and full interoperability with US forces.

Both companies are also committed to Korean industrial participation, with decades of experience. KAI produced the KF-16 fighter under licence and also produces the forward fuselage of the F-15. Samsung Techwin produces the F-15K's General Electric F110 engine and KF-16's F100. Several other subsystems for both the F-15K and KF-16 are also produced in Korea.

It would be informative to compare precise differences between the radar cross-sections of the F-15SE, with its conformal weapons bays, and the F-35. The highly sensitive nature of the technologies, however, prevents both companies revealing details. What is certain is that the F-35's primary attribute, stealth, would be compromised when weapons are mounted externally.

F-35 

The F-35 Lightning II is on Seoul's F-X III contest shortlist to replace its F-4E Phantoms

Copyright: Lockheed Martin

Industry observers are more dubious about the chances of the other two aircraft in the competition - the Eurofighter Typhoon and PAK FA. The Eurofighter, eliminated from the original F-X I competition, is regarded as a superb dogfighter. In the recent air war over Libya it demonstrated its attack capabilities. On the other hand, the ROKAF's large stocks of American weapons would need to be integrated with the platform, and the aircraft is not known for its stealth qualities.

If the Eurofighter is a dark horse, the developmental PAK FA has little realistic chance of winning the competition. Aboulafia summed up the prevailing view of the Russian fighter: "PAK-FA offers a unique combination of more risk than F-35, with less effectiveness, no interoperability, no strategic relationship, and a dubious logistics situation. It has no chance."

It is hard to understate the importance of Seoul's F-X III competition to the two main contestants, Boeing and Lockheed Martin.

For Boeing, it represents an opportunity to add another chapter to the long success story of the F-15.

For Lockheed Martin, F-X III would provided a badly needed boost to the troubled, but still promising, F-35 programme. The blue skies of the DMZ await.

Source: Flight International