Boeing's F-15SE Silent Eagle has been selected as the only qualified bidder in South Korea's F-X Phase 3 competition for 60 fighters—but the country's air force is lobbying to overturn the decision in favor of the Lockheed Martin F-35 Joint Strike Fighter.

A win in South Korea would extend the F-15 production line into the next decade and launch an improved version that could compete for future fighter requirements in the 2020s. That outcome seems likely following the decision of the South Korean purchasing authority, the Defense Acquisition Program Agency (DAPA), to eliminate first the F-35 as too costly and then the Eurofighter Typhoon for a bidding irregularity—although EADS, representing the consortium in the South Korean deal, disputes DAPA's decision.

A cross-government committee chaired by Defense Minister Kim Kwan-jin will meet next month to rule on DAPA's decision. The review group will include air force officers, a member of the parliament's defense committee, an official from the finance ministry and the heads of DAPA and the Agency for Defense Development, which wants to lead indigenous industry in the development of its own stealthy fighter, the KF-X (AW&ST April 29, p. 46).

The finance ministry may back DAPA's fiscally conservative choice, but the air force has already shown its colors in fighting for the F-35.

“Some in the air force complain that the F-X Phase 3 is veering onto a wrong course, contrary to original aims,” the Yonhap news agency reported Aug. 20, a few days after DAPA's decision was disclosed. The “original aim,” as seen by the unnamed officers quoted by Yonhap, was evidently an F-35 order, and their attitude seems to be that the other two contenders were invited to bid just for the sake of creating competition.

This is a sensitive point. After competing for the F-X Phase 1 program, which the F-15 won in 2002, Dassault appears to have concluded that it had never had a chance and that the competition, for South Korea's benefit, was a waste of time and money in which its product was rejected in public. The French company said it had decided it could not work in South Korea and it would not take part in future competitions there. True to its word, it has not been a contender in either F-X Phase 2, also won by the F-15, or F-X Phase 3.

DAPA says that in F-X Phase 3 it excluded one contender—identified by local media as EADS—because the bidder, with the aim of reducing its price, changed previously agreed conditions of its offer without South Korea's consent. The contentious change was EADS's alteration of its offer from 45 single-seat and 15 two-seat Typhoons to 54 and six, respectively. EADS says there was no such agreement.

Lockheed Martin was excluded because its bid did not meet the budget, 8.3 trillion won ($7.4 billion), but has not given up, saying it “has not to date received an official notification from the Republic of Korea regarding the results of the price bidding for the F-X Program. The F-X source selection process has multiple phases, and we will continue to work closely with the U.S. government as they offer the F-35 to [South] Korea.”

If the South Korean government does not overturn the DAPA decision outright, an alternative would be to relaunch the competition. However, the aircraft that F-X Phase 3 is intended to replace—F-4 Phantoms and F-5 Tigers, delivered in the 1970s—are obsolete and close to the end of their service lives.

The F-15SE will not go into production without the South Korean order.Compared to its immediate predecessor, Saudi Arabia's F-15SA, it differs mainly in that it incorporates a suite of features to reduce its radar cross section (RCS), the most important being conformal weapons bays, accommodating either four AIM-120 missiles or two AIM-120s and two 1,000-lb.-class bombs, that replace the F-15's normal conformal fuel tanks (CFT).

Without F-X Phase 3, F-15 production may end in 2019—and earlier for long-lead items—when the last of 84 new-build F-15SAs is due to be delivered. F-X Phase 3 would prolong production until 2021, 49 years after the type's first flight.

Boeing's fighter has had several advantages in the program. Already in South Korean service, it has probably been the cheapest contender—a key advantage, since South Korea's parliament has forbidden DAPA to consider above-budget bids. Last month, DAPA rejected all offers because they exceeded the budget and called for new proposals from the competing companies.

Lockheed Martin not only had to deal with the high cost of the F-35; it also had to offer the aircraft through the U.S. government's foreign military sales (FMS) process, which stipulates that the price cannot be less than the U.S. military pays. Boeing could and did choose to offer the F-15SE as a direct commercial sale, with only weapons and some equipment being supplied through FMS channels.

Another advantage for the F-15 is that Korea Aerospace Industries is already a major subcontractor on the F-15, so it was easier for Boeing to meet DAPA's requirements for local content.

The F-15 almost certainly offered the best weapons capacity and range performance of the three aircraft, because of its size and CFTs. The Typhoon was also politically disadvantaged against competitors from the U.S., which underwrites South Korean security.

If South Korea's government sustains DAPA's decision, it will validate a Boeing strategy that looked quixotic in March 2009, when the Silent Eagle concept was unveiled. At that time, the F-35A was expected to be operational with the U.S. Air Force by 2013, with the sixth low-rate initial production batch being delivered. Contemporary U.S. budget documents predicted a flyaway cost for the F-35A of $70-75 million in South Korea's delivery years. Accordingly, the F-35 appeared very hard to beat.

Today, the F-35A is not expected to be operational with the U.S. Air Force until late 2016, and the service projects a flyaway cost of $96 million for 2020 deliveries. At the same time, Boeing's competitive position has improved with the 2012 Saudi order for the F-15SA, which not only restarts the production line, but funds (and makes less risky) three expensive features also used on the F-15SE: the all-digital flight control system, BAE Systems Digital Electronic Warfare System (DEWS) and redesigned cockpit with 11 X 19-in. flat-panel displays.

Although it is not formally a factor in South Korea's evaluation, the Saudi deal includes the local upgrading of the F-15S fighters to the SA standard; South Korea's F-15Ks could be similarly upgraded.

Boeing has evolved its fighter strategy since 2009. In particular, plans for development of the F-15 and F/A-18E/F Super Hornet have been more closely aligned. The F-15SA and SE cockpit displays use similar glass, processors and software, and Boeing is working on adding capabilities available on or in development for the F/A-18—for example, passive targeting (see page 20). The F-15K already has an infrared search-and-track system similar to that under development for the U.S. Navy's Super Hornets.

As part of the F-15SA program, the new fly-by-wire system and DEWS are in flight testing, while the new cockpit is in the advanced prototyping phase, undergoing integration testing in laboratory environments. Development of the conformal weapons bay is proceeding on schedule, Boeing says, following a 2010 flight demonstration. For most subsystems, requirements reviews are complete and design reviews are underway. Tests for features reducing the radar cross section are continuing.

Deliveries of Saudi Arabia's new aircraft are not due to begin until 2015, although Boeing has rolled out the first and is upgrading 70 F-15Ss to the F-15SA configuration. The company should be able to fill the Saudi order by building one a month, but the South Korean requirement—60 aircraft over four years—might demand more than doubling that rate. Deliveries of F-15Ks for South Korea and similar F-15SGs for Singapore ended in 2012. South Korea bought 61 F-15Ks under F-X Phases 1 and 2. One crashed.

After the F-15K won earlier F-X competitions with a mechanically scanning radar, Boeing sold the F-15SG to Singapore with the Raytheon active, electronically scanned array (AESA) APG-63(v)3 radar, which is the baseline offering for the F-15SE. Boeing says it told DAPA this year that an alternative is the Raytheon APG-82, selected by the U.S. Air Force to refit its F-15Es and due for entry into service in 2014. While the APG-63(v)3 uses a similar array to the F/A-18E/F's APG-79, the APG-82 uses the APG-79 processor and other components—another respect in which Boeing is pushing to make the F-15 and F/A-18 more common.

The impact on the F-35 program of an F-15SE win would be more psychological—being the first competitive loss for Joint Strike Fighter—than material, for the time being. The F-35 team has won in Japan and appears to be headed for a non-competitive selection in Singapore. Firming up commitments in Australia, Canada and Europe and completing development of the aircraft are of greater strategic importance.