SEOUL, South Korea — South Korean defense officials are in a quandary over how to acquire an active electronically scanned array (AESA) radar, a key component for the country's fighter development program code-named KF-X, following the US refusal to transfer the advanced radar technology.

South Korea had expected  to it would be able to learn the AESA technology for the KF-X jet through offset deals connected to its F-X III contract to buy 40 Lockheed Martin-built F-35As. through the Foreign Military Sales program. 

South Korea seeks to develop a twin-engine KF-X fighter jet on par with the F-16 and produce 120 units starting in 2025 to replace its the aging fleet of F-4 and F-5 fleets. aircraft. The fighter project is estimated to cost some US $16 billion.  

But the US government refused to transfer says no to transferring four out of the 25 fighter technologies South Korea wanted, citing the International Traffic in Arms Regulations. Those technologies concerned AESA, an electro-optical targeting pod, infrared search-and-rescue systems, and a radio frequency jammer. 

During the Seoul International Aerospace and Defense Exhibition (ADEX), which ran from Oct. 20 to 25, here, against that backdrop, European radar makers sought were trying to woo South Koreans apparently disappointed by the US. 

Sweden's Saab offered to develop an AESA with South Korea.

"We've done the flight test with the backend system and antenna elements," said Tom Bratt, marketing executive of Saab Electronic Defence Systems. "We're ready to go to the next phase once we have a platform available. Then we can start to make all the proper integrations."

Bratt said Saab could complete the development of the AESA system with South Korea, as the Swedish company had been engaged in a joint study on the radar AESA with the Agency for Defense Development (ADD), which is affiliated with South Korea’s arms agency. 

"Once we have a contract, it will take about two years to deliver the first system," he added.

Finmeccanica's Selex is pitching its Captor-E radar fitted for the Eurofighter Typhoon. The British and Italian aerospace group recommends Seoul adopt the Selex radar and subsequently localize it in phases.

"The bottom line is we'll try to meet the Korean demands as much as we can," a Selex official said on condition of anonymity.

"The best option right now is for Korea to produce the Captor-E radar under license first, and with Selex's tech transfer, Korea would be able to localize the AESA technology," he said.

Israel also has joined the is bidding for the AESA radar competition, capitalizing on its previous works with South Korea.  

Israel Aerospace Industries (IAI) supplied its EL/M-2032 pulse Doppler radar for the FA-50 jet, a light armed variant of the T-50 supersonic trainer aircraft. The company now is offering IAI offers the EL/M-2052 airborne AESA fire control radar for the KF-X plane. 

"We're willing and looking forward to cooperating with Korea," said Igal Karny, deputy director of Elta Systems' marketing and sales division. "The whole radar is our radar. We're exporting the radar according to our regulations," Karny said, apparently referring to Korea's wariness of AESA export control.

Unlike European and Israeli firms, US radar manufacturers were cautious when talking about AESA cooperation with Korea.

"I can only tell you that right now we don't have a license required for us to discuss KF-X radar cooperation," a Raytheon official said.

Northrop Grumman was a bit more active in participating in the KF-X effort, as it seeks to sell its scalable agile beam radar to Korea.

"We’re very interested in it, and we’re following the [KF-X] program actually," said Paul B. Kalafos, Jr., vice president of Northrop Grumman’s electronics systems. "We have a long partnership with Korea, and we want to be here for a long time in the long-term view."

Korea Aerospace Industries (KAI), which is in charge of KF-X integration, puts a priority first on reducing risk before in the wake of locally developing an indigenous AESA system. KAI favors buying an AESA either from the US or other nations to develop a KF-X prototype. 

"We favor a two-track approach toward acquiring AESA technology," a KAI spokesman said. "We can develop a KF-X jet equipped with either US or European AESA system over the next five years," he said. "In the meantime, the ADD and a foreign radar company could push for developing an indigenous AESA within 10 years at the earliest, so the next KF-X block models would be fitted with the locally developed radar."

The presidential office backs the two-track approach as a way of easing brushing public anger over US rejection of tech transfer. 

"I believe we can develop our own AESA and other key technologies within 10 years," National Security Adviser Kim Kwan-jin said in a National Assembly audit Oct. 23.

"We’re seeking technical assistance from a foreign partner in order to manage or reduce risks of independent development of key systems," he said, adding the ADD has implemented preliminary research and development of AESA since 2006. 

The ADD has been is in contact with radar companies from the US, Europe and Israel to find ways of purchasing an AESA system purchase and gaining technical cooperation, according to sources. A selected partner company is expected to work with LIG Nex1, a precision weapons maker, to develop an indigenous AESA. 

Engine Contest 
On top with the radar issue, Competition is also heating up between US and European engine companies. s heating up.Eurojet Turbo is GmbH offering its 4.5-generation EJ200 engine to power the KF-X, touting the product’s exportability and growth potential. 

"We're delighted to offer the EJ200 engine for the KF-X program. This is the latest, proven engine," said Clemens Linden, CEO of Eurojet. "The engine has an easy maintenance concept with 15 modules that can be exchanged at the base without going back to the test house."

Linden stressed Eurojet would offer lenient technology transfer so Korea could export Eurojet-based engines to third nations free of US export control.

"When the KF-X program advances and grows, we can have joint development with the Korean industry to grow the engine further," the CEO said, adding that his company will help Korea learn engine integration skills.

General Electric is pitching its F414 engine, highlighting its long experience producing engines under license with the Korean industry.

GE stresses the development roadmap for the F-414, which powers the US Navy's Boeing F/A-18 E/F Super Hornet, and GE's succesful work on a number of international programs, including KAI's T-50, the Saab Gripen and the Hindustan Aeronautics Tejas.

"KF-X is the largest ever military weapons development program in Korea's history, and it will require low-risk solutions in terms of cost, technology and life-cycle management," Al Dilibero, vice president of GE Aviation, said. "GE will bring the best and the most diverse fighter engine integration experience around the world to KF-X, which will lower overall risk of KF-X development."

KAI issued the request for proposals for the engine weeks ago and responses are due Nov. 4. The winner is scheduled to be announced by February and stands to sell about 400 engines. 

Jeff Jeong was the South Korea correspondent for Defense News.

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