South Korea has selected the Lockheed Martin APG-67 radar for its planned Samsung KTX-II light combat aircraft/advanced trainer. The radar is also being pushed in Taiwan as an alternative to the APG-66, following the collapse of Northrop Grumman's F-5 upgrade venture with Aerospace Industrial Development (AIDC).

The Korean air force has opted for the APG-67 over the Northrop Grumman APG-66 (V) radar for its tandem-seat KTX-II. Local access to technology and the flexibility to sell the system to third-party operators are believed to have been factors in the decision.

US Government regulations restrict local industrial access to parts of the APG-66 system, such as critical source codes. The rival APG-67, however, is not in US military service and "-as a commercial radar, offers advantages over a foreign military sales system," says a Lockheed Martin source.

Seoul has been pressing Washington for the right to export the KTX-II, an issue which was potentially complicated by the use of a radar that is also a standard fit on the Lockheed Martin F-16.

The air force plans to purchase 94 KTX-II fighters between 2005 and 2009. Samsung needs to export the aircraft for a return on its 17% stake in the $2 billion development.

Under South Korea's teaming agreement with the USA, it has responsibility for the selection and procurement of the radar, elements of which will be produced locally. Samsung's partner and 13% stakeholder in the programme, Lockheed Martin, is developing the KTX-II's avionics systems and flight controls, as well as the wing. GEC-Marconi is to supply the aircraft's head-up display.

The collapse of Northrop Grumman's F-5E/F Tiger IV upgrade partnership with Taiwan's AIDC has set back the APG-66 even further. The two companies had been planning to modernise an F-5 by the end of 1998, to act as a demonstrator for the Taiwan air force and for export (Flight International, 20-26 August).

US Government hesitation in allowing Taiwan to produce the APG-66 locally has been cited as one factor. The APG-67 is now viewed as an alternative radar, a version of which, known locally as Golden Dragon 53, is already produced under licence by AIDC. This is fitted to the Ching-Kuo Indigenous Defence Fighter.

Northrop Grumman is also believed to have had differences with AIDC over funding for the demonstrator. The US company says that it is now looking for an alternative partner. The Taiwan air force plans to retain 90 of its 250 F-5E/Fs and has a longstanding requirement for a limited avionics upgrade, while AIDC wants to upgrade and to sell the remainder.

Source: Flight International