South Korea has officially begun an effort to develop and build their own jet fighter (KFX) to replace its aging U.S. built F-4 and F-5 fighters. The KFX is intended to be an aircraft somewhere between the F-16 and the F-35 and will have some stealth capabilities. The KFX is expected to enter service in about ten years now that the government has found the cash and foreign partners to make it happen. Indonesia will be a partner in this effort by contributing 16 percent of the $8.5 billion required. South Korea will buy at least 120 KFXs while Indonesia will buy up to fifty as the first export customer. Indonesia will also get access to some of the technology and build some of the components.
The KFX is currently seen as a single seat 24 ton fighter with two engines and the ability to carry more than six tons of weapons. Some of these weapons can be carried in an internal bomb bay, increasing stealthiness. The KFX is expected to look more like the Eurofighter Typhoon, than the T-50 or F-16. The KFX is based on only costing $60 million each, having advanced electronics (including an AESA radar).
South Korea has been trying to assemble the cash, technology and export orders for KFX since 2001. This was part of an effort to create South Korean military aircraft development and building capability. The problem with KFX has always been cost and a lack of partners. One of the major problems, recently overcome, was the United States finally agreeing to transfer several key military technologies KFX needed. This was delayed because of American security concerns, as East Asian nations (like Japan several times in the past) have proved vulnerable to China spies obtaining key military technologies. Not just the specifications but the more difficult to obtain details of actually manufacturing such tech. Most of the technologies the U.S. would not give South Korea access to were only available from a few sources, or only the United States. Eventually South Korea struck a deal to obtain 21 key technologies used in the F-35.
Another reason for the KFX delays was that several studies by South Korean analysts pointed out that the KFX would cost up to twice as much as a top-of-the line model of the F-16 bought from the United States. Critics also pointed out that Japan made the same mistake in the 1990s when they decided to develop and build a similar (to the KFX) aircraft; the F-2. It cost twice as much as an imported F-16 (or even one built in Japan under license) and was justified (unofficially) as a way to provide lots of good jobs. The F-2 did little to aid exports because Japan cannot, by law, export weapons.
South Korea can and does export weapons and actively sought partners to build the KFX. Indonesia first agreed in 2010 to jointly develop the KFX. That deal fell apart because of costs as did several similar deals with other countries. The cost problem is less of an issue now because of the growing popular enthusiasm for developing the ability to design and build combat aircraft. South Korea worked out solutions here as well and believes they can learn from the Japanese experience as well as their own recent success in developing and producing the TA-50 jet trainer/attack aircraft.
South Korea learned much while developing and manufacturing its TA-50 jet trainer. That effort began in the 1990s and the TA-50 entered service in 2005 as a 13 ton, two seat, single engine aircraft. More importantly the TA-50 is also available as a combat model (the F-50), which carries a 20mm autocannon and up to three tons of bombs and missiles.