South Korean plan to develop a fifth generation fighter aircraft had hit a roadblock following U.S. refusal to share four critical technologies.
The indigenous KF-X fighter program was envisaged to develop a twin engined multi role stealth fighter that is more advanced than the F-16 fighter but less than the F-35.
The Defense Acquisition Program Administration (DAPA) says U.S. has refused to grant export license for key technologies including Active Scanned Electronic Array (AESA) radar, Infra-red Search and Tracking (IRST) system, Electro-Optical tracking system and next generation radio frequency jammers.
These core technologies are key to stealthiness of the aircraft other than physical parameters including shape and radar absorbing coatings.
These technologies were to be transferred as a part of offsets for Korean purchase of 40 Lockheed Martin F-35A stealth fighters, allowing indigenous production. Lockheed offered 21 technologies for the KF-X program as part of F-35 selection.
The refusal will further delay the KF-X introduction to 2025 against the planned 2021.
Following the development, South Korean government has launched a investigation into the KF-X program and DAPA's selection of F-35.
Lockheed Martin won the deal over the stealth feature of F-35, by beating Boeing F-15SE Silent Eagle and Eurofighter Typhoon bids, who offered much better technology transfers.
Korean Aersospace Industries (KAI) was selected to develop the KF-X with Indonesia having 20 percent share in the program. The South Korean requirement was estimated at 120 fighters and Indonesia having requirement for 80.
Lockheed Martin has helped the KAI to develop the T-50 Golden Eagle supersonic jet trainer aircraft.