Taiwan’s Aerospace Industrial Development Corporation (AIDC), the state-owned aerospace company overseen by the Ministry of Economic Affairs, has rolled out the first XAT-5 prototype of its new AT-5 Yung Yin (Brave Eagle) Advanced Jet Trainer (AJT). The ceremony took place on September 24, attended by President Tsai Ing-wen. Formerly known as the Blue Magpie, the AT-5 was re-named following a public competition.

The AJT program is intended to provide a replacement for the Republic of China Air Force’s (RoCAF) fleet of Northrop F-5 advanced trainers and indigenous AIDC AT-3 basic trainers, which are scheduled for retirement in the early 2020s.

Initially, Taiwan planned to acquire 66 Alenia Aermacchi M-346 Masters to meet the AJT requirement, signing a $2.1 billion MoU (memorandum of understanding) with Finmeccanica in 2014, after also evaluating the South Korean KAI T-50 Golden Eagle. Italy was to have built the first four to six aircraft with the rest being assembled in Taiwan with 50 percent Taiwanese-made components and extensive technology transfer.

When the newly elected President Tsai Ing-wen took office, her strongly nationalist Democratic Progressive Party government pledged that Taiwan would develop its own advanced trainer aircraft. Leonardo-Finmeccanica reportedly reduced the price of its M346 offer by about 25 percent, but this new offer was rejected.

Taiwan considered a modernized AT-3 MAX with a lightweight composite airframe, a glass cockpit, upgraded avionics, increased thrust, and an integrated training system, before settling on the AT-5, a simplified derivative of the existing two-seat operational conversion trainer version of the indigenous F-CK-1 IDF Ching Kuo fighter. AIDC had been offering simplified versions of the IDF for Lead-In Fighter Training (LIFT) for some 20 years, but the AT-5 represents an all-new take on this approach. It was formally selected in 2017, and construction of the first prototype began in June 2018.

The AT-5 and its associated training system were designed by the Taoyuan-based National Chung-Shan Institute of Science and Technology [NCSIST], the Ministry of National Defence’s R&D agency, which will subcontract manufacture to the Aerospace Industrial Development Corporation at Taichung.

Compared to the Ching Kuo fighter, the AT-5 has 80 percent new-design components, will make greater use of composites, and will have derated F125 engines without afterburning, limiting it to subsonic/transonic speeds in level flight. The aircraft will also have greater internal fuel capacity than the operational variant, but may not carry underwing fuel tanks. The airfoil will have a revised, slightly thicker section for lower approach and landing speeds, while the landing gear will also be redesigned. The internal cannon will be deleted, though there will be provision for armament (probably including a gun pod) and the aircraft will feature a new AESA radar and new avionics.

In 2018 AIDC announced that the first prototype would be rolled out in September 2019, while the Ministry of National Defence has said that the prototype will make its maiden flight in June 2020. Four prototypes will be produced (two of them for static and fatigue testing, two for flight tests) before low-rate production begins in November 2021. Higher rate "mass production" is scheduled to begin in March 2023. The aircraft will be delivered to Taitung first to replace the RoCAF’s F-5E/F Tigers and then to Kangshan to replace the AT-3 fleet.

Total program cost has been estimated at $2.2 billion, and the program has already created 1,200 new jobs in Taiwan with 800 more expected by 2021.