Design of the advanced jet trainer began in 1975 with a conventional low-wing configuration with a tricycle undercarriage, tandem seatcockpit, and twin turbofans mounted in nacelles on either side of the fuselage. After the design was approved in 1978, two prototypes were produced. The first aircraft rolled out on 17 July 1980 and made its maiden flight on 16 September 1980. Further evaluation resulted in a contract for 60 AT-3As for the ROCAF. The AT-3 is a low-wing monoplane with a straight wing and a conventional slab tailplane. The AT-3 has five weapon mounts and wingtip launch rails. There are two Zero-zeroMartin-Baker 10 ejection seats in the tandem dual-control cockpit of production models. The rear seat is elevated 30 cm to allow better over-the-nose visibility. There's a rarely used small bomb bay feature in the aircraft, now mostly holding an auxiliary fuel tank. AT-3 has two Honeywell/Garrett TFE731-2-2L non-afterburning turbofan engines, producing a total thrust of 3178 kg. It is able to carry various size iron bombs, rocket pods, AIM-9 Sidewinder missiles and locally produced TC-1 IR Air-to-air missiles.
Operational history
The first AT-3A operator is the Flight Training Command in ROCAF Academy. In 1988 the Thunder Tiger demonstration team replaced its F-5E aircraft with AT-3s. On 9 September 1989 the 35th Combat Squadron replaced its Lockheed T-33 Shooting Star trainers with AT-3s painted in SE Asia jungle colors. The AT-3s delivered to the 35th Combat Squadron were equipped with semi-recessed twin 12.7 mm machine guns in the bomb bay. The 35th Squadron later relocated to ROCAF Academy for logistic reasons, and later stood down in 1999 with its aircraft transferred to the Flight Training Command. The aircraft operates both as an advanced trainer and for weapons training, and all AT-3 in service with ROCAF are now painted in the Thunder Tiger's Blue, White and Red colors. The AT-3 went through a mid-life update from 2001 to 2006, which will allow the aircraft to operate beyond 2016. The XA-3 Lui Meng single-seat attack version never progressed beyond the prototype stage. Two such aircraft were built, numbered 901 and 902. These aircraft are now retired and on display. AT-3B #825 is on loan to AIDC. These three aircraft were able to carry a shortened version of the HF-2 air-launched Anti-ship missile, and were combat-ready with this version of missile during the 1995/1996 Third Taiwan Strait Crisis. The armed two-seat AT-3B upgrade did enter service with the ROCAF.
AT-3B : Two-seat ground-attack aircraft for the Republic of China Air Force. 45 of the 60 AT-33A aircraft have been planned for upgrades to the AT-3B standard which includes APG-66Tradar and a head-up display as its mid-life update project. The status is not currently known.
XA-3 : Single-seat ground-attack aircraft. Two prototypes built but program was cancelled due to priorities placed on the AIDC F-CK-1 Ching-kuo. Retired and on display.
