The CJ-6 ( basic trainer aircraft) is an all-original Chinese design that is commonly mistaken for a Yak 18A. Its predecessor, the Nanchang CJ-5, was a licence-built version of the Yak-18. However, advancements in pilot training brought a need for a new aircraft with improved performance and a tricycle landing gear. When the Soviet Union developed the Yak-18A, PLAAF engineers decided that its performance and design would not suit China's needs.
The aircraft was designed in 1958 by the Nanchang Aircraft Factory (now Hongdu Aviation). As the Shenyang Aircraft Factory already had experience building the Shenyang JJ-1 begun technical research for the CJ-6, more than 20 Shenyang designers were transferred to Nanchang, including chief designers Tu Jida and Lin Jiahua. Xu Shunshou and Huang Zhiqian, then China's top aircraft designers, were also involved.
During late 1957 Aeronautical Engineers Cheng Bushi and Lin Jiahua began work in Shenyang on a trainer design that addressed the shortcomings of the Yak-18A. The design they delivered featured an aluminum semi-monocoque fuselage, flush-riveted throughout, and introduced a modified Clark airfoil wing design with pronounced dihedral in the outer sections. The dihedral and an angular vertical tail distinguish it externally from the otherwise rather similar Yak-18A. Wind tunnel testing validated the design, and in May 1958 the program was transferred to the Nanchang Aircraft Manufacturing factory where Chief Engineer Gao Zhenning initiated production of the CJ-6. The first flight of the CJ-6 was completed on August 27, 1958 by Lu Maofan and He Yinxi.
Power for the prototype was provided by a Czech-built horizontally-opposed piston engine, but flight testing revealed the need for more power, so a locally manufactured version of the Soviet AI-14P 260 hp radial, the Housai HS-6, was substituted along with a matching propeller, and with that change the CJ-6 was approved for mass production. In 1965 the HS-6 engine was upgraded to 285 hp and redesignated the HS-6A, and the aircraft equipped with the new power plant were designated the CJ-6A.
A total production run estimated at more than 3,000 aircraft supplied CJ-6 aircraft for PLAAF training, as well as for export (as the PT-6) to countries including Albania, Bangladesh, Cambodia, North Korea, Tanzania, and Sri Lanka.
It is expected Hongdu/Yakovlev joint developed CJ-7 Trainer (L-7) primary trainer will replace CJ-6s in PLAAF.