CJ-5 Trainer Aircraft

A primary trainer is used for training potential trainees to master primary flying techniques because of its low speed, good controllability and stability. These factors make the task of learning simpler. The CJ-5, manufactured by Nanchang Aircraft Factory, was a licence production of the Soviet primary trainer Yak-18 developed in 1946. It had a frame type fuselage, a wing with one rectangular center panel and two tapered outer panels and a tailwheel type landing gear. A piston engine drove a wooden propeller. The flying instruments, engine instruments, a transceiver, a directional gyro and an interior communication system, etc. were installed to enable the trainees to learn the operational skills of the aircraft after they had finished the primary training program.

The Nanchang Aircraft Factory started to repair the Yak-18 aircraft early in 1951 and, the aircraft assembly and test techniques were grasped during the repair period. In 1952, the factory started to expand the scope of repair, and to produce spare parts and to get themselves familiarized with the techniques of producing aircraft parts and assemblies. 1953 was the year of more active preparation for the transition from repair to manufacture. The factory set up the goal of mastering manufacturing techniques of Yak-18 parts and components which could be interchanged and matched on the aircraft. 44 main assemblies of outer wings, flaps, empennages and landing gears etc. were manufactured according to the repair documentation and sample parts. These parts were assembled on one aircraft for test and checkout and good result was witnessed after the aircraft underwent 50 sorties and 78 hours of flying. The method of using lofting, templates and master parts was adopted for the manufacture of aircraft parts from the second half of 1952.

With this method correct aircraft configuration, and interchangeability and matching of parts could be ensured, hence the first and most important step was taken towards the manufacture of a complete aircraft. In early 1954 when the factory was formally set to trial produce the primary trainer CJ-5, 235 aircraft had already been repaired. People in the Nanchang Aircraft Factory made all aircraft parts with the only exception of control system.

In accordance with the First Five-year Plan of the aviation industry approved by the government, the trial production of the CJ-5 was to be completed in September, 1955. But it was decided to cut this by 1 year as the Chinese Air Force was in urgent need of a primary trainer and the Nanchang Aircraft Factory had already mastered aircraft repair techniques, and techniques for manufacture of parts and components for 5 types of aircraft including the Yak-18.

After the visit to the factory by Minister Zhao Erlu of the Second Ministry of Machine Building at the end of 1953, he believed that the conditions for manufacturing complete aircraft was matured ahead of schedule. An order was issued to the factory after the approval of the State Council, by which the time for formal successful trial production of the CJ-5 primary trainer was changed from the third quarter of 1955 to an earlier time of the third quarter of 1954.

After the order had reached the factory, the people of the factory were mobilized immediately and the trial production was carried out day and night. The factory proceeded rapidly under the instruction of some Soviet experts and the organization of chief engineer Li Shaoan and chief technologist Gao Yongshou. First CJ-5 was delivered to the flight test station in June for flight test on June 30 and second full size airframe began its static destructive test on May 12. The first aircraft successfully completed its test flight on July 11, 1954. The State Certification Committee arrived at the conclusion: The performance of the primary trainer CJ-5 manufactured by the Nanchang Aircraft Factory met the requirement of the specification and it could be used by the Air Force as a trainer aircraft. On August 26, the Defence Minister Peng Dehuai approved the batch production of the aircraft. Only more than half a year was used from trial production to batch production. The power-plant of the aircraft M-11 engine was also trial-produced successfully by the Zhuzhou Aero Engine Factory in August of the same year.

Aircraft static destructive tests were totally new to the factory at that time and this was the first of its kind ever carried out even in China. There were no Soviet experts for consultation. A project engineer, Zhang Azhou who studied in the United Kingdom and had just returned to China, was put in charge of the test. Zhang Azhou asked all his staff members to study all available Soviet data on static testing and made careful preparation for the test. Under his orderly command load applying, instrument reading and data measuring and recording were carried out as planned. When the load was increased to 105-110 per cent of the ultimate load, a sudden thundering sound came out and the airframe broke at the front spar of outer wing panel. This was a proof that the strength of airframe was in conformity with design criteria and this first destructive static test of a full size airframe was a complete success. Later on the static tests were also successively carried out in 57 design cases on 14 major components, e.g. central wing panel, aileron and fuselage, showing that their strength was in compliance with design criteria. All static tests of CJ-5 had been thus completed and the strength of the aircraft was proven. Zhang Azhou made an outstanding contribution to the static test programme and, therefore, was awarded a special-class merit.

The first flight of the first aircraft made in new China, the CJ-5, took place on July 3, 1954. Piloted by Duan Xianglu, the aircraft had a successful flight and made a safe landing. On July 20 the State Flight Test Commission came to the conclusion that the performance of CJ-5 was in conformity with its specification and therefore it was agreed that the aircraft should be put into mass production and be delivered to the Air Force for use in training. A celebration of the successful production of the first CJ-5 was held at the factory on July 26. Zhao Erlu, minister of the Second Ministry of Machine Building, Shao Shiping, the governer of Jiangxi province, Duan Zijun, deputy head of the Aircraft Industry Bureau, and other leaders from the Air Force came to the celebration. Three CJ-5s made a flight demonstration. A telegram reporting the success to Chairman Mao Zedong from all staff and workers of the Nanchang Aircraft Factory was passed during the celebration.

After the mass production of CJ-5 was approved in August 1954 a total of 379 CJ-5s were produced from 1954 to 1958 and delivered to the Air Force, the Navy air force and CAAC. The CJ-5 made a great contribution to the training of pilots in the early days of new China.

The success in manufacturing CJ-5 Aircraft marked a good start for aircraft manufacture in new China. The Chinese aviation industry had entered a new stage. To celebrate this achievement, Chairman Mao Zedong signed two letters of praise and encouragement to the Nanchang Aircraft Factory and Zhuzhou Aero Engine Factory on August 1 and August 10 of 1954 respectively. In his letter of praise and encouragement to the Nanchang Aircraft Factory, Chairman Mao Zedong said: "Your report of July 26 had been received. Congratulations to the successful trial production of the first Yak-18 aircraft. This is a good start in establishing both aircraft industry and strengthening the national defence of China. I hope the factory will continue their efforts to further master technology and improve quality under the guidance of the Soviet experts and ensure the fulfilment of regular production task." Zhu De, Commander in Chief of PLA, also wrote words of encouragement to the Nanchang Aircraft Factory saying: "Carry on the enthusiasm and creativeness of the working class; strengthen national defence and defend the motherland."