H-6 [Tu-16 BADGER] Development
The Tu-16 was a high subsonic medium bomber developed in the Soviet Union. Its development was started in 1950. Its first flight was made in 1952 and its delivery in 1955. The Badger was produced by the Soviet Union in a large quantity. The Badger is used by the CIS, Egypt, Iraq, People's Republic of China (H-6), and Ukraine. H-6 was a designation for the Chinese manufactured aircraft. The development of bombers is an important part of the construction of an independent and self-reliance aviation industry system. As early as in 1956 an agreement of assisting China to construct a medium bomber factory was reached between the Chinese and the Soviet governments. In September 1957 the Soviet government agreed to licence China to produce its medium bomber Tu-16. The process of the licenced production was:
- The Soviet Union supplied two example aircraft;
- The Soviet Union supplied China with an aircraft in the form of components for final assembly and flight test by Chinese;
- The Soviet Union supplied China with a complete kit for assembly by Chinese;
- The Soviet Union supplied China with blanks and raw materials for parts manufacturing by Chinese; and
- The aircraft was totally manufactured by China.
The Harbin Aircraft Factory started its technical reform in 1958. During the reform, its covered area was doubled and the number of general machines and large special machines were increased. Immediately after the two Soviet built example aircraft and a complete set of components for one aircraft arrived at the factory in May 1959, the factory began its intense prototype production. When final assembly began the main leading cadres including the director of the factory Lu Gang kept staying on the site of the final assembly to handle the problems encountered. The Shenyang Aircraft Factory sent 200 workers to support the final assembly according to a decision made by the Bureau of Aviation Industry. From June 28 through September 3 it only took 67 days to finish the final assembly of the first aircraft. This Chinese assembled bomber flew for the first time on September 27 and was delivered to the Air Force in December.
Starting from 1958 the Xi'an Aircraft Factory also sped up their construction and a number of industrially experienced leading cadres came to work in the factory. Liu Gang, former vice governer of Pingyuan province and director of the Luoyang Tractor Factory was appointed the director and Sun Zhiduan, former acting director of the Nanchang Aircraft Factory, the chief engineer. The Shenyang Aircraft Factory sent their 1,040 backbone technical and managerial people in all disciplines and 1,697 workers in half year. They played an important role in the construction of the Xi'an Aircraft Factory.
In 1961 the Bureau of Aviation Industry decided to transfer all the work of the H-6 prototype production to the Xi'an Aircraft Factory. The transfer was started in 1962 and completed in 1964. In order to master the manufacturing techniques the Xi'an Aircraft Factory organized their designers to make up the incomplete data of the H-6 structure analysis by the addition of 15,400 standard pages with the help from relevant organizations. On the other hand, the workers were trained in basic techniques for preparation of H-6 prototype production.
The aircraft transfered for prototype production at that time was H-6A. Its power plant was two WP8s, the fore and aft sections of the fuselage were pressurized for carrying the crew. The aircraft could carry conventional bombs as well as atomic bombs, hydrogen bombs, missiles and torpedoes. The aircraft empty weight was 37,700 kg and the maximum takeoff weight 75,800 kg.
The H-6 was the heaviest aircraft China had ever produced. There were a total of 240,000 parts in 50,000 varieties, 360,000 standard materials and 1 million rivets. It needed 150,000kg various raw materials, 25 km cables, 2 km pipes, 1,100 various bearings and 894 vendor-furnished-equipment. Its complexity in technology and heavy work load in production could not be compared by any other aircraft produced in China.
In face of such a magnificant system engineering project, the H-6's prototype production, the Xi'an Aircraft Factory started its careful and well-planned work. A general plan for the prototype production was made in 1963 and the manufacture of the production tooling started in 1964. To ensure the high precision in installment of the assembly jigs was a major technical difficulty. Lu Songshan, vice chief engineer of the factory, successfully solved the problem by combining a Soviet jig assembly machine with an English assembly jig which used an optical telescope and micrometer rods. The installment of fuselage assembly jig which was 23 m in length, 6 m and more in width and 5 m and more in height was completed in 100 days by 8 workers with Lu's method, but it would otherwise took one and half months by more than 60 5th class or above experienced fitters in two shifts with the Soviet method. The efficiency was doubled and the precision improved. The technical people at the Xi'an Aircraft Factory explored some new methods and innovations. The male moulds made of epoxy resin were used to replace the traditional metal ones, the explosive forming was used to produce corrugated sheets and the electrochemical machining was used to drill unusual holes on the landing gears and splines. These innovations were all a complete success.
In October 1966 the Xi'an Aircraft Factory completed the construction of a full size airframe for static test one year ahead of the plan. For H-6's static test there were more items tc be tested and its load applying procedures more complicated. A total of 51 test items in 105 test cases had to be tested. The static test for such a huge aircraft could not only rely on the factory alone. Therefore, the Nanchang Aircraft Factory, the NPU and the Aircraft Structure Analysi: Research Institute all worked together with the Xi'an Aircraft Factory in the test.
The static test of a full size airframe was carried out at the Aircraft Structure Analysi Research Institute. The B case suspension test was conducted on December 9, 1968. The loac was applied to 80 per cent, which proved the conformity with the design requirement an( therefore the test was good. The case A suspension destructive test was conducted on December 28 and the failure load was 134.8 per cent, which was in conformity with the design requirement and it proved the qualification of the full size airframe in strength.
On December 24, 1968 a H-6A piloted by Li Yuanyi air crew lifted off and flew into the air with the roaring of its engines. This was a significant achievement in the history of Chinese aviation industry. A series of performance flight tests showed the reliability of various systems, the normal engine operation, good controllability and stability and the conformity of main performances with the operational requirement. All the H-6As were delivered to the bomber squadrons of the Air Force and the Navy after they left the production line and they soon became an important combat force in defending the motherland. On National Day of the year 1984 18 H-6As flew over the Tian An Men Square in a formation for review.
|Join the GlobalSecurity.org mailing list|