Harbin Y-11 CHAN

The Harbin Yun-11 / Y-11 transport aircraft is a light twin-piston engine light transport aircraft developed by the Chinese aviation industry. In 1974, China Harbin Aircraft Factory (abbreviation: Hafei) proposed an idea, and the first flight was successful on December 30, 1975. The Y-11 transport aircraft has good low-speed performance, wide cockpit, good vision, low take-off and landing requirements, and easy use and maintenance. With the approval of the State Council of China, Hafei formed an agricultural aviation service team for the Y-11 aircraft.

To meet the increasing need of the national economy and to develop a better new aircraft, the aircraft industry began to develop by themselves small general purpose transports in 1970s. This twin-engined utility aircraft was designed and developed in China as a potential replacement for the Y-5 (Chinese-built An-2). Design of the Type 11 Transport Aircraft, or Yunshuji 11 (Y-11) began during the mid 1970s as a replacement for the Antonov An-2 utility biplane in Chinese service (licence built in China as the Y-5).

In November 1974 the government assigned a task to the Harbin Aircraft Factory to develop a small transport Y-11 and Xiong Wenjie was appointed chief designer. The design drawings were completed in June 1975 and the prototype production began immediately after release of the drawings. The full size airframe static test was passed on December 19. A prototype was built and flown at Shenyang on 30 December 1975, while pre series and production aircraft were built at what is now the Harbin Aircraft Manufacturing Company. The type design was certificated in 1977 Construction of a small preproduction series of about 15 aircraft began in 1977 and these were used in top-dressing and pest control operations in 1977-78. Production Y-11s were built from 1980.

The Y-11 is a general purpose airplane which is mainly used in agriculture and forestry but as second missions it can also be used for geological exploration, detection of shoals of fish, transportation and rescue. The safety and low altitude performance were emphasized in the design. It can fly at minimum low altitude and features short takeoff and landing run distances. It is powered by two domestic HS6D piston engines, maximum payload is 1,250 kg and an air crew of 8 members can be carried.

In order to serve the economy construction with the Y-11 and to test the aircraft performance in practice it was approved by the government in May 1980 to set up an Air Service Team by the Harbin Aircraft Factory. With the Y-11s the team has provided various professional aviation services. In past several years the Y-11s have flown to more than 10 provinces, e.g. Heilongjiang, Inner Mongolia, Hebei, Anhui, Jiangsu and Guangxi, and provided services such as insects killing, seeds sowing and fertilizer applying for agriculture, forestry and animal husbandry, geological exploration and aerial survey for industries and survey of wild animal resources such as red-crowned cranes and northeast tigers. When Mudanjiang region was suffering a plague of insects in May 1981 several Y-11 were sent to spray pesticide and a kind of worldwide harmful moths were quickly wiped out with a rate of killing over 90 per cent. In 1982 the Y-11 s flew to Xinjiang and operated for forest belts and farmlands with good effect. In 1984 the Shihezi Production and Construction Corps in Xinjiang Autonomus Region bought 10 Y-11s and set up an Air Service Detachment to carry out their professional operations. Another Y-11 Air Service Detachment was set up in the same year in the city of Changzhou in Jiangsu Province.

Crew of two on flight deck, with separate forward-opening door on port side for access. Dual controls. Cabin accommodates seven passengers normally (with removable folding jump seat for an eighth passenger), or equivalent cargo. Cargo/passenger double door on port side of fuselage, in line with wing trailing-edge.

As a light multi-purpose transport aircraft, the Y-11 has the advantages of good low-speed performance, wide cockpit, good vision, low take-off and landing requirements, and convenient use and maintenance. However, the Yun-11 also has the problems of low reliability of the aircraft and engine, short overhaul interval, and the power of the two piston-6 D-type engines is still insufficient, the commercial horsepower is relatively small, and the operation economy is poor.