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Yun-7 Turboprop Transport Aircraft
The Y-7 (Yunshu-7, or Yun-7) is a small twin-engine turboprop passenger aircraft developed by Xi’an Aircraft Industry Company (XAC) based on the Russian Antonov An-24 (NATO codename: Coke). Its cargo variant Y-7H was developed from the An-26 (NATO codename: Curl) military transport. As well as being used as a short-range passenger airliner, the Y-7 is also operated as a tactical military transport and training aircraft. The PLA Air Force (PLAAF), Army Aviation Corps, and PLA Naval Air Force (PLANAF) all currently operates the Y-7 in their air fleets.
Xi’an Aircraft Factory (now XAC) began to develop the Y-7 twin-engine turboprop passenger plane based on the An-24 Coke in April 1966. The first prototype powered by two 2,550hp turboprop engines made its maiden flight on 25 December 1970. However, the aircraft failed to pass its certification in 1977 due to its underrated engines. A second attempt to get the aircraft certified in 1979 was also unsuccessful. A revised design powered by two improved 2,900hp WJ-5A-1 turboprop engines first flew in 1980, and was finally approved for design finalisation in July 1982. The aircraft was certified for passenger flight in January 1984, with a total of 85 examples were delivered by 1992.
As the Y-7 design was already obsolete when it was introduced, XAC began to upgrade the aircraft with Western avionics in cooperation with Hong Kong-based HAECO in the mid-1980s. The improved Y-7-100 was incorporated with a revised passenger interior, Western-designed avionics, and wingtip winglets. The original five-man flight crew was reduced to three, and the number of passenger seats was increased to 52. The aircraft met the requirements for commercial passenger flight in all-weather conditions.
The further improved Y-7-200A first flew in 1993 and was certified for commercial passenger flight in 1998. The aircraft features a slightly longer fuselage, increasing the number of passenger seats to 56~60. The aircraft is powered by two Pratt & Whitney PW127C turboprop engines with the Hamilton 247F-3 propellers, giving the aircraft improved fuel efficiency and lower cabin noise. The aircraft adopts a two-man flight crew, and is also fitted with an auxiliary power unit (APU) to supply power for the air conditioning when the aircraft is on the ground. Based on the Y-7-200A XAC has also developed the Y-7-200B and MA-60 for the commercial airline market.
The cargo variant Y-7H (also known as Y-7H-500 in its commercial name) was developed in the late 1980s based on the An-26 Curl. First flying in 1989, the aircraft features a fully pressurised fuselage, two improved 3,050hp WJ-5E turboprop engines, an auxiliary turbojet engine fitted on the left engine, improved cockpit avionics, and a rear cargo door with loading ramp. The cargo cabin is also equipped with electric hinge and hydraulic transmission systems to assist the loading/unloading. The aircraft entered service with the PLA in the late 1990s. A passenger variant designated Y-7G, possibly based on the Y-7-200B or MA-60, is also in service with the PLAAF.
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Y-7G passenger plane of the PLAAF (Chinese Internet)
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The Y-7 features high-mounted wings which are equally tapered from the engines to the blunt tips. Two turboprops are mounted in pods beneath the wings, which extend beyond the wings’ leading and trailing edges. The fuselage is long and slender with an upswept rear section and a solid, rounded nose featuring a stepped cockpit. The fin is back-tapered with a blunt tip and angular fairing. Flats are high-mounted on the body, back-tapered with blunt tips, and have a positive slant.
The basic variant Y-7 is powered by two WJ-5A-1 turboprop engines, each rated at 2,900hp. The Y-7H is powered by two WJ-5E turboprop engines, each rated at 3,050hp. It also has a 900kg PY19A-300 auxiliary turbojet engine fitted on its left engine.
Variants
- Y-7 (prototype): First flying on 25 December 1970. Copy of the An-24. prototype with only 4 examples built
- Y-7: Improved production variant flying in 1980. Powered by 2,900hp WJ-5A-1 engines, with a 5-man cockpit
- Y-7-100: Passenger variant with Western avionics, 3-man cockpit, and winglets
- Y-7H: Also known as Y-7H-500. Cargo variant based on An-26 Curl
- Y-7-200A/B: Improved passenger variant with Western avionics and propellers, and 2-man flight crew
- MA-60: Further improved passenger variant for the commercial market
- Y-7G: Improved passenger variant for the PLA, possibly based on the Y-7-200B or MA-60 but with indigenous avionics and powerplants
Last update: 25 April 2007 |
