Xian Y-20

Y-20
Y-20 at Zhuhai Airshow 2014
Role Strategic airlifter
National origin People Republic of China
Manufacturer Xi'an Aircraft Industrial Corporation
Designer Tang Changhong / 唐长红
First flight 26 January 2013
Status Under development
Primary user PLA Air Force
Number built 3 prototypes [1]


The Xian Y-20 (Chinese: 运-20) is a large military transport aircraft. The project is being developed by Xi'an Aircraft Industrial Corporation and was officially launched in 2006.[2] The official codename of the aircraft is Kunpeng (Chinese: 鲲鹏).[3] after the mythical bird of ancient China that can fly for thousands of kilometres.[4] However, within the Chinese aviation industry itself, the aircraft is more commonly known by its nickname Fat Girl (Chinese: 胖妞), because its wide fuselage in comparison to other Chinese aircraft previously developed in China.[5]

Design and Development

The general designer of the Y-20 is Tang Changhong (Chinese: 唐长红),[6] the general designer of Xian JH-7. The deputy general designer of Y-20 is Guo Zhaodian (Chinese: 郭兆电).[5]

Utilization of Chinese indigenously developed composite material in the construction of Y-20 is considered by Chinese as a major achievement for several reasons. Although China has developed various composite materials and widely adopted them in the aircraft manufacturing prior to the Y-20 program, these composite materials could not meet the strict requirements of western standard, issued by FAA or EASA, so majority of the composite material used had to be imported from west for Chinese passenger jets such as Comac ARJ21 or Comac C919 aimed to receive FAA or EASA certification.[7] To avert this problem, a design team headed by the Aerospace Research Institute of Materials and Processing Technology (航天材料及工艺研究所), also known as the 703rd Institute of the 1st Academy of China Aerospace Science and Technology Corporation (CASC) was formed in March 2009 and after spending nearly three years, the joint design team finally succeeded in developing several types of composite material for Y-20 that meet all the requirements of FAR Part 25.835d.[8] In addition to utilizing Chinese indigenously developed composite materials qualified to be used on Airbus and Boeing passenger jets on Y-20,[7] another equally important milestone in the Chinese aviation industry resulted from the Y-20 program is that for the first time, China has established the comprehensive evaluation and certification system for composite materials used on aircraft based on FAA system.[8]

The Y-20 is the first cargo aircraft to use 3-D printing technology to speed up its development and to lower its manufacturing cost.[9] Model-based definition (MBD) is also used, and it's the 3rd aircraft to utilize MBD technology in the world, after Boeing 787 (2005) and Airbus A380 (2007).[10] A project team to implement MBD for Y-20 program was formally formed in October 2009, and after the initial success in application on the main landing gear, MBD application was expanded to the entire aircraft and became mandatory for all contractors and sub contractors of the Y-20 program.[10] The implementation of MBD was initially met with strong resistance, with only a third of suppliers agreed to implement MBD, but the general designer of Y-20 declared those who refuse to do so will be banned from participating in Y-20 program, thus forcing everyone to comply, resulting in increase in productivity.[10] The implementation of MBD greatly shortened the time required, for example, without MBD, installation of wings takes a month or two, but with MBD adopted, the time is drastically shortened to just a few hours, and in general, the design work reduced by 40%, preparation for production reduced by 75%, and manufacturing cycle reduced by 30%.[10]

In addition to 3-D printing, Y-20 is also the first aircraft in China adopting associative design technology (ADT) in its development, the second aircraft to do so in the world, after Boeing 787.[10] Headed by the deputy general designer of structural design, Mr. Feng Jun (冯军), the initial attempt to implement ADT actually failed after two months spent on application on the nose section. It was only after the second attempt that took another three months on the application on wings didADT became successful.[10] The adaptation of ADT greatly shortened the development time by at least eight months, and modification of wing design that previously took a week is shortened to half a day.[10]

Cargo is loaded through a large aft ramp that accommodates rolling stock. The Y-20 incorporates a shoulder wing, T-tail, rear cargo-loading assembly and heavy-duty retractable landing gear, consists of three rows, with a pair of wheels for each row, totaling six wheels for each side. The structural test was completed in 194 days as opposed to the 300 days originally planned, thanks to the successful development and application of an automated structural strength analysis system.[10] In comparison, similar work for Xian JH-7 took a year.[10] According to the deputy general designer, the shortest take-off distance of Y-20 is 600 to 700 meters.[5] Y-20 incorporates a total of four LCD EFIS, and the development of EFIS for Y-20 utilizes virtual reality via helmet mounted display.[5] Eight types of different relays used on Y-20 are developed by Guilin Aerospace Co., Ltd. a wholly own subsidiary of China Tri-River Aerospace Group Co., Ltd.(中国三江航天集团), which is also known as the 9th Academy of China Aerospace Science and Industry Corporation (CASIC).[8]

It was reported that the Y-20 started ground testing from December 2012, including runway taxi tests.[11][12][13][14] The aircraft made its maiden flight lasting one hour on January 26, 2013.[15][16][17] During landing in first flight, it was reported that the Y-20 prototype bounced once before finally settling on runway due to high landing speed.[18] In December 2013, a new Y-20 prototype took to the sky.[1]

Propulsion

The first Y-20 prototype is powered by four D-30 series turbofan engines. The initial batch of Y-20 will most likely use the D-30; while the mass production aircraft will be equipped with WS-20 engines, which is derived from the Shenyang WS-10 turbofan engine currently powering the J-11B fighters in PLAAF, or SF-A, another turbofan engine currently under development by Shenyang Engine Design and Research Institute.[10]

The WS-20 engine is essentially a WS-10A engine with high by-pass ratio of around 6.2, it produces around 14 tons of thrust and does not have the military afterburner nozzle.[19][20] In contrast, SF-A is a technically conservative high-bypass turbofan of CFM56 class, with an output of 28700 lb of thrust and not attempting to reach the latest technology level of new Western engines.[10]

Chinese air force demand

According to some Chinese sources such some scholars from PLA National Defence University, the Chinese air force PLAAF will need at least 300-400 Y-20 aircraft to conduct military operations in different battlefronts along the Asia-Pacific region as well as to catch up with capabilities of the U.S and Russia. This will require XAC to open two production lines and run for 10 years or 15 years.[21][22] However, such claim are disputed by other Chinese scholars, because Y-20 currently does not incorporate advanced technologies used on C-17, such as externally blown flap and winglets, and the width of the cargo compartment of Y-20 is not wide enough either,[23] so it's logical to assume a modified new design based on experience gained from Y-20 will be developed, and as a temporary measure, Y-20 produced in the next few years will probably only be numbered 50-100 in order to make room and leave resources for the future large transport aircraft.[23]

Specifications (estimated)

General characteristics

Performance

See also

References

Notes
  1. ↑ 1.0 1.1 http://net.chinabyte.com/351/12807851.shtml
  2. ↑ "China's first heavy transporter Y-20 takes off". english.people.com.cn. Retrieved 26 Jan 2013.
  3. ↑ "Y-20 gives air power a push". chinadaily.com.cn. Retrieved 28 Jan 2013.
  4. ↑ Dave Sloggett, "THE DRAGON Gains its Strategic Wings" Air International, March 2013, pp. 94-95
  5. ↑ 5.0 5.1 5.2 5.3 "Y-20". Sina Corp. Retrieved February 15, 2014.
  6. ↑ 6.0 6.1 "New jumbo transport jet completes more tests". East Day. Retrieved 5 March 2013.
  7. ↑ 7.0 7.1 "Composite material used on Y-20". Retrieved February 25, 2013.
  8. ↑ 8.0 8.1 8.2 "Components used on Y-20". Retrieved February 5, 2013.
  9. ↑ "央视首次曝光运20运输机驾驶舱内部珍贵画面_军事_环球网". Retrieved 4 February 2015.
  10. ↑ 10.0 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8 10.9 10.10 "Development of Y-20". Retrieved August 8, 2013.
  11. ↑ "Y-20 transport aircraft starts testing, first flight completed". AirForceWorld.com. Retrieved 24 Dec 2012.
  12. ↑ "Chinese Y-20 revealed in new online pictures". Flightglobal.com. Retrieved 27 Dec 2012.
  13. ↑ "IN FOCUS: China’s new strategic airlifter". Flightglobal. Retrieved 14 Jan 2013.
  14. ↑ David Axe (4 January 2013). "Satellites Spot China’s Mysterious New Warplane". Wired. Retrieved 29 January 2013.
  15. ↑ 15.0 15.1 "我国自主发展的运—20大型运输机首次试飞取得圆满成功". news.xinhuanet.com. Retrieved 26 Jan 2013.
  16. ↑ "视频 国产大型运输机运-20首飞成功". news.cntv.cn. Retrieved 26 Jan 2013.
  17. ↑ "视频 国产大型运输机首飞成功：我国运输机发展之路". news.cntv.cn. Retrieved 26 Jan 2013.
  18. ↑ "VIDEO:Y-20 prototype first flight completed". news.cntv.cn. Retrieved 26 Jan 2013.
  19. ↑ http://www.janes.com/article/31880/china-marks-aviation-milestones-with-j-10b-production-second-y-20-prototype-flight
  20. ↑ http://www.popsci.com/chinas-new-more-powerful-aircraft-engine-ws-20-takes-sky
  21. ↑ http://baike.baidu.com/redirect/c85c0qgiWQyHgKfndnFwhelJIyCgnvrTD7yboh856IMDrZr6Xuy%2BVdNKaCT%2FEI8zdi8%2BvYCdlnGw%2BK9oR1RNjAfolmePODddSJgXsV1bvXM
  22. ↑ "China Eyes 400 Y-20 Cargo Planes For Military Transport". DefenseWorld.Net. Retrieved 10 November 2014.
  23. ↑ 23.0 23.1 "Y-20 production". Retrieved November 18, 2014.
  24. ↑ 24.0 24.1 http://eng.chinamil.com.cn/news-channels/pla-daily-commentary/2013-01/28/content_5197556.htm