China's Y-20 Heavy Operational-Strategic Transport: A Hybrid Of An-170, An-77 And Il-76MD
Sergey Goncharov
MOSCOW DEFENSE BRIEF
China’s efforts to create its own strategic military transport fleet coincided - though not entirely by accident - with the break-up of the former Soviet Union. Those efforts were spurred by the new opportunities for military hardware importers which opened up thanks to the crisis in the USSR and, in later years, in the former Soviet republics. The first Chinese contract for three Il-76MD transports was signed by the Tashkent Chkalov Aircraft Production Company (TAPOiCH), an Uzbek aircraft maker, in 1990. The planes were delivered to the Chinese in July-October 1991. They were assigned to the Chinese Air Force, although formally they were given civilian registration numbers and the color scheme of China United Airlines, a commercial carrier. In 1992 China placed an order for another seven Il-76MDs, which were delivered in September 1993- February 1994. A year later Beijing ordered another four aircraft, delivered in 1996. All 14 Il-76MD transports bought by China were given the local designation Y-13, and assigned to the Chinese Air Force’s 13th Air Division, based at the Danyang airbase in Hubei Province.1 Even though the aircraft have the Il-76MD Soviet/Russian designation, they are not equipped with a defensive cannon unit at the rear, and their outward appearance is similar to the civilian Il-76TD model. In addition, after 1991 China bought at least six used Il-76MD aircraft from Uzbekistan. 2
Another stage in the development of China’s strategic military transport fleet began a decade later. In September 2005, during the 12th session of the Russian-Chinese intergovernmental commission on military and technical cooperation, Rosoboronexport and China’s National Defense Ministry signed a contract for 34 Il-76MD transports, four Il-78M aerial refueling tankers, and 51 spare D-30KP-2 engines, worth a total of 1.045bn dollars. TAPOiCH was assigned the role of the main subcontractor. Deliveries were due to commence in 2007 and finish in 2012.
But then the Uzbek company began to play for time; it tried to revise the terms of the contract in an effort to get a better deal. Its primary argument was that about 95 per cent of the aircraft’s components had to be imported from Russia, making the final product more expensive. Besides, it soon turned out that the Tashkent-based company simply could not resume mass production of the IL-76 in such a short time - most of its specialists had quit, and there was no-one left to assemble such a large batch of aircraft. TAPOiCH could guarantee the delivery of only 16 planes - that is how many finished airframes it had left from previous years. As a result, in March 2006 TAPOiCH rejected the unit price which had already been agreed with the Chinese, and refused to sign the sub-contract with Rosoboronexport. The Chinese contract fell through.3
It is only in late 2006 that the Russian MoD officially announced that TAPOiCH would not be able to meet the deadlines under the latest Chinese contract. But less than a month after the Tashkent company refused to sign the subcontract with Rosoboronexport - namely, in April 2006 - Chinese trade representatives in Ukraine approached ANTK Antonov, a Ukrainian aircraft maker. They said China wanted the Ukrainian company’s help in developing a new operational-strategic transport. That request went beyond the scope of the already agreed areas of Ukrainian-Chinese cooperation in aircraft design and manufacture. (ANTK Antonov took part in the China-2000 AirShow in Zhuhai on November 6-12, 2000, where it signed a cooperation agreement with China’s AVIC II aircraft corporation. The two companies agreed to work together on upgrading China’s An-12 and Y-8 aircraft to the Y-8F600 specification, and on bringing the An-2 / Y-5 fleet to the An-3 specification, which has a turboprop engine. Two years later ANTK Antonov signed another deal at the AirShow China-2002 event, a design contract with AVIC I. The Ukrainian company undertook «to conduct the entire range of works related to designing the wing of the ARJ 21 future regional aircraft»)4. The Ukrainians said they were ready to provide the required assistance. A few months later a large Chinese delegation, which included representatives of the Chinese MoD and of the Industry and IT ministry, came to Kiev for a low-key visit to discuss the details.
As an alternative to the Uzbek-Russian Il-76MD transport, the Ukrainians offered the Chinese the An-70, which had already entered limited production. After a brief pause - which the Chinese probably made for diplomatic appearances’ sake - that offer was turned down. One of the reasons was the insufficient maximum payload the An-70 can carry (47 tonnes, whereas the combat weight of China’s Type 98 main battle tank is 48 tonnes, rising to almost 50 tonnes when the MBT is equipped with an extra fuel tank and detachable self-entrenching gear5). Even more importantly, the maximum range of the An-70 with maximum payload is only 1,350 km. The Chinese wanted at least 3,650 km, which is what the Il-76MD offers, and would have preferred the figure to go as high as 4,000 km or more.
Another reason why Beijing refused to consider entering the An-70 into service with the Chinese Air Force was the D-27 turbofan engine used on that aircraft. To begin with, the Chinese knew that the engine had turned out to be fairly unreliable during the first phase of the An-70 flight tests in Ukraine. Besides (and perhaps more importantly), they had decided that it would be impossible to launch production of such a complex engine at China’s own factories. The Chinese military asked instead that the future transport be equipped with the tried and tested Russian D-30KP-2 engine, which China’s own industry was already gearing to start making under the local WS-18 designation.
ANTK Antonov said the wishes expressed by the Chinese could be accommodated. By early 2007 it had set up a new VTL (Heavy Transport Aircraft) working group, which was soon given the green light to start developing a heavy transport using the existing designs for the An-77, a turbojet version of the An-70, which had earlier been put on hold. (Officially, however, ANTK Antonov, which is the head company of the Antonov State Enterprise, is merely providing advice and consultation to the team designing the new aircraft.) The take-off weight of the aircraft was increased from 132 tonnes to 187 tonnes, and its maximum payload went up from 47 to 50 tonnes. (The volume of the cargo bay was increased by adding a 2-meter insert in the airframe in front of the center-wing section.) The original An-77 design relied on four CFM56-5A16 bypass turbofan engines; these were replaced by four D-30KP-2 bypass turbofan engines in the Y-20. The aircraft retained its ability to take-off and land using short landing strips, although the take-off length went up to 900m. (The solution for increasing the thrust is the same as the one used in the An-77. It was first introduced in the C-17A Globemaster III and boils down to directing the exhaust jet of the bypass turbofan engine at the high-lift flaps. In the An-70 extra lift is achieved by using the SV-27 propfan, which sits on the D-27 engine’s shaft, to blow a stream of air at the wing.)
Work on this design, which was initially designated as the Y-XX, continued for three years. It is widely believed that first information about the Y-XX, which by that time had been re-designated as the Y-20, was published on December 23, 2009 by the China Military Aviation portal. The report referred to the Y-20 military transport being developed in China by Xian Aircraft Industrial (Group) Corporation. In actual fact, however, first news about the project appeared on the discussion boards of Russian aerospace news websites almost a year before the article on the China Military Aviation website - namely, in the autumn of 2008. When the new aircraft was “declassified” in that article, its specifications were still very similar to those of the Il-76, with a maximum take-off weight of 200 tonnes and a maximum payload of 50 tonnes. The prototypes and the first mass-produced aircraft were expected to be fitted with the Russian D-30KP-2 engines. The later versions of the Y-20 were to be equipped with the Chinese clone of that engine, the WS-18, or its WS-118 modification. The first Y-20 prototype was slated to take to the air in 2012.7
But serious changes were made to the Y-20 design in 2010. The reason for that is thought to have been the entry into service with the Chinese army of the Type 99-IIA main battle tank, also known as the Type 99A2. The combat weight of this tank, which has many similarities to Germany’s Leopard IIA6, is 58 tonnes.8 That has translated into greater payload requirements for the Y-20, which is still expected to be able to carry even the heaviest tanks now in service with the Chinese Army. As a result the whole project has switched to a different underlying design by ANTK Antonov, the An-170, which is another variation of the An-70. The An-170 is a heavy operational-strategic transport which Antonov worked on in the late 1980s - early 1990s. The project was in competition with the Il-106, a rival design by the Ilyushin Bureau. The Il-106 was announced the winner by the Soviet authorities, but owing to the crisis which ensued after the break-up of the Soviet Union neither aircraft went into production. The An-170 is much larger and heavier than the An-70, with a take-off weight of 230 tonnes and a maximum payload of 60 tonnes. Another difference is the »regular» wing profile of the An-170, whereas the An-70 uses the so-called «supercritical» profile. The latest version of the Y-20 project still relies on the four D-30KP-2 bypass turbofan engines. Naturally, this means that the excellent short take-off and landing specifications of the original design are now out of the question- but there is every reason to believe that these specifications are still fairly good by normal standards.
Development of the Y-20 appears to be nearing completion, although the deadline for the maiden flight of the first prototype may still be pushed back a little. In a press release of May 12, 2011 XAIC confidently promised that the aircraft would take to the air before the XVIII Congress of the Communist Party of China, which is scheduled for later this year. But that press release was later removed from the company’s official website.9
The Y-20 project has given a new lease of life to the D-30KP engine, which is made in Rybinsk for the Il-76 aircraft. (The version in production since 1982 is the D-30KP-2, which can maintain its thrust specifications at higher surrounding air temperatures.) Despite its venerable age, the engine, which was launched in 1963, still remains in production thanks to Chinese custom. According to the press service of NPO Saturn, a contract between Rosoboronexport and China for 55 D-30KP-2 engines, to be delivered by 2012, entered into force in April 2009. The first batch was delivered to the customer in November 2009, another thee batches followed in March-October 2010, and the final fifth batch of 11 engines was delivered in March 2011. Although these five batches are sufficient to fit almost all the Il-76 aircraft currently in service in China with new engines, the Chinese have recently placed an even larger order. In late 2011 they signed a contract with NPO Saturn for 184 new D-30KM-2 engines, to be delivered over four years.10 Beijing is not saying what it needs those engines for - but it seems clear that most if not all of them will be installed on the Y-20 transports.
Project specifications of the AVIC Y-20 heavy transport11
Maximum payload, tonnes 60-65
Maximum speed, km/h 750-800
Service ceiling, m 13,000
Service range with maximum payload, km 4,400
Dimensions, m
Length 49
Wingspan 50
Height 15
Wing surface, square meters 310
Maximum take-off weight, tonnes 220
Empty weight, tonnes 100
Engines: type C… number C… engine thrust Bypass turbofan D-30KP-2, 4C…12,000 kg(f)
Crew 3
1. A. Manyakin, A. Fomin. KJ-2000. China's all-seeing eye in the sky/Vzlyot, No 11, 2009.
2. K. Chuprin, China's power in the sky, Harvest, Minsk, 2007.
3. O. Sharifov, Dead loop for TAPOiCH/Fergana - international news agency, November 15, 2010 (
).
4. S. Goncharov. Taking off in parts/Defense Express, No 7-8, 2006.
5. China's military equipment and hardware. Issue One. Tanks. Otvaga.narod.ru Internet project, Saransk, 2003.
6. V. Shunkov. Special purpose planes, Harvest, Minsk, 1999.
7. Aviatsiya i vremya, No 1, 2010 (Panorama section).
8. A. Berdnikov, China's Type 99A2 main battle tank/Zarubezhnoye Voennoye Obozreniye, No 1, 2012.
9. China's new heavy transport could take to the sky in 2012 - June 28, 2011 - Fifth-Generation Aircraft (
... 06-28-1968).
10. A. Fomin. The Russian aircraft engine industry. Yearly results and plans / Vzlyot, No 4, 2012.
11. Table compiled from the following sources: bmpd - Chassis for China's Y-20 future transport (
), SATURN Research and Production Company. Corporate website (
).
Print version
... just an idea but wasn't it widely reported that the Y-20's unveiling (or even first flight) might be "coordinated" with the 18th Congress of the Chinese Communist Party", which is scheduled to start in Beijing on November 8, 2012. 
