Sunday, 30 September 2012

The PLA’s Unmanned Dragons

Of the several events that took place on June 30 last year within the People’s Republic of China to coincide with the date of the 90th birthday of the Communist Party of China (CPC) and to demonstrate the CPC’s indispensible role in bringing about the ‘New China’, the one that has enormous national and regional security implications for South Asia was the low-key rollout of the People’s Liberation Army’s (PLA) latest high-altitude long-endurance (HALE) unmanned aerial vehicle—the Xianglong Soar Dragon—one of three such turbofan-powered UAVs that have been under development since 1999 and have been inducted into service since 2005. The other two remaining HALE UAVs, the WZ-9A (also referred to as the Wuren Zhencha-2000, or WZ-2000) and the Sky Wing (Tian Yi-3), along with the Soar Dragon, are all powered by a single licence-built Ivchenko AI-25TLK twin-shaft medium-bypass turbofan (known locally as WS-11) developed by Ukraine’s Motor Sich, and rated at 3,800lb (16.9kN) thrust. All three HALE UAVs--featuring V-tail configurations have been co-developed by the Chengdu Aircraft Corp (CAC) and the Guizhou Aircraft Industry Corp (GAIC), and are likely to be employed—apart from undertaking intelligence, surveillance, targetting and reconnaissance (ISTR) tasks--as unmanned combat aerial vehicles (UCAV) and unmanned radar/communications jammers as well

Presently, all medium-altitude long-endurance (MALE) and HALE-UAVs are considered strategic assets and placed under the direct command of the 2nd Department the Central Military Commission’s General Staff Department (GSD). Thus far, 52 new UAVs developed by 70 state-owned R & D institutions have emerged. Three Chinese companies--ASN Technology Group, China Aerospace Science and Industry Corp (CASIC), China Aerospace Science and Technology Corp (CASC), Zhuhai Yintong Energy, Weifan Freesky Aviation Industry Co, and AVIC Defense—account for most of the UAVs and UCAVs built thus far. Presently, ASN Technology is China’s largest UAV manufacturer, with a history of developing UAVs and target drones since 1958. The company works closely with the Xian-based Northwestern Polytechnical University’s UAV Institute, and the Beijing- and Nanjing-based Universities of Aeronautics and Astronautics, Beijing Technology Company, Hebei Electric Power Reconnaissance Design Academy, Northwestern Polytechnical University, Shaanxi Engine Design Institute, GAIC, and the Chengdu Aircraft Design and Research Institute.

The WZ-9A from the CAC/GAIC combine was unveiled in November 2000 at the Airshow China expo in Zhuhai. Having a length of 7.5 metres, wingspan of 9.8 metres, 1.7-tonne maximum takeoff weight, cruise speed of 800kph, combat radius of 800km, endurance of 3 hours, and a service ceiling of 18,000 metres, it also features radar cross-section reduction features, including a flat-bottomed surface blended seamlessly with long swept-wings. Its maiden flight took place on December 26, 2003, following which its on-board 80kg ISTR mission avionics/sensor payload began being flight-tested from August 2004. Although the aircraft has smaller dimensions, it is intended to fly at a service ceiling of 18,000 metres with a reported maximum speed of 800km/h for a total endurance of only 3 hours. The mission payload includes an X-band KLC-6 synthetic aperture radar (SAR) developed by China’s CETC International. A single WS-11 turbofan sits on top of the tail section, with its intake shielded by the wing section and its exhaust nozzle shielded by two V-shaped tailfins extending 40° outwards to reduce both radar and infra-red signatures. A large satallite communications antenna is located inside its head-bulge for real-time transmission of images and ELINT data back to its ground control station. The WZ-9A also carries a chin-mounted turret containing a thermal imager. It entered limited service with the PLA’s GSD in 2007 and conducts only strategic reconnaissance missions. An improved version of the UAV, known as WZ-9B, was unveilled in November 2006 and is now being developed as a stealthy HALE-UCAV and will be armed with internally mounted precision-guided munitions like the FT and LT family of small-diameter bombs, AKD-10 laser-guided anti-armour missiles, and TY-90 within-visual-range air combat missiles. Yet another variant of the WZ-9A is an as yet unnamed operational turboprop-powered strategic ISTR platform featuring 66-feet wingspan and a horizontal stabiliser linking canted outward twin-tails. The first flying prototype was rolled out in October 2008, and its maiden flight took place in November 2009.

The Sky Wing (Tian Yi-3) UAV, optimised for tactical ISTR tasks, was unveilled in November 2006. A functional prototype had been built by April 2008, and its maiden flight took place in September 2008. Built by the CAC/GAIC combine, it has a length of 7.5 metres, wingspan of 9.8 metres, maximum takeoff weight of 1.7 tonnes (including an 80kg mission payload, cruise speed of 800kph, service ceiling of 59,000 feet, and a loiter time of 3 hours. The box-wing Xianglong Soar Dragon UAV was first revealed in November 2006 by the  Chengdu Aircraft Design and Research Institute. It is 14.3 metres long, has a 25-metre wingspan, takeoff weight of 7,500kg with a payload of 650kg, cruise speed of 750kph, cruise range of 7,000km, and a cruise altitude of 18km. Maiden flight of the Xianglong Soar Dragon was successfully conducted on November 7, 2009 at 12:21pm at the Anshun airport and lasted 18 minutes. The Soar Dragon’s joined wing and tail configuration considerably increases the UAV’s range and payload and produce better handling at high altitudes. Joined wings—a subset of closed-wing systems—comprise a sweptback forward wing and a forward-swept aft wing. In the Soar Dragon the rear wing is higher than the forward wing to reduce the effect of the forward wing’s downwash on the rear wing’s lifting qualities. The rear wing has a shorter span than the front wing and its downturned tips meet the front wing at a part-span point. Advocates of the joined wing claim that its advantages stem from the fact that the front and rear wings are structurally cross-braced. This allows a higher aspect ratio while keeping down weight and staying within flutter limits. A higher aspect ratio reduces drag due to lift, and because the wings are both slender and short-span (relative to a single wing with equivalent lift) the wing chords are short, which makes it easier to achieve laminar flow. The joined wing also can reduce trim drag. It is believed that the Soar Dragon will an ISTR platform optimised for broad area maritime surveillance and for providing over-the-horizon targetting information for long-range anti-ship cruise missiles.  
Yet another MALE-UCAV now being promoted for export is AVIC Defense’s Pterodactyl-1 medium-extended long-endurance UCAV, which was developed by the Chengdu Aircraft Design & Research Institute, and has undergone a series of flight trials, including weapons launches, since late 2009. Powered by a 700kgf-thrust turbofan, the Pterodactyl-1’s total payload capacity is 200kg, of which the FLIR turret or even a SAR weighs about 100kg, leaving 100kg of weapons (like two AKD-10 missiles) to be carried under each wing. The UCAV is 9.05 metres long and 2.77 metres high, with a 14-metre wingspan. Maximum takeoff weight is 1,100kg, maximum endurance is 20 hours, maximum operating altitude is 5,000 metres, maximum range is 4,000km, and maximum cruise speed is 280kph.

No comments:

Post a Comment