AVIC 601-S

AVIC 601-S is an unmanned aerial vehicle development program containing series of Chinese low-observable flying wing UAVs jointly developed by Shenyang Aircraft Design Institute (SYADI) of Aviation Industry Corporation of China (AVIC) and Shenyang Aerospace University (沈阳航空航天大学). The name 601-S derives from the names of the developers: SYADI of AVIC is also widely known as the 601st Institute, hence 601, and the letter S is for Shenyang Aerospace University (SAU). A total of seven different models have been identified as of 2013.

Sky Crossbow
Sky Crossbow (Tian-Nu or Tiannu, 天弩) experimental UAV is the first member of 601-S series to reveal the Chinese effort to gain experience about the flying wing design. Although a flying wing, Sky Crossbow still retains the twin tails to ensure flight control, and hence named 4 control surfaces, flying wing with twin tail (Si duo-mian fei-yi jia shuang-chui-wei, 四舵面飞翼加双垂尾). Specification:
 * Length: 2.15 m
 * Wingspan: 2.2 m
 * Height: 0.6 m
 * Weight: 18.8 kg
 * Speed: 70–150 km/h
 * Power plant: Electrically powered ducted fan

Wind Blade
Wind Blade (Feng-Ren or Fengren, 风刃) experimental UAV is the development of earlier Sky Crossbow with very similar specifications. The primary difference between Wind Blade and earlier Sky Crossbow is that the twin-tail is replaced by winglets. The configuration of Wind Blade is adopted by NUAA Unmanned flying wing, another completely unrelated Chinese experimental UAV developed by Nanjing University of Aeronautics and Astronautics for the same purpose of gaining experience in the flying wing design, and thus the two designs look very similar externally.

Cloud Bow
Wind Blade is further developed into Cloud Bow (Yun-Gong or Yungong, 云弓) experimental UAV, and by this stage the satisfactory result of flight control system of the flying wing design has been achieved, so the winglets on earlier Wind Blade is eliminated, and hence Cloud Bow is also called 4 control surfaces flying wing (si duo-mian fei-yi, 四舵面飞翼).

Warrior Eagle
Warrior Eagle (Zhan-Ying or Zhanying, 战鹰) experimental UAV is based on earlier Cloud Bow and the difference is that Warrior Eagle is a forward swept flying wing design. Many Chinese internet claims have postulated that Warrior Eagle will be deployed as a reconnaissance or even an unmanned combat aerial vehicle (UCAV), although this might be true in some distant future, the developer has however claimed at various airshows and UAV exhibitions that the main purpose of this UAV is to gain knowledge of flight control system for a forward swept flying wing design, though there are future applications of reconnaissance and combat missions if the design is proved to be successful.

Sharp Sword
Sharp Sword (Li-Jian or Lijian, 利剑), jointly developed by SYADI, SAU and Hongdu Aviation Industry Group (HAIG), is one of the two models of the AVIC 601-S progressed further than proof of concept design by evolving into larger size (the other being Dark Sword). The Sharp Sword is jet-powered and has a wingspan of 14 meters. It’s not yet known the precise mission Sharp Sword is assigned, but possible missions would including reconnaissance and eventually combat missions. On Nov 21 2013, Sharp Sword conducted a 20 minute long maiden flight from HAIG's airfield.

Dark Sword
Knowledge gained on other 601-S UAVs has been applied to Dark Sword (An-Jian or Anjian, 暗剑) UAV, which has less emphasis on stealth in comparison to other 601-S UAVs, but instead, more emphasis is on maneuverability. As with Warrior Eagle, the capability of Dark Sword has been greatly exaggerated by many claims on the Chinese internet. However, the developers have stated that the primary focus of Dark Sword is to develop it into a hypersonic UAV, in order to fulfill the requirement of a low-observable, high maneuverability, hypersonic UAV to support tests conducted for Chinese air defense and air-to-air weaponry. Retired Shenyang J-6 can only achieve supersonic speed at level flight, but the main purpose of retired Chengdu J-7 is to provide spare parts for the existing J-7 fleet currently in service after the production has ended. Dark Sword is thought to be possible in the distant future to be developed into other applications such a s reconnaissance and combat. To improve maneuverability, it adopts canard configuration and twin tails.

Shape Varying UAV
Shape Varying UAV (Bian-ti Wu-ren-ji, 变体无人机) is an experimental UAV of AVIC 601-S series and it was first revealed in 2008 during the 7th Zhuhai Airshow, and it is a proof of concept UAV of flying wing configuration, based on experience gained from other members of the series. Greater wingspan provides better stability at low speed, while at high speed, lesser wingspan would help to reduce drag. Instead of the usual variable-sweep wing configuration, Shape Varying UAV is designed to explore the potential of folding wing design. As with other members of the AVIC 601-S UAVs, the inlet of Shape Varying UAV is above the fuselage.