Tian-Yi 3 / Sky Wing III or Sky Wing 3 (SW-III or SW-3)

Sky Wing (Tian-Yi or Tianyi) is a series of Chinese UAVs developed by Chengdu Aircraft Industry Group (CAIG). These are totally unrealted to the Tianyi UAVs, mainly small quadcopters, developed by Nanjing Tianyi (meaning Sky One) Unmanned Aerial Vehicles Co., Ltd. [part of Xi'an Aviation Base Tianyi Aviation Technology Co., Ltd.] Some of these UAVs are jointly developed with Nanjing University of Science and Technology.

Three members of the Sky Wing series have been revealed by their developer. The larger Sky Wing III has been frequently, but erroneously, referred to as Tianchi, or Xianglong, the name of another Chinese UAV designed by Guizhou Aircraft Industry Corporation for similar functions.

"Tianyi 3" is a reconnaissance drone system used in wartime to perform tactical reconnaissance and surveillance tasks. The 47th Paris International Aerospace Exhibition officially opened on the 18th at the Bourget Airport in the northern suburbs of Paris on 20 June 2007. A "Tianyi 3" UAV model was on display. "Tianyi 3" UAV has a total length of 8.9 meters, a height of 3.44 meters, and a maximum take-off weight of 2350 kg. "Tianyi 3" is a short-range reconnaissance drone system. It is used to perform tactical reconnaissance and surveillance tasks during wartime. The acquired reconnaissance information is transmitted to the ground surveying and mapping station in real time to provide intelligence support for the rapid mobile operations of the army.

In 2014 the media disclosed photos of China�s latest UAV ground test of the Tianyi 3 UAV of Chengfei Company. Unlike the previous pterosaurs, Tianyi 3 uses a jet engine with greater thrust and also has a stealth design, which has greatly improved performance in all aspects. From the appearance point of view, this is a high-altitude long-duration UAV with a jet engine. According to the human-to-aircraft size ratio in the photo, it can be roughly inferred that this new drone is about 9 meters in length, about 20 meters in wingspan, and about 3.5 meters in height. According to the 2007 Beijing Airshow data, Tianyi 3 was a high-altitude long-duration aerial drone with a length of 8.9 meters, a wingspan of 19 meters, a height of 3.5 meters, and a maximum take-off weight of 9 tons.

The performance index of Tianyi 3 is very close to the American Avenger drone (also known as Predator C). The Avenger UAV is 13 meters long, has a wingspan of 20 meters, and a maximum take-off weight of 8.2 tons. The Avengers are longer, mainly because it adds a built-in bomb bay, which has a stealth combat mode. The Avengers drone was under development, and the U.S. military hoped to use it to replace the active MQ-9 Reaper drone (also known as Predator B).

From the perspective of the model, the Tianyi 3 UAV uses a single-wing layout with a large aspect ratio, instead of the mid-wing of the pterosaur. The advantages of the single wing are its low aerodynamic resistance, but its disadvantages are its complex structure and heavy weight, especially the wing box cannot pass through the fuselage, and the wing root needs to be strengthened to reduce the fuselage volume utilization. The advantage of the lower single wing is that the structure is lighter, and the wing box can pass through the bottom of the fuselage, which is conducive to arranging the fuel tank in the middle of the fuselage, but its disadvantage is large aerodynamic resistance. However, after optimized design, the resistance can be reduced to an acceptable level, so many long-range aircraft, especially passenger aircraft, now tend to use the lower single wing.

It can also be seen from the model and pictures that the wings of the Tianyi 3 UAV have a certain swept angle, similar to the American Avengers and Global Hawk UAVs. The swept angle of the Avenger wing is about 6 degrees, and its maximum speed index is 720 km / h, which is 50% higher than the 460 km / h of the death drone. Tianyi 3 UAV should also pursue high-speed performance, so that it can respond quickly to surrounding emergency events.

The most interesting aspect of the Tianyi 3 drone is its engine. Judging from a photo taken from the rear angle, the aircraft seems to have a dual-engine design. The dual-engine structure has a large volume and weight, which will reduce the range and dead time of the drone, which is exactly high altitude and long flight time.

The V-shaped vertical tail, special shaped engine nozzle, and fuselage fold line of Tianyi 3 adopted more stealth measures. From the Tianyi 3 UAV model and photos from its early tests, it is almost certain that it is a single-engine aircraft. This change in the nozzle of the rear engine should be optimized in response to the need for stealth. In the original design of the Tianyi 3 UAV, the engine is the original circular convergent nozzle, the high-temperature airflow is directly discharged into the air, although there is a V-shaped vertical tail cover, but the infrared and radar signal characteristics are relatively strong. With such a design, the engine nozzle is not directly exposed, but is shielded. Although it will cause thrust loss, it can improve the stealth performance of the aircraft.

The optimization of the stealth aspect of the Tianyi 3 UAV also includes that the fuselage has an obvious fold line, the upper and lower surfaces are inclined inward, and it has a certain refracting power for the side-illuminated radar waves. The V-shaped vertical tail is adopted, the back air inlet is S-shaped, and the raised nose of the nose has a certain cover, which shows that the aircraft is required to be used in a high-strength environment, which is not the same as the U.S. Avenger drone.

Another reason the new type of UAV may be single-engine, not dual-engine, is the engine matching problem. The U.S. Avengers UAV uses Pratt & Whitney Canada's PW500 small turbofan engine, which has a thrust of about 1.77 tons. Among Chinese engines, the closest to it is the Turbofan-11 which equipped the a K-8 trainer, which has a thrust of 1.7 tons. The Turbofan 11 is a domestic model of Ukrainian AL-222 turbofan engine. In addition to thrust, the dimensions and weight indicators of the two are basically the same. The length of the PW500 is about 1.8 meters, the turbofan-11 is 1.9 meters, the weight is about 350 kilograms, and the thrust-to-weight ratio is about 4.9-5.

But the American engine has better performance in terms of fuel consumption and reliability. The take-off fuel consumption of the PW500 is about 0.48, while the Turbofan-11 is 0.6. From this perspective, China does not need to use two engines to piece together the thrust, so the possibility of Tianyi 3 UAV adopting a single-engine design is great.

Judging from the coloring of the fuselage, the raised part of the Tianyi 3 UAV's nose should be a satellite communication system. Below is the equipment bay, which can be installed with synthetic aperture radar, photoelectric load, electronic reconnaissance system, and optical reconnaissance system.

According to U.S. military indicators, the maximum speed of the Avenger drone can reach 740 km / h, the empty time is about 20 hours, the range is more than 10,000 kilometers, and it can continue on duty for more than 16 hours at a distance of 2900 kilometers from the base. Considering the industrial gap between China and the United States, the performance of the Tianyi 3 UAV may not be comparable to the Avengers, but if it can be approached, it can significantly improve China's military long-range reconnaissance and surveillance capabilities.

China had two main types of UAVs, BZK-005 and Pterodactyl (military number "Attack 1"). BZK-005 has a cruising speed of about 150-200 kilometers, a dead time of more than 40 hours, and a range of more than 5,000 kilometers. The pterodactyl is a "chat-in-one" drone with a cruising speed of 180 km / h, a dead time of more than 20 hours, and a range of 4,000 km. Its maximum take-off weight is about 1200 kg and its payload is 350 kg.

The service of BZK-005 and pterosaurs has improved China's army's ability to grasp the surrounding situation. The former has a combat radius of about 1,500 kilometers, and the latter has about 1,000 kilometers. BZK-005 takes off from Hainan to cover the Nansha Islands to the south, to the Bus Strait to the west, to take off from the southeast coastal airport in China, to the southeast to cross the first island chain, into the Pacific Ocean, and to the northeast to the coast of Japan, especially at Diaoyu Island stays for more than 24 hours to achieve real-time monitoring and control of the Diaoyu Island waters, effectively improving the army's ability to monitor surrounding events.

However, there is still a certain gap between these two types of drones compared with similar equipment in the U.S. military. First of all, they use propeller-powered drones. They are slow, have a small maximum take-off weight, and have a limited load. Both are below 200 kilometers / hour, while the U.S. Army Global Hawk UAV has a cruise speed of more than 600 kilometers / hour, which is three times the previous two. It takes about 7 hours for BZK-005 or Pterosaur to take off from Hainan to reach Nansha or the Bus Channel. It also takes about 6 hours to take off from Xisha to Nansha. It also takes about 2 hours from the southeast coast to the sky over Diaoyu Island. This time is too long.

In addition, the payload of the BZK-005 UAV is only about 100 kg, and it can only perform reconnaissance tasks. The pterosaur drone is slightly larger, with a payload of 200 kilograms, and has been upgraded to a "cha-tan" drone. However, the pterodactyl carried only two anti-tank missiles when performing reconnaissance strikes, and its attack capability was weak. All indicators were similar to those of the U.S. Predator UAV. For the first time, the Pterosaur drone can only carry two anti-tank missiles.

According to the U.S. military �s recent experience in counter-terrorism operations in Afghanistan and Iraq, Predator drones are generally not used for strike missions. The real protagonist of the "beheaded" terrorist is the MQ-9 Reaper drone. The maximum take-off weight of the Grim Reaper drone reaches 4.76 tons, more than four times the predator; the maximum load is 1.7 tons, more than eight times the predator. Reaper drones can carry anti-tank missiles, laser-guided bombs and other precision-strike ammunition. The key is a 500-pound laser-guided bomb. When bombing larger buildings, it can ensure the killing of terrorists in the house, and only rely on hell fire to counteract it. Tank missiles cannot do this.

Objectively speaking, although the Tianyi 3 uses a turbofan engine as its power, its performance indicators are similar to those of the U.S. Avengers. However, a key requirement of the U.S. military for the Avengers drone is stealth strike. Like the F-22 and other stealth combat aircraft, it has an in-house ammunition bay. The ammunition is built to ensure stealth performance during the attack. The U.S. death drone can carry a lot of strike loads. The Tianyi 3 with turbofan engine should be stronger.

In general, the emergence of the Tianyi 3 drone filled the gap and improved the army's drone combat system. In future counter-terrorism operations, the army can use pterosaurs to perform reconnaissance missions, and Tianyi 3 UAVs to perform strike missions. In high-intensity conventional wars, Tianyi 3 can perform tactical reconnaissance tasks, Xianglong drones perform strategic reconnaissance tasks, and Sharp Sword drones perform attack tasks.