2. Military UAV: 2020 vertical take-off and landing accelerate military application
2.1 Unmanned aerial vehicles: "New species", profoundly changing the face of warfare
In the use of warfare, UAVs can greatly improve the cost-effectiveness ratio of combat operations. UAVs can replace manned aircraft in combat, which can greatly reduce the cost of stand-alone aircraft, combat equipment systems, and actual combat while also reducing the loss of humans, a valuable combat resource.
1) The purchase cost of a single UAV is much lower than that of a manned aircraft with the same function and level. The purchase cost of the U.S. military "Blackbird" strategic reconnaissance aircraft is about 1.5 to 2 billion U.S. dollars per unit, while the "Global Hawk" strategic reconnaissance drone only costs 100 million U.S. dollars per unit, which only accounts for 1/15 of the unit price of human and aircraft procurement. . Transforming decommissioned manned aircraft into unmanned aerial vehicles can also bring huge cost advantages. In 2017, Boeing accepted a contract from the military to transform 18 F-16s fighter jets into QF-16 UAVs by adding artificial intelligence systems to serve as "loyal wingmen" for manned aircraft. The cost of each UAV is only 1.38 million U.S. dollars, which is almost negligible compared with stealth fighters that can easily cost hundreds of millions of dollars.
2) UAVs can significantly reduce the total cost of the U.S. aircraft carrier fleet by 81%. According to the "Comments on UAVs and Future Combat", comprehensive analysis from multiple aspects such as dispatch rate, fuel consumption, maintenance cost, etc., in the future, the aircraft carrier formation can purchase 144 UAVs to replace the original 361 manned aircraft, reducing the cost from about 900 100 million U.S. dollars fell to 17 billion U.S. dollars. After the use of UAVs, the total cost of three aircraft carriers is only equivalent to the total cost of the current two aircraft carriers under the condition that the combat capability of each aircraft carrier remains unchanged.
3) Significantly reduce pilot training costs and extend combat time. Manned aircraft pilots take a long time to train and cost a lot. Take the US F-15 fighter pilots as an example. The training time is up to 2.5 years, and the total cost exceeds 10 million U.S. dollars. In contrast, the training time for drone operators usually only takes 120 hours, and the training cost is much lower. In terms of combat time, UAVs require only a small amount of time for maintenance and training, and most of the time can be used to perform combat tasks. On the other hand, manned aircraft usually only spend 1/3 of the time in actual combat deployment, and 2/3 of the time is spent on training and maintenance.
In addition, UAVs are a "new species" of military equipment: they are upgraded and iteratively fast and gradually develop into an integrated inspection and combat; they also have a high proportion of battle damage and have consumable attributes. Chinese military drones are gradually upgraded from pure reconnaissance to integrated detection and combat. At present, military drones include Changkong-1, Changhong-1, ASN series, WZ-2000, BZK-005, Pterosaur series, Xianglong, Sharp Sword, Rainbow series, and Yunying. Among them, the Pterosaur series, the Rainbow series, the sword, and the cloud shadow are all integrated surveillance drones, which were all newly launched after 2000, while the pure reconnaissance drones mainly include the Xianglong and BZK-005 reconnaissance Man-machine. According to statistics, the American Predator A has produced a total of 550 aircraft since it was put into actual combat in 2001 and has lost more than 300 aircraft so far, with a battle damage ratio as high as 54.4%. In contrast, the US F15 series fighters have produced 894 aircraft in total. So far, more than 109 aircraft have been lost, and the battle damage ratio is only 12.2%. Therefore, compared with manned aircraft, drones are consumable weapons.
UAVs have profoundly changed the face of warfare. At the same time, military use has also promoted the strong demand for UAV systems, leading to the development of cutting-edge technologies. The military UAV system emphasizes that it meets the requirements of advanced technical and tactical performance, high reliability, confidentiality, and security in complex combat scenarios and extreme use environments. Therefore, the development of military UAV systems requires more advanced and complex Supported by a specialized technological, industrial system, while constantly innovating and applying cutting-edge technologies in the fields of high-performance materials, new energy power, artificial intelligence, and electronic information and driving new directions for technological development.
UAV cluster combat is an important form of air combat in the future, and China Electronics Technology will display the drone swarm launch vehicle. Manned and unmanned coordination, distributed air operations, and group operations are listed as important forms of future air operations. High-performance UAV systems are the top priority for future intelligent airpower construction. The drone swarm technology specifically refers to the large-scale self-organizing network and self-formation technology of drones. As an engineering construction unit engaged in a large-scale electronic information system for military and civilian use of the country, China Electronics Technology demonstrated the latest drone swarm launch vehicle on October 14, 2020. The system can adopt two methods: ground launch and air launch. The launch vehicle used for ground launch can store and launch 48 drones at one time. Air launch is by means of helicopter throwing, and the UAV launches autonomously when it is in the air.
2.2 Current situation: Chinese military drones have profound technology and are well-known in the international market
The critical components of Chinese military drones have achieved localization. The first is the body material. In recent years, with the rapid development of Chinese material industry, domestic high-quality carbon fiber manufacturers have continuously emerged, and the rainbow body material can be produced nationwide; second, the electronic core components, drones do not have large-scale computing, and high-precision Image processing does not use high-end chips, so it is not subject to Western sanctions and blockades. Third, in terms of engines, many engines used by Rainbow have been localized, and related localization tests have been completed, which can realize domestic-made engine alternatives.
At present, China's military UAV engines are mainly aviation piston engines. However, China's development of integrated drones and small turbofan/turbojet engines will be indispensable in the future. Compared with piston engines, turbofan/turbojet engines have larger thrust-to-weight ratios, faster speeds, and higher flying altitudes. In November 2018, China Aviation Development demonstrated the AEF50E turbofan engine, AEP50E turboprop engine, and AEF20E turbojet engine at the Zhuhai Air Show used for UAV engines, filling the gap in the power of UAVs that China urgently needs.
In addition to the localization of critical components, the production capacity has also been significantly increased. The pulsating production line can produce 200 Rainbow UAVs per year. Unlike traditional production lines with fixed stations, the pulsating production line is an uninterrupted and fast-flowing automated production line. It is currently the most efficient assembly production line in aviation manufacturing and can guarantee modern fighter aircraft's mass production and delivery. In January 2020, the Rainbow UAV pulsation production line newly constructed by China Rainbow UAV Technology Company made its debut. The Rainbow UAV production line has six stations in total, and each station corresponds to detailed and accurate process content. The connection between the six stations is through a guide rail. The pulsating production line has the traditional station's assembly features and can realize the rapid flow of equipment production. In addition to this pulsation production line in Taizhou, Zhejiang, Rainbow UAV Technology has also built multiple pulsation production lines in Gu'an, Hebei. The total output of all pulsation production lines of Rainbow-4 and Rainbow-5 can be maintained at about 200 a year.
At the same time, Chinese military drones are also favored by the international market, with a market share second only to the United States. The Pterosaur series are the main export models. From 2000 to 2019, a total of 1,609 drones were exported worldwide. From 2000 to 2004, the global export of drones averaged only 33 aircraft per year; and from 2005 to 2019, the number of global drone exports increased significantly, reaching an average of 97 aircraft per year. According to exporting countries, the United States exported 474 UAVs from 2010 to 2019, accounting for 48.0% of the global UAV export market. China followed closely behind, ranking second in the world with a market share of 25.3%. In terms of models, the Pterosaur series UAVs are the main export models of China, accounting for 64%; the Rainbow series UAVs account for 28%, second only to the Pterosaur series.
The UAV production line has crossed the country, occupying UAVs' primary market in the Middle East. In March 2017, Saudi Arabia introduced the Rainbow UAV production line. The presented "Rainbow-4" is equipped with satellite communication antennas. The weapons mounted are mainly AR-1 laser-guided short-range air-to-surface missiles and FT-9 guided bombs. . Before this, the "Rainbow" UAV production line has been exported to Pakistan and Myanmar. Chinese companies represented by Pterosaurs and Rainbows have occupied the primary UAV market in the Middle East. According to the exporting countries, Saudi Arabia, Egypt, and the United Arab Emirates purchased 68% of Chinese exported drones from 2010 to 2019.
2.3 The future: vertical take-off and landing (VTOL) is one of the development trends of UAVs
2.3.1 Vertical take-off and landing-the top ten critical future equipment of the U.S. military
Because it is not restricted by take-off and landing sites and can adapt to complex terrain environments such as navigation and mountains, the United States has listed the vertical take-off and landing aircraft as the top ten critical equipment of the U.S. military in the future. There are two main technical routes for vertical take-off and landing fixed-wing UAVs. 1) Tilt-rotor UAV: The lift and thrust required for the two stages of vertical take-off and landing and forward flight are provided by rotating the engine direction. The representative model is the "Eagle Eye" version of the carrier-based UAV of the American V-22 Osprey And Chinese Rainbow-10 etc. 2) Rotor-fixed-wing composite type: adopts two sets of power systems, the rotor provides vertical lift, and the propulsion engine powers the fixed-wing model. The representative models include JOUAV 's the "CW " series, Rainbow CH804D, etc.
The electric propulsion system can replace complex mechanical transmission components and optimize the configuration of the tilting rotor. The tilt-rotor configuration can improve flight efficiency under the premise of ensuring good vertical take-off and landing performance, thereby taking into account the vertical take-off and landing capability and cruising economy. Compared with the rotor configuration, it can significantly increase the range. The research, development, and application of tilt-rotor technology have been in use for decades. Models such as V-22 have been widely used in special operations and other scenarios. However, the tilt-rotor aircraft that uses traditional power systems has its engine power output mechanism and rotor. It requires highly complex mechanical transmission components, which significantly increases the platform's complexity and weight and has a particular impact on reliability. The application of the electric propulsion system effectively avoids the above risks. The motor can be directly placed at the tilting wing assembly, and the electric power is transmitted through the cable to drive the motor. There is no need for power transmission components, which significantly reduces the mechanical structure's complexity, and its maintenance characteristics can be guaranteed.
Compared with the tilting rotor configuration, the fixed rotor wing's mixed design simplifies the structure and avoids the tilting components' influence. Rotor-fixed-wing composite UAV is equipped with a fixed-pitch propeller at the front and rear of the middle of the wings on both sides to provide the lift required for vertical take-off and landing and a propulsion propeller at the tail of the fuselage to provide thrust for the cruise phase of level flight. In the cruise phase of level flight, the four propellers at the wing position will be stopped and fixed at least resistance, thereby reducing the resistance in level flight. The hybrid configuration considers the vertical take-off and landing performance of a multi-rotor aircraft and the high-efficiency characteristics of a fixed-wing aircraft. Compared with the tilt-rotor configuration, the hybrid configuration has a simple structure and no tilting components. Secondly, the coexistence of the fixed-wing and the rotor structure is a compromise. The two will affect each other.
On the one hand, the structural mass is significant. On the other hand, the efficiency is limited. In the vertical take-off and landing stage, the wing's large area will increase the take-off and landing resistance. ; In the level flight phase, the rotor will increase the drag. The propeller can be stopped and fixed in position during the level flight phase to balance this effect.
2.3.2 "Agile First" Project-2020 U.S. military vigorously promotes the militarization of eVTOL
The U.S. Army's "Agile First" project promotes the transformation of commercial electric vertical take-off and landing technology to the military field. In February 2020, the U.S. Air Force launched the "Agility Prime" project to explore the feasibility of the aviation industry's emerging electric vertical take-off and landing (eVTOL) technology in special operations, rescue search, short-distance transportation, and other military missions. Nature, and promote the transformation of commercial technology into the military field. It is expected that the airworthiness certification of aircraft will be completed in 2023, and the level of large-scale application will be achieved in early 2025, and large-scale procurement will be realized.
The "Agility First" project named the military electric vertical take-off and landing aircraft as an adaptive support aircraft (ORB). The technical requirements that should be met mainly include the following five aspects:
1) The mechanical structure is simplified compared with traditional vertical take-off and landing aircraft, thereby reducing maintenance costs and cycles;
2) Apply autonomous flight technology to improve safety and reduce operational requirements of personnel;
3) Economical, can be mass-produced and applied;
4) Using distributed electric propulsion technology to achieve low noise;
5) Flexible and agile, reducing dependence on infrastructure.
Correspondingly, the technical elements that the aircraft should possess include:
1) Adopt a distributed propulsion system;
2) Adopt an electric propulsion system;
3) Manned driving, or remote control driving, or autonomous flight;
4) Vertical take-off and landing;
5) Have the ability to hover;
6) It can have a lifting surface;
7) Modular design.
Compared with the electric vertical take-off and landing aircraft in the commercial field, the technical requirements put forward by "Agility First" are somewhat different. For the above-mentioned first type of application scenarios, the technical indicators proposed by Agile Supreme are higher than the existing typical commercial, technical indicators. For example, the Nexus 4EX commercial aircraft submitted by Bell in January 2020 has a range of 95km, while Hyundai's S-A1 The planned content is also about 100km, which can meet the typical commercial urban air transport requirements, but cannot meet the needs of military missions. The application scenarios of the second and third types of aircraft in the commercial field have not yet been highlighted, so they have not received widespread attention. Also, military missions' environmental conditions are significantly different from those of cities, and various ecological control issues such as icing protection need to be considered. The U.S. Air Force stated that the aircraft model purchased will not be customized for military use but will be the same model as the commercial market version.
The total investment in the first phase of the "Agile First" project far exceeds the budget. Many emerging eVTOL commercial enterprises have participated, and Joby and Beta have entered the test flight phase. The U.S. Air Force's venture capital for the "Agile First" project focuses on autonomous flight control, advanced materials and manufacturing processes, acoustics, and collision avoidance systems. The Agile First project has begun signing contracts with participants. ) Won a minor business innovation research contract worth US$3.25 million. The first phase's total planned investment is 10 million U.S. dollars, and the current investment has dramatically exceeded the original plan. Up to now, Joby and Beta have won the bid for the flight test phase.