At present, the research on stealth combat mainly focuses on how to give full play to the stealth advantage, covertly send one's own strength to the confrontation environment, and then launch a surprise attack before the enemy to increase the probability of victory. Air combat platforms have obvious combat advantages over ground, surface and underwater strike platforms, which also makes the stealth capability of air combat platforms more important and becomes a strategic capability that affects the direction of the battle situation.

  In recent years, with the development of intelligent and independent technologies, some people believe that the focus of the future air stealth combat platform is not to achieve surprise attacks based on absolute speed, but to gain air control advantages based on the integrated application of artificial intelligence, cluster tactics and miniaturized autonomous systems. This change will not only reshape the air combat style, but will also profoundly affect future combat forms.

  Stealth technology has limited effectiveness

  The air stealth combat platform is not really stealth, but by reducing the platform's electromagnetic, optical and acoustic detectable physical characteristics, it prevents enemy radar and other air defense detection systems from discovering their traces at the first time. Therefore, the stealth of the air stealth combat platform is a comprehensive result, and its stealth design mainly includes two aspects. In terms of signal characteristics, the source radiation is reduced, such as radar signals, infrared signals and acoustic signals, and thus the interception probability is reduced; in terms of external characteristics, the body structure and appearance design are optimized, the visual characteristics of the body are weakened, and then the observability is reduced. Judging from the existing air platforms of many countries, stealth technology is mainly used in fifth-generation aircraft, such as fighter jets such as the US F-22, F-35 and Russian Su-57, as well as some air-to-air missile systems.

  The stealth design of fifth-generation aircraft is mainly aimed at radar detection. By reducing the radar scattering cross-section, reducing the amount of electromagnetic backscattering, and improving the reverse detection capability. The main stealth design elements used on the fifth-generation aircraft currently include radar wave absorbing materials, exhaust pipe layout, continuous curved design and conformal fuel tank. At the same time, the radar and communication systems of fifth-generation aircraft are also an important part of affecting the anti-detection performance. For example, the US F-35 fighter is equipped with low interception probability radar and communication systems, which can conduct combat operations invisibly; the Russian Su-57 fighter adopts a multihedral gem-shaped structure, and without affecting combat performance, the fuselage is 70% covered with wave-transmitting composite materials that can absorb radar waves.

  Stealth technology is also used in the design of air-to-air missiles. For example, the appearance design of the US military's AGM-158 series joint air-ground missiles has been added to the shape design, including the integrated aerodynamic/stealth design, the use of absorbent materials and coatings, and the increase in the missile's range allows the carrier to strike targets at a long distance while ensuring its own safety.

  Judging from its performance on the battlefield in recent years, fifth-generation aircraft cannot "moving freely" on the battlefield. On the one hand, due to the inherent defects of large combat platforms, it is difficult for fifth-generation aircraft to "completely disappear on the opponent's radar screen"; on the other hand, when facing advanced radar detection, fifth-generation aircraft still needs electronic warfare platforms to support combat. A common practice is to combine fifth-generation aircraft with electronic warfare aircraft to suppress opponents’ radar detection and improve their own battlefield survivability. After the US F-35 fighter jets penetrate deep into opponent's airspace, they need to use airborne active electronic scanning array radar to suppress the opponent's radar system. During this period, the probability that the F-35 fighter backscattered signals were captured by the opponent's radar still exists, and electronic warfare aircraft needed to assist in the operation. In order to consider the strength of the aircraft's structural strength, the Russian Su-57 fighter did not use a stealth coating, which led to an increase in the radar scattering cross-section of the aircraft. In penetration combat, electronic warfare platforms are needed to suppress the enemy radar detection signals.

  Air combat needs technological innovation

  Modern theory of air stealth combat has proposed two methods of raiding the enemy. When attacking at close range, conventional fighter jets such as fourth-generation aircraft are used to fly invisibly with the help of undulating terrain such as hills, or fly at low altitudes at sea level to approach and strike targets; when attacking at long range, fifth-generation aircraft are used to launch attacks on targets from outside the defense zone. Although the latter method is in line with the modern air combat theory of the combat concept of fifth-generation aircraft, that is, to carry out attack operations outside the zone from higher and farther locations, it will expose the fifth-generation aircraft to the detection of the opponent's high-altitude radar in the real confrontation environment. The reason is that although the design of the fifth-generation aircraft incorporates a lot of stealth technology, it is impossible to avoid the inherent characteristics of large air platforms. In addition, the fifth-generation aircraft requires support from electronic warfare aircraft, which, as a huge radiation source, is very easy to be hit by the opponent's key attacks. Therefore, some people believe that the stealth combat capability of fifth-generation aircraft is facing a test in modern warfare. In response, the US military proposed to change the traditional manned stealth combat style, develop higher-efficiency and smaller unmanned offensive combat forces, and maintain considerable aerial combat capabilities. At the same time, it is necessary to develop artificial intelligence, miniaturized air platforms and cluster tactics.

  After the air platform is miniaturized, its radar scattering cross-section can be further reduced to ensure combat concealment. Cluster tactics can use lower-cost missiles or drones to attack more strategically valuable targets, such as large and medium-sized destroyers, aircraft carriers, and air defense and anti-missile positions. At the same time, cluster tactics can also form saturated attacks on targets, consume enemy air defense firepower, and effectively cover their own human-machine operations. Under the influence of artificial intelligence, cluster operations and platform miniaturization, the US military also proposed the concept of multi-domain warfare in defense zones. That is, multiple drones form offensive forces, dispatch from the opponent's defense zone, and carry out coordinated operations, with the purpose of increasing the difficulty of the opponent's air identification and reducing the effectiveness of its countermeasures. During this period, the cooperation of the manned/unmanned platform can avoid premature exposure of high-value targets. In addition, the raid mainly relies on offensive forces composed of drones, which all contribute to the development of stealth combat in the air.

  The effectiveness of actual combat remains to be seen

  A large number of military practices in recent years have shown that the effectiveness of offensive operations still depends on the suddenness, concealment and sustainability of the assault operations, especially air combat for air superiority. Therefore, using an air stealth combat platform to carry out raids is still an effective means generally recognized by all countries. At the same time, with the massive use of drones in regional conflicts, countries are also rethinking and designing future stealth operations. At present, in some local conflicts, the style of coordinated combat between fifth-generation aircraft and drones has appeared. Although the development is slow, this trend is worth paying attention to.

  Judging from the actual situation, the formation of air assault forces based on artificial intelligence, cluster tactics and miniaturized autonomous systems, especially the coordinated implementation of operations with/drones is still in the exploration stage, and their actual combat effectiveness remains to be seen. According to the concept of conflicts in hot spots in the field of military research, in a specific geographical environment and in the face of a complex electromagnetic environment, new combat concepts and technological breakthroughs are needed to achieve large-scale air combat and fire strikes in one/unmanned clusters, and fully verified. Especially with the increase in the types and numbers of drones, integrating them into a unified command and control network is not easy. In order to truly form practical capabilities, there are still many difficulties in technical fields such as communication links, data processing, and distributed control.

[Editor in charge: Gao Qiang]