Trung Quốc Discovers ‘Secret’ Laser Defense Against Hypersonic Missiles
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A group of engineers and aerospace scientists from Beijing, China, has made a groundbreaking discovery in the field of hypersonic missile defense. Through rigorous testing in a wind tunnel, the team found that a laser beam can effectively damage the protective coating on the surface of these high-speed missiles. This discovery has significant implications for China’s development of hypersonic weapons, giving them a distinct advantage over potential threats.
Power Density and Coating Erosion
When the power density of the laser hits 1 kW/cm2, it causes significant erosion of the missile’s protective coating. This specialized coating plays a crucial role in maintaining stability and preventing overheating or structural damage during flight. However, when the power density of the laser beam is doubled, the extent of coating erosion actually decreases.
The research team explained that under the influence of hypersonic airflow, the protective coating suffers more damage when exposed to lower-power-density laser beams. These findings were documented in a peer-reviewed article published in the Chinese academic journal, Physics of Gases.
The Role of Airflow and Laser Feasibility
The use of lasers as a means to counter hypersonic weapons is an ongoing topic of debate. Proponents argue that lasers have low operating costs and can move at speeds close to that of light in the atmosphere, making them an effective defense against hypersonic threats.
However, opponents claim that current laser technology lacks the necessary power and range to effectively neutralize hypersonic missiles within limited time frames. They also emphasize that previous research often failed to accurately simulate real-life atmospheric conditions, where airflow always acts as a cooling agent.
The current study conducted by Lin Jian’s team at the Chinese Aerospace Science and Technology Corporation (CASC), the country’s largest aerospace and defense contractor, sheds light on these concerns. The team found that the destruction of missile materials by laser beams alters the gas flow field and associated mechanisms.
Complex Flow Structures and Challenges
In recent wind tunnel experiments, the researchers discovered that laser-induced material vaporization in a Mach 6 airflow creates a highly complex, turbulent flow structure resembling droplet-like shock waves on the surface of the flying object.
Under the impact of a high-power-density laser beam (2 kW/cm2), the protective coating can be burnt away within a second, leading to subsequent damage to the underlying metal material through combustion.
Conversely, at lower power densities (1 kW/cm2), laser beams do not cause any significant damage to the underlying metal layer, but the coating erosion becomes more pronounced due to energy diffusion.
Traditional wisdom suggests that the protective coating on hypersonic weapons can withstand temperatures of up to thousands of degrees Celsius, making them resistant to laser attacks. However, the research team found that when hypersonic missiles travel at high speeds, the hot air generated during flight contributes to the rapid erosion of the front-facing coating.
This newfound understanding allows for the expansion of laser-based offensive strategies to target not only the fuselage but also the coating of hypersonic weapons.
Laser Power and Future Challenges
In a 2020 experiment conducted by the US military, it took a 150 kW laser system 15 seconds to shoot down a slow-moving unmanned aircraft. During that time, a hypersonic missile could travel at least 30 km, making laser defense against such missiles more challenging.
Scientists estimate that current megawatt-class laser weapons in the US can only create bright spots on targets, achieving a power density of hundreds of watts per square centimeter. To effectively damage targets at long distances, laser power may need to reach the gigawatt level.
Even if future laser weapons achieve this power density, researchers and engineers working on hypersonic weaponry can mitigate risks by improving coating materials or designing missiles with rotating bodies to withstand laser attacks.
The recent findings present a significant breakthrough in China’s hypersonic missile defense capabilities. As research and development in this field continue, laser technology may play a crucial role in countering the threats posed by hypersonic weapons.