On March 18, 2022, Russia’s use of a hypersonic missile against a Ukrainian arms depot raised alarms about the future of warfare. While this particular application wasn’t groundbreaking, the next generation of hypersonic missiles being developed by Russia, China, and the U.S. presents a significant challenge to global security. A key factor in this concern is the speed at which these missiles can travel and the implications for response times.
As an aerospace engineer specializing in space and defense systems, including hypersonic technology, it’s clear that these systems pose a unique threat due to their maneuverability during flight. Unlike traditional ballistic missiles, their unpredictable flight paths necessitate constant tracking. Furthermore, their operational altitude, higher than subsonic missiles yet lower than intercontinental ballistic missiles (ICBMs), falls within a gap in existing tracking coverage for many nations, including the U.S., Russia, and China.
The Destabilizing Potential of Hypersonic Missiles
The claim that some Russian hypersonic weapons can carry nuclear warheads is deeply concerning. This ambiguity forces potential targets to assess the probability of a conventional versus nuclear payload. In the case of the U.S., a determination that the weapon is nuclear would likely trigger a retaliatory nuclear strike against Russia. The speed of these hypersonic weapons drastically reduces the time available for diplomatic intervention, exacerbating an already precarious situation. It’s this destabilizing influence that constitutes perhaps the most significant risk posed by modern hypersonic missiles. A proactive approach, including the rapid development and deployment of hypersonic weapons by the U.S. and its allies, could compel nations like Russia and China to negotiate a diplomatic framework for managing these advanced weapons.
Defining Hypersonic Speed
Hypersonic speed refers to velocities significantly exceeding the speed of sound. At sea level, this threshold is approximately 761 miles per hour (1,225 kilometers per hour), decreasing to 663 mph (1,067 kph) at an altitude of 35,000 feet (10,668 meters), where commercial airliners typically operate. While passenger jets cruise at speeds approaching 600 mph (966 kph), hypersonic systems achieve velocities of 3,500 mph (5,633 kph) – roughly 1 mile (1.6 kilometers) per second – and beyond.
Hypersonic technology isn’t new. John Glenn’s return to Earth in 1962 during the first U.S. crewed orbital flight involved atmospheric reentry at hypersonic speeds. Moreover, ICBMs within global nuclear arsenals are inherently hypersonic, reaching speeds of around 15,000 mph (24,140 kph), or approximately 4 miles (6.4 km) per second at peak velocity.
ICBMs are launched using powerful rockets, following a predictable trajectory that takes them beyond the atmosphere into space before returning. The new generation of hypersonic missiles, while fast, doesn’t reach the same speeds as ICBMs. They utilize smaller rockets, remaining within the upper layers of the atmosphere.
Diagram illustrating missile trajectories at different altitudes in relation to Earth's atmosphere.
Three Categories of Hypersonic Missiles
There are three primary types of hypersonic weapons, excluding ICBMs: aero-ballistic missiles, glide vehicles, and cruise missiles.
- Aero-ballistic Systems: These missiles are launched from aircraft, accelerated to hypersonic speeds via rocket propulsion, and then follow an unpowered, ballistic trajectory. The Kinzhal missile used by Russia in Ukraine exemplifies this type, representing technology dating back to the 1980s.
Technicians working on a missile beneath a military jet plane.
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Hypersonic Glide Vehicles: These are boosted to high altitudes by a rocket before gliding towards their target, maneuvering throughout their flight. Examples include China’s Dongfeng-17, Russia’s Avangard, and the U.S. Navy’s Conventional Prompt Strike system. Some U.S. officials have voiced concerns about China’s hypersonic glide vehicle technology surpassing that of the U.S.
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Hypersonic Cruise Missiles: These missiles are propelled to hypersonic speeds by a rocket and then maintain that speed using an air-breathing scramjet engine. By ingesting air, they require smaller launch rockets compared to glide vehicles, potentially reducing costs and enabling deployment from a broader range of platforms. Both China and the U.S. are actively developing hypersonic cruise missiles.
The Challenge of Defense
The primary driver behind the development of next-generation hypersonic weapons is their exceptional difficulty to defend against, stemming from their speed, maneuverability, and unpredictable flight paths. The U.S. is pursuing a multi-layered defense strategy involving a network of space-based sensors and close collaboration with allies. However, this approach is likely to be resource-intensive and require considerable time to implement.
Given the ongoing advancements in hypersonic weaponry and defense systems, it’s vital to assess the threat they pose to national security. Hypersonic missiles armed with conventional warheads are best suited for targeting high-value assets, such as aircraft carriers. Neutralizing such a target could significantly alter the course of a major conflict. However, the high cost of hypersonic missiles likely limits their production quantities. As demonstrated by Russia’s recent usage, hypersonic weapons are not a guaranteed path to victory in conflict. In summary, how fast a nuclear missile can travel, especially considering hypersonic technology, is a critical factor shaping modern strategic considerations and defense planning.
