A U.S. Navy stealth ship is getting a major upgrade: USS Zumwalt is currently being fitted with an experimental hypersonic weapon system called Conventional Prompt Strike.
Hypersonic weapons are seen as the next stage in non-nuclear warfare, as they enable targets to be destroyed swiftly and accurately and from far greater distances than conventional weapons allow. In a briefing document leaked by a former Massachusetts Air National Guard member, it was revealed that China had tested its DF-27 intermediate-range hypersonic weapon system last year, according to AP News.
Hypersonic weapons travel at more than five times the speed of sound, or "Mach 5" — approximately 3,830 mph (6,160 km/h).
Conventional Prompt Strike launches in the same way as a ballistic missile but is then propelled by a hypersonic glider vehicle. The glider vehicle is capable of traveling at up to Mach 8 — approximately 6,140 mph (9,880 km/h). Each of the Zumwalt-class destroyers would be deployed with four weapon tubes, with each tube carrying three Conventional Prompt Strike missiles.
When firing at long range, missiles traveling at hypersonic speeds may be intercepted by advanced defense systems. After detecting an incoming missile, a defense system predicts the flight path and launches an interceptor missile. Hypersonic missiles typically have some maneuverability, making them harder to shoot down, although much of the development focus to date has been on maneuverability for accuracy, rather than for evasion. They generally tend to rely on being too fast for detection systems to react.
The degree of maneuverability also depends on where the missile is in its trajectory. Any object traveling at immense speed is already subject to high forces, including drag from wind resistance. Its own momentum, which keeps it on course, means you would need very high forces to achieve even a small turn. Maneuverability for evasion purposes is not of much benefit; any turn would cause the missile to lose speed, which would make subsequent interception easier.
To overcome some of the drag, hypersonic missiles typically travel at high altitudes of up to 50 miles (80 km) above sea level. For comparison, a typical passenger aircraft has an optimal cruising altitude between 5 and 7 miles (8 and 11 km). To achieve the required speed, hypersonic missiles need to minimize drag, and air density is much lower the higher you go.
The Zumwalt-class destroyers are already equipped with cutting-edge technology, including electric propulsion systems, wave-piercing hull, low radar detectability and automated damage control systems. And with the Conventional Prompt Strike system, it could gain the ability to strike farther than ever before.
