JUST IN: Report Casts Doubt on Value of Hypersonic Weapons

Defense Dept. image

ARLINGTON, Virginia — Limited tactical uses and unsolved technological challenges of designing hypersonic weapons raise questions about whether the weapons are worth the cost, said a new Congressional Budget Office report.

“U.S. Hypersonic Weapons and Alternatives,” released Jan. 31, analyzed the hypersonic weapons being developed by the U.S. military and compared them with existing or potential weapons — such as ballistic missiles — that might fill similar roles for a fraction of the price.

Hypersonic weapons are distinguished from conventional strike weapons by a combination of long range, high speed and maneuverability. Hypersonic missiles are considered a possible counter to the anti-access and area-denial systems that potential adversaries such as China and Russia are deploying to prevent U.S. forces from operating freely in their regions, the report stated.

In theory, hypersonic weapons could be launched from outside the range of those systems and could reach targets within minutes over medium to intermediate ranges — from hundreds to a few thousands of kilometers — with a high degree of accuracy and less vulnerability to defenses than existing missiles, the report said.

However, flying faster than Mach 5 in the Earth’s atmosphere generates extreme temperatures and creates what the report called the “fundamental” technological challenge for hypersonics: heat management.

Shielding sensitive electronics from temperatures as high as 3,000 degrees Fahrenheit is a problem that has yet to be solved, the report said.

The thermal challenges presented with hypersonic development affect communications, targeting and scramjet technology — which involves designing engine components that can maintain air-fuel mixing at the right temperature, air pressure and density. The report stated the challenge has been likened to keeping a match lit in a hurricane.

In examining how both hypersonic and ballistic missiles held up to potential adversaries’ anti-access zones, both were well-suited, the report concluded. Both missiles equipped with maneuverable warheads could provide the combination of speed, accuracy, range and survivability — the ability to reach a target without being intercepted.

Hypersonic missiles are not necessarily more survivable than ballistic in a conflict unless the conflict involves “highly-effective long-range defenses,” the report found. Hypersonic missiles can neutralize long-range defenses because they fly inside the atmosphere, below the altitude where midcourse ballistic missile defenses typically operate.

“Only very effective long-range defenses would be likely to threaten ballistic missiles in midcourse,” the report reads “To date, no potential U.S. adversaries have deployed such defenses.”

When comparing possible alternatives, the CBO considered scenarios involving China and Russia, both of which have long-range systems tailored to prevent the United States from air, land and sea superiority during a conflict.

The report stated that by spending much of their flight inside the atmosphere, hypersonic boost-glide missiles would have an advantage over ballistic missiles in surviving midcourse ballistic missile defense systems, which aim to intercept ballistic missiles in the middle of flight while high above the atmosphere on a predictable and detectable path.

That potential advantage for hypersonic boost-glide missiles might become important if a potential U.S. adversary developed midcourse ballistic missile defenses that operated outside the atmosphere and that were effective against countermeasures such as decoys to fool interceptor missiles, the report said.

Against shorter-range missiles, the advantage is less clear, the report stated.

The report found a limited number of scenarios where hypersonic missiles were distinctly useful over ballistic missiles, noting the procurement cost of hypersonic missiles is roughly one-third greater than the cost of ballistic missiles of the same range with maneuverable warheads. The report estimated that acquiring 300 ground-or-sea launched ballistic missiles over 20 years would cost $13.4 billion, compared to $17.9 billion for comparable hypersonic missiles.

The Defense Department is taking a phased approach to hypersonic technology and has spent more than $8 billion since 2019 on programs to develop hypersonic missiles, the report stated. Programs have included separate efforts by the Army, Navy, and Air Force, collaborations among DARPA, the Air Force and the Navy and various research programs for missile components.

Given the cost, the report suggested hypersonic weapons’ usefulness to be “niche” when compared to the capabilities of ballistic missiles, mainly useful to address threats that were both well-defended and extremely time-sensitive.

Hypersonic missiles also have an advantage against systems designed specifically to intercept ballistic missiles, the report found.

“Indeed, a main reason that China and Russia have been developing hypersonic weapons is a desire to defeat the United States’ comparatively advanced ballistic missile defense capabilities,” the report read.

Realizing the full potential of hypersonic weapons hinges on the success of future research and development, the report concluded.

Topics: Strategic Weapons