The Hypersonic Missile Advantage

In contrast to aircraft and subsonic missiles, the Navy’s hypersonic Conventional Prompt Strike (CPS) missile reaches a 2,200 nautical mile distant target in 30 minutes.

The latest version of the subsonic Tomahawk cruise missile has a range of 900 nautical miles; the F/A-18 and F-35C have 444 and 600 nautical mile ranges, respectively. An attack by carrier attack aircraft involves a time-consuming launch sequence, midair refueling, and hours aloft to reach its target. The subsonic Tomahawk launches quicker but requires close to 2 hours to reach a 900 nautical mile distant target.

Currently, hypersonic missiles consist of two components: the booster and the glide vehicle. After accelerating to hypersonic speed (a mile a second or greater), the booster separates from the glide vehicle and falls away. The glide vehicle then flies unpowered to the target. During its atmospheric descent, the glide vehicle becomes extremely hot and, upon impact, causes destruction and fires.

Who has the lead in hypersonic missiles?

In the early 21st century, the Chinese and Russians focused on developing hypersonic missile technology, while the United States concentrated on disarmament treaties.

The Chinese currently boast about their DF-21 ‘carrier killer’ missile with a range of 1,100 nautical miles. Additionally, the Chinese have developed and deployed a series of hypersonic missiles: the DF-17 (medium range), the DF-27 (anti-ship missile), and the DF-41 (intercontinental range).

If America does not vigorously pursue its hypersonic missile program, China could seize the initiative by arming its fleet with hypersonic missiles and threaten America’s naval superiority. The United States Navy could find itself out-ranged in a battle against long-range Chinese hypersonic missiles in a conflict.

Initially, the Navy considered deploying the Conventional Prompt Strike (CPS) hypersonic missile on the four Ohio-class SSGN submarines. However, their cost and age caused the Navy to drop these boats from consideration.

The Navy’s current plan for mounting hypersonic missiles on warships has two phases: The first involves the conversion of the three Zumwalt-class destroyers to deploy six missiles per ship for a total of 18 hypersonic missiles. The second phase will utilize the Virginia Payload Module (VPM) to equip Block 5 and Block 6 Virginia-class submarines with either 28 subsonic Tomahawk missiles or 12 larger CPS hypersonic missiles.   

The Navy’s plan will guarantee its inferiority vis-à-vis China. First, the tiny surface component (18 missiles) is inadequate compared to the ever-growing threat of the Chinese Navy. Second, to equal the 608 currently deployed Ohio-class SSGN subsonic missiles, the plan requires the construction of 20 Block 5 and 6 Virginia-class submarines starting in the 2020s and ending in 2044. By 2044, the Navy would deploy either 560 subsonic missiles or 240 CPS hypersonic missiles.

If the Navy pursues its current missile deployment strategy, it will face a significant deployed missile shortfall in the 2030s, deploying only 62 percent of today’s missile capacity.  

The United States Navy has seen its active ship count decline from 594 in 1987 (the Reagan era build-up) to the current 295 ship level.

Although there is talk of expanding the fleet to 350 ships, America’s shipyards are: hampered by skilled labor shortages, already loaded to capacity, and straining to meet schedule and cost commitments.

Historically, the United States Navy has repurposed warships that are no longer needed as platforms for introducing new types of weapons into the fleet.

In the 1950s and 1960s, the Navy removed 6-inch and 8-inch turrets from World War II-era cruisers, installed Tarter and Talos missiles, and repurposed nine ships as guided missile cruisers.

During the first decade of the 21^st century, the Navy modified four Trident-carrying Ohio-class SSBNs into Tomahawk-equipped SSGNs.

As the Columbia-class SSBNs join the fleet, the Ohio-class SSBNs will become candidates for scrapping. If the Navy modified all 14 Ohio-class SSBNs to CPS-equipped SSGNs, each carrying 66 hypersonic missiles, America would deploy an additional 924 hypersonic missiles.

With refueling, an Ohio-class SSBN to SSGN conversion cost 4 billion dollars per boat in the early 21^st century. With inflation, the cost should rise to 5 billion per boat or 70 billion dollars for the entire class conversion. 

Current plans call for retiring a Nimitz-class carrier with the commissioning of each Ford-class carrier.

By installing 100 missile launch tubes in the ship’s flight deck, a repurposed Nimitz-class carrier would carry 300 CPS hypersonic missiles. Utilizing the flight deck and hangar space, the ship could carry twice an Arleigh Burke destroyer’s complement of defensive missiles and anti-submarine helicopters.

Repurposing would require the deactivation or removal of the catapults, elevators, ammunition management, take-off and landing systems, and arresting cables. Additionally, the repurposing will need to either rebuild the island or install a DDG-125 Flight III destroyer equivalent superstructure. With reactor refueling, the repurposing should cost 7 billion dollars per ship or 70 billion dollars for the entire class.

A repurposed Nimitz-class aircraft carrier and an Ohio-class submarine will have 50 and 40-year-old nuclear reactors, respectively. Responding to the electric power demands of artificial intelligence and electric vehicles, civilian operators are relicensing older commercial nuclear reactors. Similarly, a Navy nuclear reactor life-extension program could extend the lives of the repurposed ships and submarines by decades.

The development price of $41 million per CPS missile should fall with volume production to 10 million dollars per missile. Purchasing 7,848 missiles for the repurposed ships (one spare for each loaded tube) would cost 78 billion dollars.

Repurposing 24 warships with 7,848 missiles would cost 218 billion dollars. Spread over 15 years, the annualized cost would equal 14.5 billion dollars.

A repurposed Ohio-class submarine should require a crew of 155, the same as the current Ohio-class SSGN.

A Nimitz-class hypersonic missile carrier with 100 CPS and 200 defensive launch tubes would need three times the crew complement of an Arleigh Burke destroyer or 1000 sailors.

If it combined its current hypersonic missile deployment plan (18 missiles on 3 Zumwalt destroyers and 240 missiles in 20 VPMs) with those on repurposed vessels (924 missiles on 14 Ohio-class SSBNs and 3,000 missiles on 10 Nimitz-class CVNs), the Navy would eventually deploy 4,182 hypersonic missiles. 

By 2035, the Navy’s currently planned force of 158 CPS missiles will do little to deter the Chinese. However, if the Navy repurposed three Nimitz-class carriers (900 CPS missiles) and four Ohio-class submarines (264 CPS missiles), it would deploy 1,322 CPS missiles, a more credible deterrent.

By the Cold War’s end, the Navy deployed approximately four thousand nuclear warheads in SSBNs. While CPS hypersonic glide vehicles and nuclear warheads are very different weapons, they both must convince an adversary’s leadership that initiating hostile actions will have dire consequences. Like the Cold War’s nuclear weapons, four thousand glide vehicles might deter the Chinese Navy’s expansionary tendencies.

Although the United States has the lead in carrier-based naval airpower and submarines (SSGNs), it must build a powerful shipborne hypersonic missile capability to establish a deterrence triad. Hobbled by skilled labor shortages, the American shipbuilding sector cannot match the output of its Chinese counterpart. Repurposing existing warships is a cost-effective way—perhaps the only way—of increasing the Navy’s active ship count without adding to new ship construction.

The current CPS implementation plan will not provide the Navy with enough hypersonic missiles to deter China’s aggressive expansionary tendencies. To fill the hypersonic missile gap, this paper advocates repurposing soon-to-be retired ships from the Ohio and Nimitz classes into hypersonic missile carriers. Whether the Navy repurposes warships or uses an alternative approach is not critical. What is vital is creating an overwhelming hypersonic missile force that can deter China’s thrusts into the Pacific and Southeast Asia.

Robert (Bob) Purssell is a Massachusetts Institute of Technology graduate, Bob worked in the defense and semiconductor industry first as an engineer and subsequently as an engineering manager. Currently retired, he writes novels and gives talks on military and historical events.

Robert (Bob) Purssell is a Massachusetts Institute of Technology graduate, Bob worked in the defense and semiconductor industry first as an engineer and subsequently as an engineering manager. Currently retired, he writes novels and gives talks on military and historical events.