“The Navy replaced the guns with four large missile tubes each capable of holding three of the hypersonic missiles apiece,” Zumwalt-class program manager, Capt. Clint Lawler, explaining the physical change that was underway in the guts of the Navy most unconventional design destroyer.
That shift in hardware is significant since the ability to locate first and attack at a greater range, with less information and less warning, becomes the primary factor of the sea control in the Pacific. Hypersonic weapons are not range enhancers they also shorten response time and make it harder to track them defensively due to maneuverability and lower flight paths (as compared to ballistic missiles). What is produced is a surface ship that is not acting as much like a conventional escort in that it is acting as a mobile strike node, i.e. something that can affect sea space far beyond the horizon without necessarily reducing the range.
The most apparent stimulus is the Zumwalt-type shift in a gun-based land-attack model to a blue-water striker. The two 155mm Advanced Gun Systems in the class were abandoned as the Navy abandoned the special ammunition, and instead redesigned the ships with hypersonic launch capability. Zumwalt has now four massive missile tubes that can deploy hypersonic strike weapons, a renovation that necessitated the elimination of both gun mounts and recovery of space deep below decks that could be utilized in the present and future.
These are no small additions to those tubes. They have 87 inch diameter each and the Navy is loading them using an Advanced Payload Module process which will “triple pack” the missiles into each tube. Introducing such architecture yields a simple arithmetic of impressive power: with as many as 12 hypersonic rounds per ship already prioritizing signature minimization and automation. The point here is not to replace all existing missile missions but to introduce a very high-value, very limited effect of a rapid, long-range conventional strike into a portion of the fleet which can move, conceal, and survive.
This operationally puts sea control in another fray. According to the analysis conducted by Congressional Research Service, hypersonic weapons have the potential to tax defenses, as on the ground-based radar is unable to identify hypersonic weapons until the late stages of the weapon flight. Early detection reduces the time inside which commanders and defensive systems can respond, as well as the quantity of potential intercept opportunities. In a Pacific setting that is characterized by distance and the formation of island chains and the presence of widely dispersed forces, the party capable of exerting such a timeline pressure can influence the manner in which the opposing side will move about even without firing a single shot.
Even the ship platform itself is an issue. The Zumwalt class featured an electric propulsion system, and a combat system design that would have allowed the ship to be automatized to a large degree, a feature that would have enabled it to carry a smaller crew than similarly sized surface combatants. In actual practice, that mix enables sustained operations with less staffing requirements and also provides space, electrical, computational, and physical, to allow modernization cycles which are currently being used up by hypersonic integration.
The conversion is also being treated as a template. USS Zumwalt returned to sea after the refit work, with the yard calling the effort “a pivotal milestone” that would “set a precedent for the Zumwalt class,” while the other ships follow on parallel paths. USS Lyndon B. Johnson is undergoing combat system activation and tube installation, and USS Michael Monsoor is scheduled to receive the same Conventional Prompt Strike integration sequence.
The more significant transformation, in the long term, is that a destroyer can launch a new missile, rather than that a stealth-leaning surface combatant is being turned into a high impact strike weapon of small number. Should the problem of sea control in the Pacific cease to be based upon the dense formations and become more of the dispersed platforms capable of striking rapidly at a great distance, then the hypersonic ships of the Navy will become a lever, one that turns where surface forces can act, and where an opponent must assume that they can do it with any patch of ocean.
