USS Zumwalt is Losing its Iconic Cannon

The U.S. Navy's futuristic Zumwalt-class destroyers were built to carry twin high-velocity cannons for shore bombardment, like a modernized, stealthier version of a battleship. The cannons were installed, but after the number of vessels in the class was radically cut back from 32 to three, the cost per round of manufacturing the ammunition rose to an impractical $800,000-$1 million per shot. The production run of ammunition was canceled, and the guns are functionally unusable - but the Navy has other things in mind for the Zumwalts. Soon, half the cannons will come off and the ships will field the Conventional Prompt Strike hypersonic missile system. 

First-in-class USS Zumwalt is first in line for the modification, and her forward cannon has been removed, photos from her crew's Facebook page show. In its place, USS Zumwalt will carry four all-up round canisters, each containing three hypersonic missiles. This will add a dozen of the hard-to-stop hypersonic maneuvering missiles to her more conventional arsenal of 80 vertical launch cells.

Adding hypersonic missiles to the Zumwalt-class will not be cheap. Lockheed Martin, which is carrying out the work for the Navy, secured a contract worth $1.1-2.0 billion for the project (over all three vessels in the class). This covers removal of the forward gun and replacement with four extra-large missile cells; however, the second gun just forward of the deckhouse will remain in place for an indeterminate period. 

USS Zumwalt departs Bath Iron Works, 2016 (USN file image)

USS Zumwalt (foreground) and USS Michael Monsoor in San Diego (File image courtesy USN)

Huntington Ingalls is carrying out the first modification on USS Zumwalt at Ingalls Shipbuilding, and second-in-class USS Michael Monsoor will be next. Bath Iron Works - the original home of the class - will perform Monsoor's refit.

Conventional Prompt Strike is the Navy's version of a joint hypsersonic weapons program, shared with the U.S. Army and U.S. Strategic Command. The Navy's version will be fielded on the Zumwalts first, and will be installed on the Block V Virginia-class attack sub when it begins to deliver in the 2030s. Strategic Command sees it as a "highly lethal platform" that will send a "strong deterrence message to our adversaries."

"The Navy / Industry team is moving with a sense of urgency to integrate CPS capability into USS Zumwalt," said Rear Adm. Tom Anderson, Program Executive Officer (PEO), Ships. "Many steps have been taken and are on track to get this important player on the field on time."