The Navy recently commissioned the Virginia-class attack submarine USS Oregon (SSN-793) and also completed a refit of the guided-missile submarine USS Michigan (SSGN-727).

SSN-793 was commissioned at a traditional ceremony held at Naval Submarine Base New London, Conn. on May 28, the first regular ceremony of its type since February 2019 due to the COVID-19 pandemic. 

The Oregon was built by General Dynamics’ [GD] Electric Boat division in Groton, Conn. The vessel was previously christened at the Groton shipyard in October 2019.

Electric Boat delivered SSN-793 to the Navy in February (Defense Daily, March 1).

SSN-793 is the second Block IV Virginia-class boat. That variant includes design changes meant to reduce total ownership cost of the submarine. Incorporating these smaller-scale design changes to increase component-level lifecycle of the submarine, the Navy seeks to increase the time between depot maintenance availabilities and increase the number of deployments per vessel.

The Navy said while Blocks I-III Virginia-class submarines are expected to undergo four depot maintenance availabilities and 14 deployments, Block IV vessels are planned to have only three depot maintenance availabilities and up to 15 deployments.

Separately, the Navy completed an extended refit period of the Ohio-class guided-missile submarine USS Michigan (SSGN-727) at the Puget Sound Naval Shipyard and Intermediate Maintenance Facility and the ship got underway on May 27.

The Ohio-class guided-missile submarine USS Michigan (SSGN-727) arrives in Busan for a regularly scheduled port visit in 2017. (U.S. Navy photo by Mass Communication Specialist 2nd Class Jermaine Ralliford)
The Ohio-class guided-missile submarine USS Michigan (SSGN-727) arrives in Busan for a regularly scheduled port visit in 2017. (U.S. Navy photo by Mass Communication Specialist 2nd Class Jermaine Ralliford)

SSGN-727 first entered dry dock in July 2019, four months before the first COVID-19 cases were confirmed.

There are four Ohio-class SSGNs, which are nuclear-armed submarines converted to conventional cruise missile roles. Each submarine can field up to 154 Tomahawk missiles. 

The SSGNs are expected to retire between fiscal years 2026 and 2028, but Navy officials recently said the service is examining the possibility of extending the vessels while the Navy waits for more SSNs with the Virginia Payload Module (VPM) to be built. The VPM increases the number of cruise missiles each attack submarine can hold from the current 27 to about 65. Twenty-two VPM-equipped SSNs will equal the four-ship SSGN fleet (Defense Daily, May 16).

Ohio-class submarines were originally expected to last for 30 years, but were previously extended to 42-year service lives. 

Melissa Kittrell, assistant project superintendent on the USS Michigan project, Code 392, Operations Department said this team was the first to try out new equipment, saving time in maintenance compared to the original work timeline.

“We were the first availability to try out new equipment developed by (Naval Undersea Warfare Center) Keyport,” she said. “This allowed the project to more efficiently conduct some repair work, and saved two weeks to the project timeline.”

Kittrell underscored the amount of work the maintenance team was able to do despite the pandemic.