A seamount ‘strike’ nearly crippled a $3 billion Navy ‘Seawolf’ submarine

Originally published by The National Interest

In October 2021, the USS Connecticut, a $3 billion Seawolf-class submarine, collided with an uncharted seamount in the Pacific Ocean. The incident, which injured eleven crew members, was attributed to navigational failures and poor risk management.

-Despite its advanced technology, the submarine was severely damaged and struggled to ascend. The official investigation criticized errors in navigation planning, watchteam execution, and risk management, stating that better decision-making could have prevented the grounding.

-The USS Connecticut has since become a case study in improving U.S. Navy protocols, especially in the face of increasing tensions in the South China Sea.

USS Connecticut’s Crash in the Pacific: A Costly Navigation Error

A few years back, the U.S. Navy released its highly anticipated report covering the investigation into the USS Connecticut’s collision with an ‘underwater’ mountain in October 2021.

The Seawolf-class submarine hit an uncharted seamount while sailing in the Pacific, causing an extensive amount of damage to the vessel.

While the submarine was able to power its way to a U.S. Navy base positioned in Guam following the collision, eleven crewmembers were injured in the incident. An “uncharted seamount” was also deemed responsible for a similar type of collision back in 2005.

According to the National Oceanic and Atmospheric Administration, an estimated 100,000 seamounts could rise more than 3,000 feet from the seafloor.

What the report says

As detailed in the official report, the incident “resulted from an accumulation of errors and omissions in navigation planning, watchteam execution, and risk management that fell far below U.S. Navy standards … Prudent decision-making and adherence to required procedures in any of these three areas could have prevented the grounding.”

Stars and Stripes also notes that prior to the crash, “At least one sailor detected sonar readings that were not matching the navigational chart of the undersea area. However, the officer of the deck did not report the hazard to the Connecticut’s commanding officer, who was not standing duty at the time.”

Essentially, the USS Connecticut’s crash can be considered an example of the swiss cheese model, which explains how inconstant weaknesses (or holes) can align and cause catastrophic damage that would otherwise be prevented.

Since the USS Connecticut is often referred to as the “luxury sports car” of underwater vessels, the collision was particularly noteworthy. The $3 billion-dollar Seawolf-class submarine is fitted with the most sophisticated technology, however, it was unable to properly ascend toward the surface for 11 minutes, according to the investigation. At a depth of 74 feet and increasing, the chief of the watch “restored the trim pumps by pumping from one vented auxiliary tank to another.”

The report added that “With the system restored, he commenced deballasting and pumped approximately 100,000 pounds of water overboard.”

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