On April 10, 1963, the Thresher naval submarine was declared missing, prompting expressions of sympathy from around the world.
Later, it would be discovered that one hundred and twenty-nine men died that day, enshrining a tomb approximately 220 miles off the coast of Boston, Massachusetts.
Advanced Technology and Fateful Mission
The Thresher was the lead ship of the world’s most advanced class of nuclear-powered attack submarines built by the Portsmouth Naval Shipyard.
This submarine was the pride of the Navy’s arsenal with its highly engineered sonar equipment and fire-control capabilities, designed to operate deeper and more silently than her predecessors to avoid enemy detection.
Catastrophic Events Unfold
On April 9th, the USS Thresher set out to conduct sea trials. The next morning, a deep-dive test to explore the limits of Thresher’s abilities began.
Her prior record, with forty trips descending to the maximum operating depth, would be broken that day when the Thresher did not return to the surface.
Attempts to investigate were made with the Trieste, a deep-diving research bathyscaphe, but proved to be unsuccessful. The USS Thresher was the first nuclear submarine to be lost and marked the worst disaster in US Naval history.
Investigation Reveals Tragic Cause
The Navy believed a flooding incident caused the nuclear reactor shutdown on the submarine. During an attempt to resurface from a depth of 1,300 feet, the crew encountered Venturi cooling, causing moisture to freeze in the reducing valve strainers, obstructing compressed air flow needed to blow the ballast tanks.
These strainers, meant to protect valves, ultimately led to the Thresher’s inability to resurface, or restart its reactor, resulting in its collapse and implosion.
The SUBSAFE program was created two months after the accident and responsible for a meticulous series of inspections with the design, manufacturing, and maintenance processes of its nuclear submarine fleet.
Since the program, there has not been a single loss of a SUBSAFE-certified submarine.
Building a Legacy
Local memorials honoring the men include a monument dedicated on April 7, 2013, in Kittery, Maine. The statue displays the men’s names, a bronze replica of the Thresher submarine and is located near the town hall.
A 129-foot flagpole towers nearby at the traffic circle representing a foot for each soul lost.
The USS Thresher National Commemorative Monument was dedicated at the Arlington National Cemetery in Washington, D.C. in September 2019 and was the result of spearheading by local politicians and Naval base administration.
Preserving the Memories
The Thresher Base Association was founded on November 15, 1989, in Portsmouth, NH, to continue to preserve the memory and honor the men and families that were left behind. They also collaborate with and support the mission of the Portsmouth Naval Shipyard.
The group hosts the annual USS Thresher Memorial Service, which will be held this Saturday, April 13, 2024, at the Robert W. Traip Academy.
The memorial service will begin at 1:00pm and will include historical displays, speeches, and music, as well as a wreath-laying ceremony and a 21-gun salute. Consider attending to celebrate their legacy and honor their sacrifice to our country.
You can visit their website for more information: https://www.thresherbase.org
Image credits Naval Sea Systems Command and Arlington National Cemetery
