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The World War II submarine USS Silversides is currently receiving its first dry dock preservation work in over 50 years. The thorough review of the famed piece of World War II naval history is often a largely routine effort, but workers recently discovered something entirely unexpected while inspecting the sub: a flood valve stamped with the word “Trigger” alongside the serial number L-792-228.
The component itself is mundane, but its context is remarkable. According to historians, the valve is likely the only surviving piece of the USS Trigger, a similar Gato-class submarine with a much more tragic fate than the Silversides.
Named after the unnervingly toothy triggerfish, the Trigger launched from California’s Mare Island Navy Yard on October 22, 1941. Although initially slated to participate in the Battle of Midway, the sub ran aground northeast of the island before returning to Pearl Harbor on June 9, 1942. The Trigger went on to complete 11 patrols before meeting her fate during the 12th outing. On March 28, 1945, nearby U.S. vessels in the East China Sea overheard Japanese planes and vessels engage in a two-hour attack on a fellow submarine that included a barrage of depth charges. Postwar Japanese records also reported that an aircraft located and bombed a U.S. sub on the same date, followed by eyewitness confirmation of a large oil slick indicative of a successful sinking. After not arriving at Midway Island by May 1, officials reported the Trigger as presumed lost, and her name was stricken from the Naval Vessel Register on July 11.
The Silversides deployed two months before the Trigger, so it’s unclear why the surviving submarine ended up with a flood valve initially intended for the latter vessel—although their components are presumably interchangeable given that both are Gato-class subs. Regardless of the explanation, the discovery serves as a poignant reminder that while many ships and their crews ultimately returned home following WW2, many did not.
The Silversides has been the centerpiece of its own museum in Muskegon, Michigan since 1987. The nearly 312-foot-long Gato-class submarine is now across Lake Michigan for its facelift in Sturgeon Bay, Wisconsin. The $3.5 million dry docking project will finish in October, ensuring the historic submarine remains seaworthy for at least another 15–20 years upon returning to its museum.
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