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. However, according to Rick Connole, the son of the Trigger’s final commanding officer, David Connole, there is an easy explanation for why someone mixed up the sub pieces between vessels.
“They swapped parts all the time in construction,” Connole told Popular Science after reading an earlier version of this article.
Archival images further underscore how workers shared components between the Gato-class subs. In one picture dated July 1, 1941, a mid-construction Silversides and Trigger are seen just inches apart from one another in the Mare Island Navy Yard.
The U.S. Navy honored many of its fallen ships after WWII by naming its newer, Tang-class subs after them. These included a Tang-class Trigger, which Rick Connole’s mother christened herself prior to its launch in 1951. The Connole family later received another dedication in the form of the USS Connole, a Knox-class frigate, in 1968.
Taken altogether, the latest Trigger discovery and its descendent vessels serve as poignant reminders that while many ships and their crews ultimately returned home following WWii, many did not.
Update 8/12/2026 2:00 p.m. EDT: This article has been updated to include information and quotes from Rick Connole.
