Editor’s Note: Captain Bryant published a call for declassification of the full record of the investigation into the loss of the Thresher in the July Proceedings. That article lays out the case that time pressures resulting from great power competition may have been a contributing factor in the accident. The Navy is reviewing the records, but no decision on declassification has been announced.
The USS Thresher (SSN-593) imploded 56 years ago on 10 April 1963, killing all 129 people on board, during a time of unequivocal great power competition. In September 1961, Soviet leader Nikita Khrushchev was pictured on the cover of Time magazine saying, “We will bury you!” while the U.S. press and intelligence community were speculating that Soviet intercontinental ballistic missiles were better than their U.S. equivalents.
Did the pressure of great power competition—the pressure to win at technology and capability—contribute to the loss of the Thresher? There are reasons to believe it did; given similar pressures on the Navy today, further study is needed to ensure that such an event does not happen again. The 1963 Naval Court of Inquiry (NCOI) records should have been declassified in 2013, when they were 50 years old, yet we learn after my filing of a Freedom of Information Act (FOIA) request the Navy is only now reviewing the NCOI for declassification.
Later this year, a memorial to the submarine’s crew will be dedicated at Arlington National Cemetery in Virginia, making this a fitting time to reexamine the causes of the loss—if only the data on which the NCOI relied could be made available before that ceremony.
In a partial response to this FOIA request, the U.S. National Archives released a photo essay of pictures from the search for the Thresher in 1963–1964 taken after the NCOI report was completed. These 41 photos are shown in the gallery attached to this article.
Several of the photos tell parts of the story of what happened to the Thresher. The first (Figure 1) attributes the identification of the parts of the wreckage to Portsmouth Naval Shipyard (PNS), which designed and built the first submarine of the new class. The Thresher’s post-shakedown availability (PSA) was conducted at PNS after about a year of operating at sea.
Figure 2 shows the Thresher’s stern section, which is labeled in the photos as the tail section. It shows the stern tube where the shaft and propeller (screw) would be inserted. The upper rudder (vertical), port and starboard horizontal stabilizers, and their respective stern planes are shown as originally built.
During the nine-month-long PSA, a hydrophone array fairing, part of the Passive Underwater Fire Control Feasibility System (PUFFS), was attached to ends of the port and starboard horizontal stabilizers, forward of their respective stern planes. Figure 3 is a photo of USS Pogy (SSN-647)—borrowed from U.S. Submarines since 1945 (Norman Friedman, Naval Institute Press, 1994)—showing what the Thresher’s stern would have looked like, except the Thresher’s screw would have had five blades, not seven.
Figure 4 shows the stern section among the wreckage of Thresher, resting around 8,400 feet below surface of the Atlantic Ocean, about 200 miles east of Cape Cod. The label on the picture indicates the photo was taken by the USNS Mizar (TAGOR-11), a deep-ocean research vessel operated by the Naval Research Laboratory, using a camera mounted on a towed sled. The label says the hole is #7 Main Ballast Tank (MBT) Vent Valve. MBTs are open to the sea on the bottom, and the vent valve on the top of the tank is opened to release the air in the tank to submerge and shut when air is blown into the tank to displace the water to surface the submarine. There is no damage to this area because MBTs and the free flood space behind it are always equalized with sea pressure. The top of #7 MBT Vent Valve is shown in the open (vent position). Notice that by design it is off center line to starboard of the submarine.
Figure 4. The Thresher’s stern section at the bottom of the Atlantic.
Figure 5 is a collage/mosaic comprised of eight pictures of the stern. The pressure hull, made of HY-80 steel, was compressed, along with its supporting frames as they yielded to sea pressure. The Engine Room pressure hull starts just forward of MBT #7.
The previously released conclusions from the NCOI reported that the likely cause of the sinking was continuous flooding from a two- to five-inch hole in a seawater piping system. Such major flooding could have filled the hull, equalizing external and internal pressure across the pressure hull, before it reached crush depth. Had this been the case, there would not have been the implosion whose results are evident in this mosaic.
Figure 6 is a mosaic that is a cropped and enhanced version of Figure 5 above.
The red box in Figure 7 indicates the location of the hull section shown in Figures 5 and 6 relative to the Thresher’s overall configuration. The black lines in Figure 7 show the outline of the pressure hull.
Figure 8 shows the fixed starboard horizontal stabilizer and its corresponding stern plane, which was ripped off the submarine during the violent whipping and twisting when the hull imploded at a calculated depth of 2,400 feet with estimated force equivalent to 22,500 pounds of TNT. This assembly came to rest 100 yards away from the stern section. This is the only photo in this paper that was taken by the Trieste, a Swiss-designed, Italian-built deep-diving research bathyscaphe that once reached the deepest part of the oceans, Challenger Deep in the Mariana Trench. It was acquired by the U.S. Navy and later used in the Thresher search.
The final two pictures (Figures 9 and 10) show the fixed port horizontal stabilizer and its stern plane still attached with its PUFFS fairing. Not visible is the five-bladed screw that should be directly behind the rudder—probably because, if still attached, it is outside the view captured by these pictures.
The release of the photo essay by the National Archives is a good first step in response to the FOIA request, but it is only a small one. Without releasing the entire NCOI, however—including all the testimony and data upon which the court’s conclusions were based—sailors, historians, the surviving family members of the Thresher’s crew, and the American people cannot assess the accuracy or correctness of the court’s conclusions, or whether the pressures of great power competition on technological progress contributed to the loss of the ship and her crew.