Трагедия атомной подводной лодки «Трешер» (SSN-593)

United States Navy submarine (1961–63)

USS Thresher (SSN 593) was the lead boat of her class of nuclear powered attack submarines in the United States Navy. She was the U. S. Navy's second submarine to be named after the thresher shark. On 10 April 1963, Thresher sank during deep diving tests about 220 mile (354 km) east of Cape Cod, Massachusetts, killing all 129 crew and shipyard personnel aboard. Her loss was a watershed for the U. S. Navy, leading to the implementation of a rigorous submarine safety program known as SUBSAFE. The first nuclear submarine lost at sea, Thresher was also the third of four submarines lost with more than 100 people aboard, the others being the French Surcouf, sinking with 130 personnel in 1942, USS Argonaut, lost with 102 aboard in 1943, and Russian Kursk, which sank with 118 aboard in 2000. Following Navy tradition, this class of subs was originally named Thresher after the lead boat. When Thresher was struck from the Naval Vessel Register on 16 April 1963, the class name was changed to that of the second boat, Permit. Having been lost at sea, Thresher was not decommissioned by the U. S. Navy and remains on "Eternal Patrol".

The contract to build Thresher was awarded to Portsmouth Naval Shipyard on 15 January 1958, and her keel was laid on 28 May 1958. She was launched bow first on 9 July 1960, was sponsored by Mary B. Warder (wife of World War II skipper Frederick B. Warder), and was commissioned on 3 August 1961, Commander Dean L. Axene commanding. Thresher conducted lengthy sea trials in the western Atlantic and Caribbean Sea areas in 1961–1962. These tests allowed a thorough evaluation of her many new and complex technological features and weapons. She took part in Nuclear Submarine Exercise (NUSUBEX) 3–61 off the northeastern coast of the United States from 18–24 September 1961. Thresher conducted further trials and fired test torpedoes before returning to Portsmouth on 29 November 1961. The boat remained in port through the end of the year, and spent the first two months of 1962 with her sonar and SUBROC systems under evaluation. In March, she participated in NUSUBEX 2–62 (an exercise designed to improve the tactical capabilities of nuclear submarines) and in anti submarine warfare training with Task Group ALPHA.

On 9 April 1963, Thresher, commanded by Lieutenant Commander John Wesley Harvey, left from Kittery, Maine, at 8:00 a. m. and met with the submarine rescue ship Skylark at 11:00 a. m. to begin her initial post overhaul dive trials, in an area some east of Cape Cod, Massachusetts. That afternoon, Thresher conducted an initial trim dive test, surfaced, and then performed a second dive to half of her 1,300 foot (400 meter) test depth. Before she entered the yard in late 1962, the Thresher had been to her test depth about 40 times. She remained submerged overnight and re established underwater communications with Skylark at 6:30 a. m. on 10 April to commence deep dive trials. Following standard practice, Thresher slowly dove deeper as she traveled in circles under Skylark – to remain within communications distance – pausing every 100 feet (30 m) of depth to check the integrity of all systems. As Thresher neared her test depth, Skylark received garbled communications over underwater telephone indicating "  minor difficulties, have positive up angle, attempting to blow", and then a final, even more garbled message that included the number "900". When Skylark received no further communication, surface observers gradually realized a problem had occurred. By mid afternoon, 15 Navy ships were en route to the search area. At 6:30 p. m., the commander of Submarine Force Atlantic sent word to Portsmouth Naval Shipyard to begin notifying the crew's family members, starting with Commander Harvey's wife Irene, that Thresher was missing. Chief of Naval Operations Admiral George W. Anderson Jr. went before the press corps at the Pentagon to announce that the submarine was lost with all hands. President John F. Kennedy ordered all flags to be flown at half staff from 12 to 15 April in honor of the 129 lost submariners and shipyard personnel.

The Navy quickly mounted an extensive search with surface ships and support from the Naval Research Laboratory (NRL), with its deep search capability. The laboratory's small acoustic research vessel Rockville, with a unique trainable search sonar, left on 12 April 1963 for the search area. Rockville was to be followed by other personnel with a deep camera system. USS Allegheny, USNS Mission Capistrano, and USS Prevail became engaged in a close sonar search of an area square. RV Atlantis II, USNS Robert D. Conrad, and USNS James M. Gilliss investigated likely contacts found in the sonar search. The NRL deep towed camera system and personnel later operated from James M. Gilliss with some success, finding debris later confirmed to be from Thresher. The bathyscaphe Trieste was alerted on 11 April and brought from San Diego to Boston. It was deployed for two series of dives into the debris field; the first taking place from 24 to 30 June, and the second from late August until early September. The equipment handling capability of Gilliss proved inadequate, even hazardous, to handle the towed vehicle, and the entire search was paused in September. By morning on 11 April, submarines USS Seawolf and USS Sea Owl, both operating near Thresher’s location, were ordered to join in the search for the missing submarine as well. The inadequacy of the existing small Auxiliary General Oceanographic Research (AGOR) vessels such as James M. Gilliss for handling deep towed search vehicles led to a search for a vessel of a size and configuration that could handle such equipment in a sheltered area. In late 1963, that search resulted in the acquisition of , with the intent to eventually add a sheltered center well for deploying equipment. Mizar sailed on 25 June to begin the deep search and found the wreck within two days. The shattered remains of Threshers hull were on the sea floor, about 8400 feet (2560 m) below the surface, in five major sections. Most of the debris had spread over an area of about Major sections of Thresher, including the sail, sonar dome, bow section, engineering spaces section, operations spaces section, and the stern planes were found. By July 22, most of the lost submarine had been photographed. In early August, the entire task force returned to the area with the submersible. Its first two dives were unsuccessful, but on the third dive, the UTE enabled placement of Trieste II on the wreck, at first not seeing wreckage because the bathyscaphe was sitting upon it. Ultimately, the Court of Inquiry determined

That while operating as a unit of the search force, the U. S. S. Seawolf (SSN575) recorded possible electronic emissions and underwater noises. None of the signals which SEAWOLF received equated with anything that could have been originated by human beings.

Deep sea photography, recovered artifacts, and an evaluation of Thresher's design and operational history permitted a court of inquiry to conclude that the submarine had probably suffered the failure of a salt water piping system joint that relied heavily on silver brazing instead of welding. Earlier tests using ultrasound equipment found potential problems with about 14% of the tested brazed joints, most of which were determined not to pose a risk significant enough to require repair. But on 30 November 1960, nearly three years prior to the accident, Barbel suffered such a silver braze joint failure near test depth while on an exercise, flooding the engine room with an estimated 18 tons of water in the 3 minutes it took to surface under power and with blown tanks. This incident was followed months later by more silver braze failures aboard the ballistic missile submarine Abraham Lincoln during trials. Air dryers were later retrofitted to the high pressure air compressors, beginning with Tinosa, to permit the emergency blow system to operate properly. Submarines typically rely on speed and deck angle (angle of attack) rather than deballasting to surface; they are propelled at an angle toward the surface. Ballast tanks were almost never blown at depth, as doing so could cause the submarine to rocket to the surface out of control. Normal procedure was to drive the submarine to periscope depth, raise the periscope to verify that the area was clear, and then blow the tanks and surface the submarine. At the time, reactor plant operating procedures did not allow for a rapid reactor restart following a scram, or even the ability to use steam remaining in the secondary system to propel the submarine to the surface. After a scram, standard procedure was to isolate the main steam system, cutting off the flow of steam to the turbines providing propulsion and electricity. This was done to prevent an overly rapid cool down of the reactor. Threshers reactor control officer, Lieutenant Raymond McCoole — a "mustang" with years of submarine service in enlisted status, serving as a chief petty officer aboard the first nuclear submarine, USS Nautilus (SSN 571) before becoming a commissioned officer — was not on the boat during the fatal dive; his trainee, Jim Henry, fresh from nuclear power school, probably followed standard operating procedures and gave the order to isolate the steam system after the scram, even though Thresher was at or slightly below its maximum depth. Once closed, the large steam system isolation valves could not be reopened quickly. Reflecting on the situation in later life, McCoole was sure that he would have delayed shutting the valves, thus allowing the boat to "answer bells" and drive itself to the surface, despite the flooding in the engineering spaces. Admiral Rickover noted that the procedures were for normal operating conditions, and not intended to restrict necessary actions in an emergency involving the safety of the ship. After the accident Rickover further reduced plant restart times, which had already been gradually improving with new technology and operating experience, in addition to limiting factors that could cause a shut down. The U. S. Navy has periodically monitored the environmental conditions of the site since the sinking and has reported the results in an annual public report on environmental monitoring for U. S. naval nuclear powered craft. These reports provide results of the environmental sampling of sediment, water, and marine life, which is performed to ascertain whether Threshers nuclear reactor has had a significant effect on the deep ocean environment. The reports also explain the methodology for conducting deep sea monitoring from both surface vessels and submersibles. The monitoring data confirm that there has been no significant effect on the environment. Nuclear fuel in the submarine remains intact. Information declassified in the 2008 National Geographic Documentary Titanic: Ballard's Secret Mission shows that USNR Commander Robert Ballard, the oceanographer credited with locating the wreck of , was sent by the Navy on a mission under cover of the search for Titanic to map and collect visual data on the wrecks of both Thresher and Scorpion. Ballard had approached the Navy in 1982 for funding to find Titanic with his new deep diving robot submersible. The Navy conditionally granted him the funds if the submarine wrecks were surveyed before Titanic. Ballard's robotic survey showed that the depth at which Thresher had sunk caused implosion and total destruction; the only recoverable piece was a foot of mangled pipe. His 1985 search for Scorpion revealed a large debris field "as though it had been put through a shredding machine". His obligation to inspect the wrecks completed, and with the radioactive threat from both established as small, Ballard then searched for Titanic. Financial limitations allowed him 12 days to search, and the debris field search technique he had used for the two submarines was applied to locate Titanic. Almost all records of the court of inquiry remain unavailable to the public. In 1998, the Navy began declassifying them, but decided in 2012 that it would not release them to the public. In February 2020, in response to a FOIA lawsuit by military historian James Bryant, a federal court ordered the Navy to begin releasing documents by May 2020. On May 22, 2020, the Navy stated in a court mandated status report that due to the ongoing COVID 19 pandemic, the Navy's Undersea Warfare Division (OPNAV N97) had placed the records review on hold as N97 staff were limited to supporting mission essential tasks supporting undersea forces and operations only. However, the Navy stated that they "will return to the review and process of Plaintiff’s FOIA request once the office is able to expand beyond mission essential capabilities". Following the release of the July 18, 2020, court mandated report, the Navy stated that they had identified and approved additional resources and reservists to begin processing the documents in August. The Navy began a rolling release of the records on September 23, 2020. The aftermath of the public relations aspect of this major disaster has since been part of various case studies.

On 8 April 2013, Bruce Rule, US Office of Naval Intelligence lead acoustic analyst for over 42 years, published his own analysis of the data collected by USS Skylark and Atlantic SOSUS arrays in a paper in the Navy Times. Rule based his analysis on SOSUS data that was highly classified in 1963, was not discussed in open session of the Court of Inquiry and was not revealed at the congressional hearings. Rule concluded that the primary cause of the sinking was a failure of the electrical bus that powered the main coolant pumps. According to Rule, SOSUS data indicates that after two minutes of electrical instability, the bus failed at 09:11 a. m., causing the main coolant pumps to trip off. This caused an immediate reactor scram, resulting in a loss of propulsion. Thresher could not be deballasted because ice had formed in the high pressure air pipes, and so she sank. Rule's analysis holds that flooding (whether from a silver brazed joint or anywhere else) played no role in the reactor scram or the sinking, and that Thresher was intact until she imploded. In addition to the SOSUS data that does not record any sound of flooding, the crew of Skylark did not report hearing any noise that sounded like flooding, and Skylark was able to communicate with Thresher, despite the fact that, at test depth, even a small leak would have produced a deafening roar. Additionally, the previous commander of Thresher testified that he would not have described flooding, even from a small diameter pipe, as a "minor problem".

On 12 April 1963, President John F. Kennedy issued paying tribute to the crew of Thresher by ordering all national flags to half staff. Five folk music groups or artists have produced songs memorializing Thresher; "Ballad Of The Thresher" by The Kingston Trio, "The Thresher Disaster" by Tom Paxton; "The Thresher" by Phil Ochs on his 1964 album All the News That's Fit to Sing, "The Thresher" by Pete Seeger, and "Thresher" by Shovels & Rope. "The Fear Makers", an episode in the 1964 season of the television series Voyage to the Bottom of the Sea, is inspired by the loss of the USS Thresher. Anthony Wilson, a writer for the series, was fascinated by the loss of the USS Thresher (and with 'fear gas' as an incapacitating chemical weapon aboard the submarines, an agent similar to the contemporary BZ gas), and he wrote a teleplay for the series. In Wilson's teleplay, the submarine, Seaview, searches for a missing submarine, Polidor.