Submarine incident off Kildin Island

The Submarine Incident off Kildin Island was a collision between the US Navy nuclear submarine USS Baton Rouge (SSN-689) and the Russian Navy nuclear submarine B-276 Kostroma near the Russian naval base of Severomorsk, on 11 February 1992. The incident took place when the US unit was engaged in a covert mission, apparently aimed at intercepting Russian military communications. Although a majority of sources claim that the American submarine was trailing her Russian counterpart, some authors believe that neither the Kostroma nor the Baton Rouge were able to locate each other before the collision.

Background
Right after the 1991 fall of the Soviet Union, uncertainty prevailed among the US intelligence community about the attitude of the former Soviet forces, especially those strategic assets that remained under Russian control. The US government tasked the US Navy to continue to keep a close watch on the main bases of Russian nuclear submarines to monitor developments. During the cold war, this kind of submarine surveillance was known as "Operation Holy Stone"; submariners nicknamed the program "Operation Pinnacle" or "Bollard". Author Jeffrey T. Richelson maintains that "Holy Stone" continued unabated, and that the 1992 incident was part of the operation. This intelligence gathering included the tapping of Soviet submarine communication cables, the recording of the pattern of noises from Soviet submarines, and the observation of submarine-launched ballistic missile tests.

Blind encounter
The ramming occurred at 8:16 pm local time, at a point slightly over 12 miles from the shoreline, in waters the United States regarded as international, and by Russia as five miles inside the Russian territorial sea (due to the Russian use of a straight baseline.) The mission of Baton Rouge off Severomorsk was reportedly the recovery or delivery of intelligence-monitoring devices on the seabed. The American press claimed that the submarine was checking wireless traffic between Russian bases, but the Russian counterpart asserted that the two boats were engaged in a ‘cat-and-mouse game’, an opinion supported also by a number of Western sources. According to naval analyst Eugene Miasnikov, the amount of antisubmarine surveillance deployed by the Russians along their shores makes the first possibility implausible. The second argument also seems to be weak, he asserts, given the circumstances, and the collision itself seems to have happened by chance. The breaking waves and the shallow waters of that area of the Barents sea prevented early detection of the other by either submarine, which at the time of the incident were using only their passive sonars, by creating too much ‘noise’ around. Miasnikov maintains that the submarines of the Los Angeles class are unable to detect acoustic signals from targets located within a cone of 60 degree astern, thus the most probable scenario was that Kostroma approached Baton Rouge from behind. Indeed, the collision took place when the Kostroma was surfacing, hitting the US submarine underneath on her aft section. The Sierra class sonar is also ‘deaf’ to the aft direction; her usual pattern of acoustic search is moving along a loop course. The incident, however, implied that Russian attack submarines are capable of avoiding passive acoustic detection, at least under certain conditions.

Damage


Both submarines sustained damage, but there were no casualties reported. Russian reports and American aerial surveillance agree that the Kostroma's sail was dented on its front section. Russian navy sources reportedly found pieces of composite material from Baton Rouge's anti-sonar tiles. The US Navy claimed that besides some scratches, dents, and two minor cuts on her port ballast tank, the Baton Rouge didn’t suffer major damage, but it was necessarily serious in any case, as any rupture on the single hull of Baton Rouge would have compromised her pressure resistance. The deactivation of Baton Rouge was announced on 17 September 1993, although some sources claim that the American submarine had been already taken out of service less than a year after the incident, in January 1993. According to Gregory Stitz, curator of Arkansas Inland Maritime Museum, and some European sources the costs of repairing the damaged pressure hull, along with a programmed refueling, were well beyond the planned budget; therefore the US Navy chose to decommission the submarine. Russian naval officers alleged that the US submarine became a constructive total loss right after the collision. As for Kostroma, it was laid up on 28 March 1992, and by 29 June had been fully repaired at Nerpa shipyards in Snezhnogorsk. The Russian submarine was temporarily renamed Krab, before recovering her original name on November 1996. After a huge overhaul, again at Nerpa, she returned to service in 2005.

Political consequences


The incident produced intense embarrassment in Washington. Russian complained via diplomatic channels, and the Pentagon quickly acknowledged that a collision had happened, contrary to the official policy until then. A meeting between Secretary of State James Baker and Russian president Boris Yeltsin was arranged immediately. The Russian navy accused the United States of continuing intelligence operations around Russia's home waters, despite the end of the cold war. All this prompted the US Navy to stop some specific submarine activities off Russian bases, such as tapping underwater cables or intercepting wireless communications. This measure, however, did not prevent a later incident in March 1993, when the Sturgeon-class submarine USS Grayling (SSN-646) collided with a Delta class submarine, K-407 Novomoskovsk off Kola peninsula.