Sweden Releases Classified Documents on the 1981 Incident Involving the Soviet Submarine S-363

Sweden has declassified documents related to the 1981 incident involving the Soviet submarine S-363, which ran aground off the country’s coast while carrying nuclear torpedoes.

Michael Fredholm, a former employee of the Swedish National Defence Radio Establishment, shared his findings from these documents with SVT.

Theories about what exactly happened when the Soviet submarine with hull number 137 ran aground near Karlskrona in the fall of 1981 varied.

“A picture has emerged that differs from the interpretation of the event at the time,” Fredholm says.

According to his findings, it was Sweden’s actions that created a conflict that did not actually exist, thereby increasing the risks for the country rather than reducing them.

His assessment differs from the interpretation of the incident at the time as a deliberate incursion.

That year, Prime Minister Turbjörn Fälldin, known for his hardline stance on violations of Swedish neutrality, led the government.

First and foremost, it is clear that the government made a tough decision within ten minutes. At that moment, there was no other information available besides the fact that a Soviet submarine had run aground.

When the submarine ran aground near the Karlskrona naval base, Sweden immediately:

• surrounded the area with military forces;
• interrogated the crew;
• accused the USSR of violating territorial waters;
• and, following a diplomatic crisis, allowed the submarine to leave Swedish waters.

Instead, the version that the submarine had navigation problems is confirmed.

“This is a compelling argument for why it is important to have historical awareness when we assess current events, to avoid repeating the mistakes made in the past,” Fredholm noted.

Timeline of the incident

On September 16, 1981, the diesel submarine S-363 (hull No. 137, Project 613) of the 157th Submarine Brigade of the Soviet Baltic Fleet departed from Paldiski on a training mission. Captain 3rd Rank Anatoly Gushchin was the commander.

During the voyage, S-363 carried two torpedoes with nuclear warheads.

On October 18 at 6:10 p.m., while submerged, the submarine collided with the trawl of a fishing seiner. The radio direction finder antenna was damaged, and malfunctions occurred in the sonar and the Decca system. The commander did not report the incident to shore and did not take additional navigational measures.

Due to gross errors in determining the position (the navigator, Senior Lieutenant Anatoly Korostov, was insufficiently qualified, did not use a sextant, and operated the Decca system incorrectly), the error in the observation grew to tens of miles. The submarine lost its bearings.

On October 27 at 21:57, S-363, traveling at a speed of 7.5 knots, struck the rocks of a coastal shoal near Turumsher Island in the vicinity of the Karlskrona naval base, Sweden. The boat ran aground with a list of up to 15° to port.

On October 28, Swedish fisherman Bertil Styrkman discovered the boat. The information was relayed to the authorities.

The submarine remained aground for 10 days under the guard of Swedish forces. On November 6, 1981, a Swedish tugboat refloated S-363 and towed it to the territorial waters boundary. The submarine then proceeded on its own toward Soviet ships.

Following the investigation, the boat’s commander, Captain 3rd Rank Anatoly Gushchin, was relieved of his command. Captain 1st Rank Avrukevich, the commander of the 157th Brigade, was dismissed from the Armed Forces.