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The K-152 sub’s accident was an incident that occurred aboard the new Russian nuclear attack submarine NERP A, which was built for the Indian Navy, on November 8, 2008. It resulted in the death of 20 people and injuries to 41 more. Three of the dead were military personnel and the rest were civilians from the Vostok, Zvezda, Era and Amur shipbuilding yards, who were members of the acceptance team. The deaths and injuries were caused by unsanctioned release of fire suppressant gas during a submerged test run in process of the sub’s sea trials in the Sea of Japan. The sub itself was not damaged by the incident, which was the worst Russian submarine disaster since KURSK sank in 2000.

At the time of the accident NERP A was undergoing sea trials at the Russian Pacific Fleet’s test range in Peter the Great Gulf, an inlet of the Sea of Japan adjoining the coast of Russia’s Primorsky Krai Province. The submarine had not yet been accepted by the Russian Navy but was undergoing complex tests under the supervision of a team from the Amursky and other shipbuilding plants. For this reason it had a much larger complement aboard, totaling 208 people, 81 military personnel and 127 civilian specialists from the production enterprises.

The accident occurred at 8:30 p.m. local time, during the submarine’s first underwater test run. The submarine fire extinguishing system was triggered, sealing two forward compartments and filling them with freon gas (dibromo- tetra fluoroethane, known as khladon in Russian). The gas, a hydro bromo fluorocarbon refrigerant, is used in the Russian Navy’s LOKh (lodochnaya obyemnaya khimit sceskaya – “submarine volumetric chemical”) fire suppressant system. Each compartment of such a Russian submarine contains a LOKh station, from which freon can be delivered into that or adjacent compartment. Freon displaces oxygen, enabling it to extinguish fires rapidly in enclosed spaces. In high concentrations it is narcotic, which progresses by stages into excitation, mental confusion, lethargy and ultimately asphyxiation.

The Governor of Russia’s Chabarovsk Region, Viktor Ishaev, rejected the human factor as a possible reason for the breakdown on board the nuclear submarine. The introductory investigation shows that there were no wrong actions taken by the crew. “The so called human factor has not been discovered,” Inter fax quoted the governor as saying.

An official version of the tragedy says that it happened be- cause of inadvertent occurrence of function of the fire- extinguishing system, which released freon gas into two front compartments of the submarine. Twenty people – three servicemen and 17 civilian individuals – died as a result of gas poisoning.

Experts, however, believe that the accident occurred because of the human factor and not the technical malfunction. Everything on board the sub, that can be tested, is tested at the factory, at first at the pier, above the water surface. Afterwards, they say, submarines are tested for their performance under the water.

“There were many outsiders on board to conduct all the tests. As a rule, these people do not know how to behave on board the submarine. They only know how to fix a device, which they made at their enterprises. Almost none of them has ever been on a submarine before, but they want to be there, because of financial reasons”, said an expert.

“Contractors drink a lot during tests, they do it all the time. Someone could simply light up a cigarette in a compartment, which activated the fire extinguishing system. Someone else was probably sleeping in the compartment and was unable to understand what was going on there,” the expert added.

The NERP A submarine was outfitted with an up to date automatic fire extinguishing system on the insistence of the Indian customers. All the instructions for the system were written in English.

Freon is used, if fire breaks out on board, but the source of it remains unknown. Only the Commanding Officer has the right to order freon release. However, experts say, that the system on NERPA was activated automatically.

All is OK, but there is a question: Where at the time of the accident was the Sub’s Commanding and Engineering Officers, what were they doing and what are their names? Why is it a secret and why were their names not mentioned in any of the publications?

It is relevant to provide for a reader the tactical-technological characteristics of the Russian attack nuclear submarines NERP A (Project 971) type (Editor’s Note: NATO designation: AKULA), which was first designed in 1980s under the direction of Saint- Petersburg Number 143 Design Bureau Chief Designer Georgy Thatcherism and Chief Navy Supervisor Captain First Rank Igor Bogatchenko (the first SSN of that project was built on the Komsomolsk-on-Amur Shipyard and delivered to the Pacific Fleet in 1984) In the Russian Navy there are now 10 submarines of that project.

In conclusion, it is reasonable to propose some changes in the practice of Russian new nuclear submarines post construction sea trials.

First, the conclusive sea trials of nuclear submarines must be accomplished by a team of professionals like in aviation is done by test pilots. After finishing those tests they will transfer a submarine to a regular crew. The test submariners must teach a regular crew to control a new tested sub. Of course, such practice will be most expensive but advantages in safety and quality of testing and crew education would be much more important.

A new nuclear submarine is not a Noev Covtcheg for new- comers but an extremely dangerous and expensive weapon system, and testing of such extremely dangerous machine must be trusted to only very highly qualified test submariners.

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