During the last ten years the MIR-1 and MIR-2 submersibles have been used not only for scientific research of the ocean, but also for the location and exploration of wrecks on the ocean floor
In 1989 the Russian nuclear submarine Komsomolets sank in the Norwegian Sea in 1,700 m water depth The R/V Akademik Mistilav Keldysh, with the MIR submersibles on board, has conducted seven expeditions to the Komsomolets wreck Scientific research of the environment around the wreck and radiation monitoring were performed during these expeditions The unique operation of encapsulating the bow part of the wreck was carried out by the MIR submersibles
In November 1998 the MIR submersibles explored and filmed the Japanese submarine wreck 1–52, which lies in the Mid-Atlantic in 5,400 m water depth 14 submersible dives were carried out in a period of 13 days
Various aspects of deep ocean operations on these two submarine wrecks will be discussed
In 1989 scientific research and underwater operations began on the wreck of the nuclear submarine Komsomolets in the Norwegian Sea Representatives of more than twenty Russian organizations, Norway, Holland, the United Kingdom, Switzerland, and the United States took part in expeditions to investigate the Komsomolets wreck from 1990 to 1995
As a result of a fire onboard, the Komsomolets sank on 7 April 1989 In a depth of 1,700 m in the Norwegian Sea, 180 nautical miles to the south of Bear Island 42 men died and there were 19 survivors
Following this accident, the R/V Akademik Mistilav Keldysh, with the two deep manned submersible Ms IR-1 and MIR-2 on board, made the first expedition to the wreck site in the middle of May 1989 The main purpose of the expedition was observation of the wreck and finding out the cause of the accident It was established that the submarine was intact on the bottom, sunk into the sediments to 2 5 m Some distortions of the fairing and of the pressure hull in the bow part of the wreck were observed Radiation measurements around the wreck revealed that the radiation is at a background level, which is much lower than in some large industrial cities
Beginning in 1991, the P P Shirshov Institute of Oceanology has conducted annual expeditions to the area of the Komsomolets wreck The man objectives of these expeditions were research into the environmental situation at the wreck and In the immediate vicinity, study in detail of the distortions of the submarine body, and monitoring of the conditions inside the bow of the submarine, where two torpedoes with nuclear warheads are located
During six expeditions to the site underwater radiation monitoring was continuously conducted Several types of radiation monitoring equipment were installed on the MIR submersibles The instruments were designed and manufactured at various scientific and engineering organizations in Russia Several types of gamma-spectrometer, sampling devices for the collection of the sediments, water and suspensed matter, and special sorbents for the absorption of radionuclides from the water
