Specialists of the PM-12 mother ship of the Northern Fleet started unloading the stern reactor of the Kursk nuclear submarine on Monday. The cover of the second reactor was removed successfully. Rostislav Rimdenok, chief engineer of the Nerpa dock, said that the operation will probably be finished by February 20. He noted that the operation on the stern reactor will have some peculiarities. The chief engineer also noted that designers of nuclear reactors are examining the reactor in order to find how it reacted to the explosions, as a result of which the Kursk submarine sunk.