It was during exercises in August 2000, led by the admiral aboard the "Pyotr Velikiy", that the submarine K-141 "Kursk" suffered a fatal accident and sank. Kasatonov's ship was the first to locate the stricken submarine sixteen hours after her sinking and became the command ship for the recovery efforts. He continued in command of "Pyotr Velikiy" until 2005, having been promoted to rear-admiral during this period. He then took up staff positions with the Northern Fleet's missile ship division and carried out several long distance voyages with divisions of ships. He became chief of staff and first deputy commander of the Pacific Fleet in 2012, and in 2016 took up the position of head of the Naval Academy. This was followed by his posting in 2019 to be deputy commander in chief of the navy. He has received numerous medals over his career, as well as the Orders of Military Merit and Naval Merit. His life, as well as those of his relatives, is commemorated in a museum in Belenikhino, Belgorod Oblast.