K-429 (often incorrectly referred to as K-329) was a Project 670-A Скат (Skat, meaning "ray"; also known by its NATO reporting name of Charlie I-class) nuclear submarine of the Soviet Navy. Her keel was laid down on 26 January 1971 at Krasnoye Sormovo in Gorky. She was launched on 22 April 1972, and was commissioned on 31 October 1972 into the Soviet Pacific Fleet. Sinking incidents In early 1983, K-429 returned to base needing overhaul after a long patrol. After turning their boat over to the shipyard, crew departed on leave. Her nuclear weapons remained aboard. Ordered to sea That June, Captain First Rank Nikolay Suvorov was ordered by Rear Admiral Oleg Yerofeyev to reassume command of K-429 and to take part in an exercise. Suvorov questioned the order: the exercises had been planned for later in the year, the boat was being repaired, the crew was on leave, and Suvorov expected a transfer to Saint Petersburg. Yerofeyev explained that Suvorov's Communist Party membership would be revoked and he would have to face a tribunal if he asked such questions. Without Communist Party membership, Suvorov would not be allowed to command a warship. Suvorov recalled his crew and returned to K-429. Much of the crew could not be contacted, and their places were filled by sailors from the naval base and from five other boats that were in port at the time. Nearly one-third of the 120 crewmen had never been on K-429 before, and none of them received any training on K-429. On 23 June 1983, K-429 was ordered to proceed immediately to the torpedo firing range. Suvorov refused that order, replying that standard operating procedures required him to perform a test dive first. The sinking In the late evening on 23 June, K-429 arrived at her testing area in Sarannaya Bay, just south of Petropavlovsk-Kamchatsky, and Suvorov gave the order to dive to periscope depth. However, he had not given the preliminary command to set the diving watch — the crew neither aligned the boat's systems for sea, nor were they at their stations to control the boat during the dive. Because the boat had not been prepared to dive, instrumentation valves were not aligned properly, and even though the main ballast tanks were filling, their indicators read empty. Confused, Suvorov ordered auxiliary ballast tanks filled. Over-ballasted to about 60 tons negative buoyancy, the boat dived very quickly.