Commended for his performance, Motsak graduated to various staff positions in the fleet, was promoted to rear-admiral in 1993 and became commander 1st Submarine Flotilla [ru] in 1993.

Motsak was deeply involved in rescue attempts to reach the stricken submarine before officials learned that the entire crew of 118 had died.

[2] He graduated in 1972 with a specialty in submarine missile guidance systems, and was assigned to serve as a senior engineer in the Pacific Fleet.

[1][3][4] On 15 June 1994 he was awarded the title of Hero of the Russian Federation, with the accompanying Gold Star "for courage and heroism shown in the performance of military duty".

[2][3] In August 1995 he oversaw a missile-firing exercise from a Typhoon-class submarine at the North Pole, commanded by Aleksandr Bogachyov [ru].

[5] Several submarines were assigned to the exercises: the Borisoglebsk, Karelia, Leopard, Obninsk  [ru], Daniil Moskovsky, and the Oscar II-class Kursk.

On 11 August the crew of the Kursk, led by Captain 1st Rank Gennady Lyachin, carried out a test launch of a Granit cruise missile.

[8] Some hours after the explosion, concerned at the Kursk's failure to report in, Popov ordered Motsak to alert the fleet's rescue forces.

Six hours after the Kursk's sinking, Motsak ordered the fleet's rescue vessel, the Mikhail Rudnitsky to come to one-hour readiness to put to sea.

[9] An hour later Motsak ordered five Ilyushin Il-38s to begin searching the exercise area, subsequently supplementing the effort with six helicopters.

[14] During the recovery of bodies, a note written by Dmitry Kolesnikov, the senior ranking survivor of the initial explosions, was found.

[15] Motsak oversaw the salvage operation to raise the wreck of the Kursk between July and October 2001, with the Udaloy-class destroyer Severomorsk as his flagship.

[18] Reflecting on the hazardous nature of the operation, he said to the assembled experts that "once we reach the shore, we will have a good drink, according to Russian custom.

[20] A subsequent investigation led by Prosecutor General Vladimir Ustinov laid part of the blame for the tragedy on Motsak, and Captain 1st Rank Teslenko, chief of the Northern Fleet's submarine rescue service.

[2] On 1 December 2001 Motsak was demoted, along with Admiral Popov and Vice-Admiral Oleg Burtsev, the commander of the 1st Submarine Flotilla, while eleven other senior naval officers were sacked.

[2] In 2009 both Motsak and Klebanov were implicated in a political scandal related to the use of the historic cruiser Aurora as a venue for parties for VIPs.

He became head of Marine Integrated Systems LLC, and from 2015 was CEO of a private company involved in the construction of ships, boats and floating structures.

[24] Retired admiral Vladimir Valuev [ru] stated that Motsak was a "real submariner, a competent specialist and a caring commander.