Russia Brings World’s Most Heavily Armed Combat Ship Back to Arctic Port After Sea Trials

The Russian Navy’s extensively modernised nuclear-powered battlecruiser Admiral Nakhimov has returned to port Severodvinsk following another phase of sea trials, marking continued progress towards the vessel’s long-awaited return to operational service. The warship, which is by far the largest and most heavily armed surface combatant in the world, has spent over a decade undergoing a comprehensive modernisation intended to transform it into what is now by far the most capable combat ship in the Russian fleet. The trials are understood to have included assessments of onboard systems following the installation of extensive new weapons, sensors, propulsion upgrades, and combat management equipment. The return to port will allow engineers and naval specialists to analyse the results before the ship proceeds to subsequent testing phases.

Requirements for the Admiral Nakhimov’s sea trials are far more extensive than the norm for refurbished vessels, and reflect the immense scale of the reconstruction, which has been so extensive that many Russian analysts have described the vessel as being effectively rebuilt rather than merely refurbished. Large sections of onboard equipment were removed and replaced, while power generation, communications systems, sensors, command facilities, and internal infrastructure were comprehensively modernised. The program has consequently experienced numerous delays over more than a decade, reflecting both its technical complexity and the financial challenges associated with restoring such a large warship.

The Admiral Nakhimov was on June 26 confirmed to have returned to its home port of Severomorsk after 29 years out of service for refurbishment work, with the vessel reported to be near the end of its sea trials. The Nakhimov was re-floated on July 25, 2025, before setting sail under its own power for the first time in 28 years in August 2025, and beginning the final phase of its sea trials on June 1. Severomorsk is the headquarters and principal surface fleet base of the Navy’s Northern Fleet, located on the eastern shore of Kola Bay, and is prized for its year-round ice-free access to the sea. Alongside the Admiral Nakhimov, it also hosts the bulk of the country’s nuclear powered submarine fleet, with the newly refurbished cruiser expected to be tasked with protecting the Navy’s submarine-based nuclear arsenal. 

The Admiral Nakhimov’s displacement of 28,000 tons is larger than many aircraft carriers and approximately triple the size of a large destroyer. Its air wing is by far the largest of any combat ship in the world, allowing it to embark three modernised Ka-27M anti-submarine warfare helicopters, which are considered particularly valuable for Arctic operations. A further particularly unique feature is the ship’s status as the only surface combat ship in the world with a nuclear propulsion system, which facilitates a virtually unlimited range, and provides exceptional endurance at high speed. While conventional gas turbine or diesel-powered warships consume fuel rapidly when operating at maximum speed, forcing commanders to balance speed against endurance, Kirov class cruisers can sustain speeds above 30 knots for very extended periods.