Moskva (1959 icebreaker)

Russian icebreakers Admiral Makarov (left) and Moskva in 1992, shortly before the latter was sold for scrap. Both vessels were involved in two separate whale rescue operations in the 1980s.

In late December 1984, a Chukchi hunter spotted a herd of up to 3,000 beluga whales struggling for breathing room in small pools of open water in the ice-covered waters off the Chukchi Peninsula. Easterly winds had packed the narrow Senyavin Strait with drift ice up to 12 feet (4 m) thick, creating a wide ice pack that the whales could not cross on a single breath. While the locals tried to keep the animals alive by feeding them with frozen fish and keeping the breathing holes open, it soon became evident that the belugas would eventually perish unless they could be freed.[11][12]

In February 1985, Moskva was called from the Bering Sea in to break a channel through the ice pack and free the trapped herd. On 22 February, the icebreaker finally reached the belugas, but at first they refused to follow the ship to open water. However, when the crew began playing classical music through the ship's loudspeakers, the whales finally followed Moskva to the unfrozen sea.[11][12] In the end, it was estimated that about 2,000 whales escaped while slightly more than 500 were taken by the local hunters.[13] Using Moskva for the rescue operation, dubbed "Operation Beluga", cost the Soviet government about $80,000.[14][15]

In 1988, a similar rescue operation was attempted to free three gray whales from pack ice in the Beaufort Sea near Point Barrow, Alaska. As part of the $1 million effort, the United States Department of State requested help from the Soviet Union who sent two icebreakers, Admiral Makarov and Vladimir Arseniev, to break the ice trapping the whales.[16]

Moskva was 122.10 metres (401 ft) long overall and 112.40 metres (369 ft) at the waterline. At the widest point of the hull, the vessel had a beam of 24.50 metres (80 ft), but due to the sloping sides the maximum beam at waterline was slightly less, 23.50 metres (77 ft). At design waterline, the icebreaker drew 9.5 metres (31 ft) of water and had a displacement of 13,290 tonnes. However, the maximum draught of the vessel was 10.5 metres (34 ft), corresponding to a maximum displacement of 15,360 tonnes. Moskva was the largest non-nuclear icebreaker in the world at the time of the delivery,[3] having almost twice the displacement of the largest western icebreakers.

Designed to withstand the compression of the polar pack ice, the fully welded steel hull of Moskva was very strong. The 6-metre (20 ft) wide ice belt, where the hull plating was over 50 millimetres (2.0 in) thick in the bow, was designed to withstand ice pressures of up to 1,000 tonnes per square meter (about 1,400 psi), more than 30 to 60 times as much as normal merchant ships at the time. In bow and stern, the web frames were aligned perpendicularly to the shell plating. Longitudinally, the hull was divided into nine watertight compartments and the vessel had a full-length double hull below tweendeck.[3]

Moskva had single and double cabins for 109 persons. In addition to vessel crew and aviation detachment, accommodation and laboratories were reserved for scientists when the icebreaker carried out research expeditions in the polar waters. Special attention had been paid to the furnishing and decoration of the public spaces, which included a game room and a music room with a piano for the officers. The icebreaker was delivered from the shipyard with a total of three television sets.[3]

Designed to escort merchant ships through ice-covered waters, Moskva had a towing winch and a notch in the stern where the bow of the towed ship would be pulled. For ice reconnaissance, the icebreaker had a helicopter hangar and a landing platform in the stern. The vessel had two motor lifeboats for 60 persons and two 70-person lifeboats with manually operated propeller. In addition, the icebreaker carried a 11.5-metre (38 ft) motor launch with a steel hull, a 9-metre (30 ft) aluminum boat, two fiberglass ice sledge-boats, a 4.5-metre (15 ft) rowing boat and a light aluminum dinghy. The boats were launched using the icebreakers' two 10-ton deck cranes.[3]

Moskva was a diesel-electric icebreaker with a power plant consisting of eight 9-cylinder Wärtsilä-Sulzer 9MH51 single-acting two-stroke diesel engines, each of which was rated at 3,250 hp in continuous operation but capable of 10% overload for one hour at a time. The main engines were directly coupled to Siemens direct current (DC) generators that supplied electricity to propulsion motors through an applied Ward Leonard drive system. Normally, four generators were connected to the tandem electric motor driving the centerline propeller shaft and two generators to the propulsion motors driving the wing shafts, but the system allowed connecting two generators from the center circuit to either port or starboard circuit and vice versa in case of engine failure.[3]

The electric power produced by the main engines and generators was transformed into propeller thrust by three large DC motors coupled to the propeller shafts. The centerline propulsion motor, located in a separate compartment, was a tandem unit consisting of two 5,500 hp motors while the port and starboard propulsion motors, located side by side in the same compartment, were rated at 5,500 hp each. While the nominal speed of the propulsion motors was 115 rpm, full power was available at all revolution speeds between 110 and 150 rpm. The four-blade propellers were of fixed pitch type with the centerline propeller, which had twice the propulsion power of the wing shafts, having greater diameter than the port and starboard propellers. The icebreaker had a single centerline rudder.[3]

With an overall propulsion power of 22,000 hp, Moskva was at the time the most powerful diesel-electric icebreaker in the world. She was second only to the nuclear-powered Lenin which, at 44,000 hp, had twice the power of the Moskva-class icebreakers.[3] While the most powerful western icebreaker at the time, the 1955-built USS Glacier, had two propulsion motors rated at 10,500 hp each and was thus nearly as powerful as Moskva, the American icebreaker could only maintain the peak 21,000 hp in four-hour increments and was rated for 16,900 hp in continuous operation.[17]