The revolutionary icebreaking rescue vessel Baltika, developed by Aker Arctic and propelled by Steerprop, is the first vessel ever built with an asymmetric hull design that allows it to break ice ahead, astern and sideways. Because of this capability, this relatively small icebreaker is able to open a much wider channel in ice than other icebreakers of similar size. Steerprop was a natural choice for delivering a propulsion system to match the tough requirements set by both the Baltika’s versatile operations and the harsh, arctic environment.
The Baltika is a true multipurpose vessel, designed for icebreaking operations in harbors and adjacent waters. Because of the asymmetric hull design this relatively small icebreaker can break ice ahead, astern and sideways and is able to open a wide enough channel in ice even for large merchant ships. In addition, the vessel can be used for towing of vessels and floating facilities in an emergency, extinguishing external fires and performing various rescue operations. The vessel is also fitted with a sophisticated built-in oil recovery system. In case of oil spill, the vertical side of the asymmetric hull moves oil floating on the surface to a built-in skimmer as the vessel moves obliquely (sideways) through the oil.
Baltika was built by Arctech Helsinki Shipyard in co-operation with Shipyard Yantar JSC based on Aker Arctic’s oblique icebreaker design, Aker ARC 100.
Because of the sophisticated multipurpose operations of this vessel, the demands on the propulsion system were high. The azimuth thrusters would need to match the critical requirements for outstanding performance and maneuverability - not only would they need to push the vessel nearly sideways both in rough seas and through thick ice, but they would also need to make the vessel turn around almost on the spot. This was a challenge Steerprop was more than confident to take on, and today the Baltika is propelled by three SP 60 PULL 2.5 MW Steerprop Azimuth Propulsors, two in the stern and one in the bow of the vessel, a solution that was successfully tested and verified in 2015.
In March 2015, Baltika departed from Murmansk and sailed to the Kara Sea to carry out full-scale ice trials, where the vessel’s icebreaking performance was verified and its full operational capabilities were demonstrated. The testing program included performance tests in two distinct ice thicknesses in ahead and astern directions as well as in the oblique icebreaking mode. Various other operational tests were also included to verify the maneuverability and operational capabilities of the vessels.
The results of the tests proved to be outstanding. Although the ice conditions in the Gulf of Ob were on the upper end of the vessel’s designed icebreaking capability, the Baltika exceeded the required performance targets and expectations with a clear margin. The vessel could break 1.2 metre level ice in continuous motion when proceeding bow first and could achieve a speed exceeding 3 knots when moving astern.
The oblique mode, which had never been tested in real operations before, worked extremely well during the extensive tests on the Kara Sea. In fact, the dynamic positioning system, developed by Navis Engineering, made oblique operations surprisingly simple and straight-forward. In the port of Sabetta, the Baltika demonstrated excellent maneuverability and rubble clearing capability. The vessel also demonstrated its ability to penetrate heavily compressed ice ridges without ramming them.
“Baltika’s voyage to the Gulf of Ob proves the exceptional operational capability of the oblique icebreaker concept in very difficult ice conditions,” Head of Ship Design Mika Hovilainen of Aker Arctic says.
“The vessel could operate in ice conditions that exceeded the design criteria used as the basis of the vessel concept. The Baltika could carry out the same operations as conventional icebreakers with just half of the propulsion power as well as perform maneuvers which are not possible for any other vessel currently in service,” he continues.
Quick facts
- The Baltika is owned by the Federal Agency for Maritime and River Transport of Russia (Rosmorrechflot), and operated by the Russian Maritime Emergency Rescue Service (FGI Gosmorsspassluzhba).
- Baltika is 76.4 metres (251 ft) long overall and 72.1 metres (237 ft) at the waterline, and has a maximum beam of 20.5 metres (67 ft). Her draught at design waterline is 6.3 metres (21 ft) and the corresponding deadweight tonnage 1,150 tons. The diesel-electric power plant consists of three Wärtsilä 9L26 generating sets with a combined output of 9 MW.
- The ship is classified by the Russian Maritime Register of Shipping. Her ice class, Icebreaker 6, requires the vessel to be capable of operating in level ice with a thickness of 1 metre (3.3 ft) in a continuous motion and strengthened for navigation in non-Arctic waters where ice can be up to 1.5 metres (5 ft) thick.
- The vessel is capable of moving in 1-metre (3.3 ft) level ice at 3 knots (5.6 km/h; 3.5 mph) in both ahead and astern directions. When operating in oblique mode, she can open a 50-metre (160 ft) channel in 60-centimetre (2.0 ft) ice. In open water, the service speed of the vessel is 14 knots (26 km/h; 16 mph) and operational range 4,500 nautical miles (8,300 km; 5,200 mi).