Zurich, Switzerland headquartered, ABB Group reports they “will provide the power, automation and turbocharging capabilities for the most advanced port icebreaker ever built.”
The Russian built ship’s configuration is unusual, described as “a totally new concept especially developed for heavy harbour ice conditions with extensive thick brash ice.” It has four 3 MegaWatt Azipod units with two in the stern and two at the bow.
Sounds like this configuration might permit the ship to be used as an oblique icebreaker, allowing it to clear a channel wider than the ship’s beam.
Tups, who seems to be our resident icebreaker expert, brought this to my attention. He feels this type of icebreaker may be appropriate for the Great Lakes. He notes that the new Russian icebreaker is “slightly bigger than USCGC Mackinaw…about 50 ft longer, 10 ft wider, 5 ft deeper and about twice as powerful.”
While the vessel’s propulsion system is capable of pushing it sideways in broken ice, the hull is symmetrical like in a normal ship and thus does not allow sideways icebreaking in any meaningful ice thickness. In the oblique icebreaker, the sloping “icebreaker” side is inclined to about 45 degrees from keel to waterline whereas this has a more “shipshape” hull. However, if this vessel was fitted with a hatch at the waterline and a built-in oil skimmer, it could move sideways in open water and use the hull to direct the oil slick floating on the water surface to the recovery chamber.
As for the future Great Lakes icebreaker, I’m not sure if this particular kind of icebreaker (four azimuth thrusters) would be the most optimal solution for the US Coast Guard as it is designed for somewhat different operating conditions. However, the technology (DC grid, small Azipod units) would be excellent for an icebreaking vessel of that size. While USCGC Mackinaw already has Azipod propulsion, that particular Azipod type is no longer offered by ABB and the next size category (VI1600) would probably be too large. The new small units have other advantages as well, such as permanent magnet motors directly cooled to the surrounding water.
If I was given free hands for designing a Great Lakes icebreaker, I would probably go for a symmetric hull with three azimuth thruster units, one of which is located in the bow of the vessel. Three such vessels are already under construction in Finland (1) and Russia (2). This would give excellent icebreaking capability in both level ice and broken ice (channels, ridges) as well as maneuverability when assisting other vessels. It would also have acceptable open water characteristics and station keeping capability, making it suitable for e.g. buoy tender work during the summer season. As for size, it’s difficult to say without any background work or idea about what kind of performance is required in the Great Lakes, but I’m sure it would be smaller than the Russian port icebreaker presented here but perhaps somewhat larger and more powerful than the Mackinaw. Of course, that would be a solution that prioritizes icebreaking operations and I’m not sure if that’s what the USCG would actually want even if they were given extra funding for an “icebreaker”.
Of course, a “true” oblique icebreaker would always be an option, but such vessel would inevitably be larger and more expensive than a more conventional design. However, if it came to a choice between “the old Mackinaw” (an icebreaker too large to ever leave the Great Lakes) and a ship that can provide the same performance (wide channel) and yet fit through the locks, I would of course go for the asymmetric icebreaker. It’s already proven technology.
The construction begins today:
There’s a minor mistake in the article. The propulsion power is actually 12 MW (4 x 3 MW).
The hull of the port icebreaker is slowly taking shape in Russia:
Ob was launched today:
There’s a good set of photographs showing the underwater hull.
Tups, thanks, great photos. In many respects looks like a very simple design, almost barge like.
We probably could use something like this. Perhaps as you say a bit smaller with three propulsion units instead of four.
Ob is due to leave for sea trials in a few days – some photographs of the fairly standard Russian-built civilian icebreaker from inside and outside:
…and now it’s completed:
@Tups, Thanks, very interesting.