MT Mastera, image courtesy NESTE OIL, click for larger image

Concept and Background

- by Lloyd’s Register’s Robert Hindley and Robert Tustin:

Bow propellers have been installed on ships operating in ice since the 1880s with the following practical effects observed:

• Encourages the ice to break ahead of the ship’s bow
• Ability of propeller to further break-up ice into smaller pieces
• Washing of ice pieces away from the ship’s hull
• Improved maneuverability of the ship in the ice
• Assistance for freeing of the ship in trapped conditions

The practical effects of bow propellers in ice can also be achieved with podded propulsion units, or azimuthing thrusters which, when located at the stern, can be rotated to pull the ship ‘stern first’ with the additional benefits of directional thrust for maneuvering in ice and flushing of ridges.

Notice the transom clears iceline, a stern-facing pilothouse, the laterally located stacks, and the fine stern entry on MT Mastera. Image courtesy NESTE OIL, click for larger image

Ice interaction when operating stern first, courtesy Robert Hindley and Robert Tustin, Lloyd's Register

Ice interaction with propeller and hull operating stern first 

Beneficial effects of stern first operation from propeller and hull ice interactions are shown above and described below:

• Ice sheet bending and breaking – the water flow into the pulling propeller causes a pressure drop under the ice sheet ahead of the stern; which reduces buoyant up thrust on the ice sheet and promotes ice breaking by bending.
• Flushing of ice ridges – by azimuthing the pod adjacent to the keel of an ice ridge the variable flow of water promotes the erosion, or flushing, of the ice ridge keel.
• Lower frictional resistance in ice – with the propeller pulling, the water flow from the propeller washes along the length of the hull. The water flow reduces the friction between the hull and the ice by lubrication.

You may wonder, so does this present a curious rules of the road situation while at night?

Not to worry, “Stern First Ice Class Ships” will have mast head, side, and stern lights for both bow first and stern first operations.

Image courtesy NESTE OIL

Lloyd’s Register announced today that the first dedicated set of rules for stern-first ice-class ships has just been published, answering the demand for technical support as industry continues to explore the potential of polar transportation routes and the new energy reserves in the far north.

“These practical rules are answering a growing demand in the market and include the use of standard operational scenarios to provide designers with a basis for prescriptive rule applications that have been validated with designers and operators of these specialist ships,” said Robert Tustin, Lloyd’s Register’s Technical Manager for New Construction in Asia.

Lloyd’s Register has had a long involvement in the development of this class of ships. Mastera and Tempera – two 106,000 dwt “double-acting” tankers owned by Neste — were built to its class in 2002 and 2003 at Sumitomo’s yard in Japan. The ships were deployed to the Baltic, where they often operate stern first in heavy ice conditions, independent from icebreakers.

Other tankers, such as Sovcomflot’s Mikhael Ulyanov and Kiril Lavrov, were designed and built for operating stern first in ice in the Arctic. These ships, dual classed by Lloyd’s Register and the Russian Maritime Register of Shipping, were designed to eventually shuttle crude from the Prirazlomnoye platform in the Pechora Sea to a floating storage and offloading unit moored off Murmansk.

The development of Lloyd’s Register’s new rules were supported and validated by leading ice-class tanker designers, key regulators and operators.

The interpretation of regulatory and other rule requirements — and validation of strength levels for the hull and propulsion units — were confirmed by a review of the current fleet of double-acting ships, ensuring that practical experience supported the rules’ development.

They offer the following key interpretations:

§         The ship is considered as a bow-first and stern-first vessel for application of ice-class rule requirements for hull and machinery
§         It is also considered as a stern-first ship for the application of navigation-related rules and regulations
§         In other cases, the rule applies to bow-first ships only

The rules also include a framework for alternative-load scenarios when unusual operations are envisaged, as well as interpretations of international regulations and classification rules based upon industry precedents, said Tustin.

In this photo released by Maritime New Zealand, the Russian fishing vessel Sparta is seen in waters in the Ross Sea near Antarctica, Dec. 16, 2011. (AP)

Crew on board the Russian vessel Sparta have requested more equipment to help repair damage to the boat’s hull while rescue efforts are hampered by icy conditions in the southern ocean.

Sparta issued a distress call around 3am on Friday from a position next to the Antarctic ice shelf, about 2000 nautical miles (3704 kilometres) south east of New Zealand.

The 48m vessel, with 32 crew on board, had hit ice and put a 30cm hole in the hull, 1.5m below the water line. It was taking on water and listing 13 degrees.

The Rescue Coordination Centre New Zealand (RCCNZ) tasked three nearby vessels to assist Sparta, but all three have been hampered by heavy sea ice.

One, the New Zealand vessel San Aspiring, was released from the rescue yesterday after its crew determined the more than 470 nautical mile (NM) journey was too dangerous.

The Norwegian vessel Sel Jevaer is only 19NM away but is currently hemmed in by ice and unable to proceed. Sparta’s sister ship, Chiyo Maru no. 3 is slowly making its way towards the stricken vessel but is still days away.

Yesterday, a Royal New Zealand Air Force (RNZAF) C130 Hercules dropped extra pumping equipment and fuel to the vessel, after a seven-hour flight from Christchurch.

The Hercules was returning today and due back in New Zealand tonight.

RCCNZ Search and Rescue Mission Coordinator Neville Blakemore said the crew was continuing to pump water from the ship using the on-board pumping equipment and the one delivered yesterday.

“They are keeping ahead of the water ingress using two pumps,” Mr Blakemore said.

“But they are having difficulty in trying to fix a patch to the damaged part of the hull because they need to stop one of the pumps to do this, and then the water level creeps up again.”

Mr Blakemore said Sparta’s stability was currently the number one priority for the rescue operation.
“With help days away at least, we need to keep the crew on board Sparta where they have their best chance of survival.

“The crew has manoeuvred the vessel alongside the ice shelf and attached mooring lines to the ice. They have also deployed their life rafts which are alongside Sparta.

“They have told us they need more equipment to assist with repairs and securing the vessel.”

Mr Blakemore said the ship’s agent was sourcing the equipment and RCCNZ would coordinate its delivery.

Sparta’s owner has commissioned the South Korean icebreaker Araon to go to Sparta to offer assistance. Araon left New Zealand just after midnight and is expected to take about eight days to reach Sparta.

Weather conditions in the area remain calm.

Launched in Saint Petersburg Russia the NS Ural was not actually commissioned until 2007. By that time it had a new name, the NS Let Pobedy, and a new designation the largest nuclear icebreaker in the world.

The vessel is impressive with an overall length of 521 feet, capacity for 138 persons and service bays carrying two Ka-32 helicopters. But the size of this vessel barely seems to be enough to float it’s two greatest assets; a pair of nuclear reactors capable of producing over 55 megawatts of power and over 25,000 tons of displacement which, combined, allow the Pobedy to break through sheets of ice up 9 feet thick.

To put that in perspective just 15 inches of ice is needed to safely support a 10 ton truck while the USCGC Polar Sea, the first American surface vessel to reach the North Pole, has 6 feet of ice crush capability.

In all Russia built 10 purpose built nuclear icebreakers with seven classed for ocean service and two classed for river duty. The country also built a commercial nuclear icebreaker, the NS Yamal, which was planned to be converted to an exploratory drillship but is now being prepared for use as an arctic cruise ship.

Just in from the Associated Press…

MOSCOW – A Russian icebreaker labored Monday through howling winds and heavy snow as it tried to reach icebound ships in the Sea of Okhotsk where more than 500 seamen are trapped.

Three of the vessels have been trapped since Friday in ice estimated to be two meters (6 1/2 feet) thick. The state news agency RIA Novosti said two more ships became stuck on Monday.

The Sea of Okhotsk is an arm of the northern Pacific to the west of Russia’s Kamchatka Peninsula.

A statement from the Transport Ministry said there was no immediate danger to the crew on the three ships stuck since last week, who have sufficient food and water. The Ministry said an icebreaker was expected to reach their vicinity early Tuesday.

RIA Novosti cited a local coast guard official as saying winds on the sea were up to 30 meters per second (more than 65 mph).

The three ships that have been trapped since Friday — a fishing vessel, a refrigerated freighter and a scientific research ship — are in a tight convoy. The two others are about 20 nautical miles (35 kilometers) away.

Distress signals have been received from the Sodruzhestvo fishing mother ship and the Professor Kizevetter scientific research vessel. All their attempts to get to the clear water have failed, the state sea rescue coordination centre reported.

The temperature in the area is 22 degrees below zero, and according to the forecast, it will fall lower. It may complicate the situation more and hold the vessel in the ice trap for a long time.

The grey-white ice is up to 30 centimetres thick. A distress stage and the rescue operation beginning have been declared in the region. The sea rescue tugboats Irbis, Predanny and Rubin have left for the area to evacuate people. One of them is expected to approach the edge of the ice on Friday evening. The rest are expected to come there on January 2.

According to the Yuzhno-Sakhalinsk sea rescue coordination centre (the coordinator of the rescue operation), the Sodruzhestvo, the Bereg Nadezhdy transport refrigerator and the Professor Kizevetter scientific research vessel (all are from the port of Vladivostok) are in the worst situation. They are blocked in the ice 11-12 miles away from the mainland coast. In the sea ice trap are also the fishing and transport ships Tumnin, Ostrov Karaginsky, Amursky Liman, Komsomolets Kaliningrada, Pamyat Kirova, Gennady Volodarsky and Alexander Belyakov. They are from the ports of Nakhodka, Vladivostok, Sovgavan, Petropavlovsk-Kamchatsky, St. Petersburg and Murmansk.

Source: TACC

More than three decades ago, marine scientists in the United States first identified the need for a research vessel capable of bringing scientists to Alaska’s icy northern waters.

The University of Alaska Fairbanks has announced its intent to award a $123 million contract that will meet that need. The university has selected Marinette Marine Corporation of Marinette, Wis. to build the 254-foot Alaska Region Research Vessel. When complete, the vessel will be one of the most advanced university research vessels in the world and will be capable of breaking ice up to 2.5 feet thick. According to project leaders, the ARRV’s home port will be in Alaska, most likely at UAF’s Seward Marine Center.

The $123 million for the ship construction contract is funded entirely by the American Recovery and Reinvestment Act. The total cost for the project is $200 million.

The vessel will be owned by the National Science Foundation and operated by UAF as part of the U.S. academic research fleet. It will be used by scientists in the U.S. and international oceanographic community through the University-National Oceanographic Laboratory System. The vessel was designed by The Glosten Associates, a marine architecture firm in Seattle.

After the ship has been completed, the crew will take the vessel from the shipyard through the Great Lakes-St. Lawrence Seaway transit system and the Panama Canal to Alaska in 2013. While in transit, scientists and crewmembers will test the scientific components of the ship in preparation for unrestricted science operations beginning in 2014.

Here is a shot from LTJG Tasha Thomas (HEALY’s Public Affairs Officer) in one of her regular updates to family and friends about life aboard the icebreaker HEALY. This shot was taken during the Bering Sea Ecosystem Expedition – an expedition from April 4–May 11, 2009, where a team of scientists from the Polar Discovery team will be aboard the Healy in the Bering Sea and will focus on learning about sea ice, and how climate change will affect it.

According to the Polar Discovery website:

Going on the ice is pretty special. Even on the icebreaker Healy, only people with a work-related reason are allowed to leave the ship when we stop at an ice station. That means the only people who usually go on the ice are the polar bear watch, the rescue swimmer, the writer and the photographer (us), and up to a dozen or so scientists.

But every now and then, on a particularly nice day, with particularly thick ice, something special happens: Ice liberty.

So what do you do when they let you on the ice? Play kickball. The first balls to emerge were soccer balls, but a relatively small area had been marked safe for ice liberty, and we didn’t want a ball that would go far. Instead: the big green exercise ball from the gym. It still kept blowing out of bounds, where the rescue swimmer or polar bear watch had to retrieve it.

You can learn more about the Bering Sea Ecostem Expeditions and check out more photos from the Bering Sea HERE.

So the cruise ship industry may be able to offer the lowest prices in 20 years, but one thing that they cannot control is the weather and unfortunately passengers usually have to find this out the hardway.  Well that was the case anyway for the some 300 passengers aboard the CTMA-Vacancier that got stuck in thick ice for nearly 24 hrs in the mouth St. Lawrence River.  Canadian Coast Guard ice breaker “Terry Fox” finally made it to the stranded cruise ship following getting stuck itself in the thick ice.

Further reports are saying that two more vessels, including a ferry and cargo ship, have been stuck in the thick ice as well.  As for the passengers aboard the Vacancier, they don’t seem to mind the short delay and have said that “it’s a 24-hour party on board.”

Image Source: CTV.ca