Friday, January 21, 2011

the Ice breakers - of course the speciality ships

15,600,000 square kilometers of earth  is glaciated i.e., permanently covered with ice. That ice takes the form of glaciers, ice sheets, or ice caps. There is Arctic and Antarctic which have different geography.  Arctic is an Ocean surrounded by continents; Antarctic is a continent surrounded by ocean.  One has remained uninhabited by humans.

To be in the midst of humans, when in a group either as a participant or on the other side hosting or lecturing a group, the initial moments could be hostile and one of intimidating silence. Confident and experienced persons would be able to cut through and be the path breakers in initiating a discussion or introduction.  This is breaking the ice.   An icebreaker is a facilitation exercise intended to help a group to begin the process of forming themselves into a team. Modern day speakers tend to present some games to warm up and help the participants know each other by focusing and sharing personal information. 

One such exercise is to ask the participants to share a ‘little known fact’ about themselves.  Some times you could see, people flounder to even speak about themselves.  There could be mock interview within smaller groups and then the interviewer introduces the person to the larger audience.  They could be asked to state two truths and a lie.   There list can only keep expanding when you realize that the facilitation is to analyse the group dynamics and make them interact and listen to you. 

This is not about the HR exercise but more about the type of ship known as ‘Ice breakers’.  These have emerged arising out of need and evolved in shape with improvements in ship design and construction.  The ice that covers the sea  is described as first-year ice, which is the one that occurs in the Gulf of St. Lawrence and freezes and thaws within a one-year period. Multi-year ice is ice leftover from previous years that has never melted and is harder than first-year ice. There is also  glacial ice, which is really hard stuff.

Ice breaker is a special purpose built ship designed to move and navigate through ice-covered waters.   For navigating through the ice, the ship would require a strong hull, an ice clearing shape and more power to thrust through ice-covered waters.  Such ships would be required to keep trade routes open where there are seasonal or permanent ice conditions.  

They are expensive to build and more expensive to maintain.  Earlier they were powered by diesel-electric power plant, gas turbines and some by nuclear energy. Conversely, they may not go well in ordinary sea waters as they have thick rounded keels with no protuberance for stability and could even roll in light seas.  When performing their primary function also, they would be uncomfortable to travel as they would wade through continuous thick ice making constant motion, noise and vibration.  Modern vessels would have shielded propellers both at the bow and at the stern, as well as side thrusters; pumps to move water ballast from side to side; and holes on the hull below the waterline to eject air bubbles, all designed to allow an icebreaker stuck amidst thick ice to break free.  Some advanced  icebreakers also carry aircraft to assist in reconnaissance and liaison.

There are ice charts which depict where the heaviest ice is and what the best route for a vessel to take would be.  Those on the rough ice breaking mission could enjoy to see what everyone else would only get to read.  They could see beluga whales, snowy owls, arctic foxes, walrus, polar bears and more.  

For explorations in polar region, these sort of vessels are required.  Early day explorers used wooden and reinforced double planked hull and strengthened cross members with iron wrapping around the outsie.  When ice floes are pushed against the ship, they could cause damages known as nipping.  The kayaks are famous examples of human powered boats with covered deck with double bladed paddle.  Though they could not break the ice, they were light and can go over the ice. 

Over the years, technology has developed and nuclear powered icebreakers of the Soviet made a remarkable impact. Nuclear powered icebreakers are far more powerful than their diesel powered counterparts, and have been constructed by Russia primarily to aid shipping in the frozen Arctic waterways in the north of Siberia.

The first of its kind is NS Lenin launched in 1957 which was both the world's first nuclear powered surface ship and the first nuclear powered civilian vessel. It was  decommissioned in 1989, because its hull had worn thin from ice friction. She was laid up at Atomflot, a base for nuclear icebreakers in Murmansk,  and reportedly was converted into a museum ship.  NS Arktika was the first surface ship to reach the North Pole in 1977.  The Soviets are the pioneers and have mastered this art.

In US ships had been employed to work in harbour ice in the nineteenth century especially in Delaware river.  Years later US Coast Guard contracted to build 216 ft steel hulled Northland touted to be strongest and heaviest steel hull.  This vessel patrolled Alaskan arctic for 11 years but was reported to be slow and poor in handling. 

The nuclear-powered container ship Sevmorput is used to transport barges and containers to the coastline of the northern Siberia.  The name of the vessel, Sevmorput, is a Russian abbreviation  meaning  
Northern Sea Route
.  It was  the first nuclear powered vessel constructed according to the international convention safety requirements for nuclear cargo ships. Sevmorput can carry 1,336 standard 20-foot containers or 74 lighters. The lighter is a special type of seagoing transportation vessel that is utilised for loading and unloading operations in areas where the harbour waters are too shallow to accommodate the container ship, thereby necessitating operations in the open sea.

NS 50 Let Pobedy  is touted to be the largest in the world as of 2007.  Its construction started in 1989 at Leningrad and originally was named NS Ural.  The financial crunch took its stall as also a fire accident on board.  She was finally completed in 2007 and sailed into Gulf of Finland for sea trials in 2007.   This again is reportedly an experimental project with a spoon shaped bow.

Sea with its variety continues to compound us all the time and mankind is continuing its efforts to explore and overwhelm it…

Regards – S. Sampathkumar.
Even a purposefully built vessel would be damaged if it were to collide with an iceberg at a speed.  The much famous ‘tip of ice berg’ is real and a major portion of ice berg would still be under water.    To break through ice, the vessel needs great momentum and power to drive its bow up on the ice, break the ice under its immense weight.  In the act the ship would slow down and the speed is increased by its design to direct the broken ice around or under the vessel.  The external components are at greater risk of damage than the hull itself. 

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