Arctic use/reinforcing for ice/"expedition class"

Something i'm curious about, what kind of hull changes are normally made if a vessel is being designed to literally sail to the arctic, antarctica, and similar "extreme" conditions (like south of the 50th parallel)?

I mean obviously I assume it will be thicker, stronger, and so forth, but are there specific standards? Wood hulls would be suggested to be a minimum thickness, steel hulls a certain minimum thickness vs something only for use at the equator, global strength upgrades assuming a much worse normal sea state (and what minimum sea state would they usually be designed for), etc.

I'm curious how much weight, cost, and other compromise is involved in making a ship seaworthy in these extremes. (and yes i'm aware one would normally never venture south of the 40th without a seriously large and stout ship either, this is more for curiosity's sake)


Bonus points for opinions on "whats the smallest ship that you personally would feel safe on sailing or motoring to antarctica with?"

 

It depends on what ice class you want the boat certified too. Take a look at http://www.iacs.org.uk/document/public/Publications/Unified_requirements/PDF/UR_I_pdf410.pdf . The higher the class you want to qualify for the more tradeoffs you have to make. At some point it is hard to quantify exactly what tradeoffs had to be made because the boats are designed from the keel up as fundamentally different vessels.

What ship I would take depends on where I am leaving from and where I am going. But any vessel certified to appropriate levels for the conditions I was in would be fine by me. Probably starting at around 40', anything smaller gets cramped for duration cruising, and there is a real chance of getting stuck even in low ice forces ted conditions.

 

No need to invent a boat...the british surf launch lifeboats have passed thru the Northwest passage many times.

Study these boats


sube imagenes



subir fotos a internet

 

There is another approach....shape the ship to avoid crushing, rather than oppose it (and how powerful is ice with an ocean behind it?). The FRAM, one of Amundsen's ships, had a round bottom and retractable rudder and screw. Not a good ride in a seaway, but when caught in ice it gets squeezed up and over the surface rather than crushed. Mind you, it was a SOLID boat as well, so a combination of both strength and shape is needed. Good cargo capacity too, from this shape...pack lots of bikkies and whisky and cards. Marquetry chessboard pattern on foredeck for penguin chess; polar bear optional. Mental note...only wear steel tuxedo for this game!



https://en.wikipedia.org/wiki/Fram
http://www.coolantarctica.com/Antarctica fact file/History/antarctic_ships/fram.htm
http://www.frammuseum.no/Visit-the-Museum/Fram.aspx

 

To safely pass you simply need construction designed for ocean passages.

A low powered small craft is not going to double as an ice breaker. If you get caught in the ice you stay .

You do need protected appendages, waterproof collision bulkheads, the ability to beach the boat , redundancy and long range fuel and supplies

Steel would be a good choice for a new build.

A secondhand lifeboat would be the best choice. These boats are very rugged, very well designed, very well fit out and very well built.

 

The only time I have been in ice was up the Tracy Arm glacier in Alaska on a 40ft grp motorboat. To move through the broken ice (maybe 6in thick?) the skipper would select a nice flat piece, get behind it and then use it as a battering ram to push the other floes away as we moved forward. That way the boat did not brush against ice, the floe he had chosen did.

The boat itself had a watertight bulkhead some way behind the cutwater and the bow had a reinforcing structure between stem and bulkhead. There were twin engines and both props were well protected in tunnels. Damaging the props with ice was the biggest fear

My brother in law was caught in a storm in ice on his ro-ro ship off NE Canada. The ice floes washing across the decks broke off the swan necks for the water and fuel so even though the ship was still nominally intact they had to seek shelter for repairs

Richard Woods of Woods Designs

www.sailingcatamarans.com

 

I also think you should have good reasons to travel south of 40 deg North. Better stay where the weather is nice and cold.

When the ice was medium thick in the Gulf of Bottnia, sea weather reports on the radio used to say that "ships with ice class 1A or better may claim assistance from the ice breakers." Later in wintertime, the ice wins and not even the icebreakers can keep the harbours in the inner Gulf of Bottnia open. Ice class 1 A would be a start; don't know what it really means. On the other hand, it seems like the icebreakers (with proper ice-breaker names like Odin and Ymer) would be the ships to choose. During the summer season, they are often used for scientific expeditions to the Arctic or Antarctic.
Erik

 

When i was a kid..about 12 years old ...i captained an ice breaker. Everry afternoon after school.

The breaker was a heavy wood skiff , seagull powered, with galvanized steel flashings on the stem and chines.

To break thru the heavy stuff you would trim stern down, give the seagull full power, then launch up onto the ice sheet.
Once on the sheet you would back off on the seagulls throttle, waite for the two stroke smoke fog to thin , then shift weight forward...jump up and down, break thru the ice...then repeat.

When the ice got really heavy you would launch up on the sheet , then take a long steel pipe and punch thru till the sheet colapsed.

 

Plenty of small yachts (25-60ft) have been down to antartctica, you have to be careful with the ice but it is very do-able.

I was just down there on a 60 foot steel Ketch. Stout boat but nothing special, many of the Antarctic charter yachts are older steel or aluminum boats designed for various around the world races. After being down there I would feel comfortable going down to the antarctic pennisula in any well sorted offshore boat. The only reason I would not want to go down in our current 28 ft boat is that she has no engine and working through ice would be very difficult without. However, Tim and Pauline Carr went down in an old wooden boat without motor, so it is possible, bit would limit where you could go.

Going into pack ice is a completely different game though...

 

Question from a tropical guy; Why would anyone want to go to Antarctica? The place is barren, miserably uncomfortable and fraught with danger.

Scientific research people, OK. They have a reason to be there despite the misery, isolation, and...oh yeah, danger.

At about 5 degrees lat there is a collossal hole in the ice that is 2820 meters deep. Bed rock is at the bottom of the hole. There is a research station on stilts, on top of the hole. There are 86 cables dispersed such that they go down into the hole. Each cable has basketball sized globes that collectively contain 5160 optical sensors. In the deep core there are eight cables spaced so that they are optimized for lower energies and there are 480 of the basketballs that aim at this objective. What the hell are they looking for? Neutrinos. The whole layout has the thoroughly appropriate name; Ice Cube.

Aside from searching for neutrinos, why else would anyone want to be there? I'll bet that those recently rescued tourist people have jolly well had enough of Antartica depite their legitimate claim to temporary fame.

 

Antarctic cruises are popular, not sure how close they get though.

 

Crazy people seeking fame and bar room stories.

Same with the NW passage.

If authorities were smart they would restrict tourism in the area by requiring that the boat put up a bond..say half million dollars...to cover any rescue or environmental damage the tourist cause

 

Point of fact, it was Fridhof (sp?) Nansen's ship specifically designed for a drift attempt at reaching the North Pole. Amundsen borrowed it off of Nansen to take his party to Antarctica for his attempt to reach the South Pole.

PDW

 

Interesting to note that the Soviet-era nuclear icebreakers never ventured to the Antarctic, their nuclear reactors required cold water for cooling, which made a journey through tropical waters too difficult.

 

It should be possible to shut down the reactors and tow the icebreaker with large tug over the areas with too warm water. Or upgrade the heat exchanger to work in warmer water. After all nuclear powered aircraft carriers and submarines operate just fine in tropical waters.