ice boat for the south pole

[southern pilgrim]

Several years ago, a man wintered over here at South Pole Station, and built himself an iceboat. He shipped himself a windsurfer rig before station's close in February, built a sled, and took it out onto the skiway in spring. As legend here has it, he went so fast, he broke up the sled and hid the pieces all over the station. I've looked for those pieces for two summer seasons here, and finally found his sail and wishbone boom.
So, I'm going to build an ice boat for this rig, and I need a little help with dimensions. How wide, how long, where to put the mast. The sail is 17' at the luff. I can make all the parts, but looking for basic proportions. I'll send pictures when it's done.
-pilgrim, south pole station

[Rob H]

Do you plan to set it up to *windsurf* on the ice, or do you mean to sit down and sail it as an iceboat?
I've built a couple of windsurfing iceboards. They're real simple,fast and fun, but you need a helmet, elbow and knee pads, or it hurts when you fall.
If that is what you are looking for I can help, but if you want to build a real iceboat,maybe someone else can speak up.

[NormMessinger]

Wow! An iceboat at the South Pole. Just what every boy needs for his last birthday.

I did a google search on "DN Iceboat" and got many hits. That would be a start.

I hope if you pull this off you will share pictures with us.

Best!
--Norm

[Tom Lathrop]

The first "boat" I built was an ice boat in 1959. Being completely innocent of knowlege of either sailing or ice boats in particular, I just built it. Did not even have a picture of an ice boat and had never seen one and no internet either.

Result was that we had a lot of fun with even if it was barely steerable. With a neighborhood kid perched on each runner, it could be made to track fairly well. Finally rammed the dam and busted it up when a gust took over.

With the info that you will be able to find, I'm sure that you will do much better. Keep us posted.

[southern pilgrim]

I'll be sitting down - that sail is huge. Our internet access is over a sketchy satellite pass with bad timing for my work shift hours, so "surfing" is painful like amputations. I feel myself aging between screens, then we lose the connection ... So, chances are I'm making it 18' long skinny and simple, and 12' wide - crossing at about 12 feet in the long axis. Cross, my "buddies" here say, is a suitable shape for this adventure. Placement of the mast is going to make or break this thing, and whether I sit in front of it (to weight the front "steerable, ahem" ski, or behind it and under the center of effort - these are what I'm looking for guidance on.
It can be days between successful online satellite opportunities, so I apologize in advance for delays in responding. And should that center of sail effort be at the junction of the long and cross axis ...

[Iceboy]

Pilgrim, as an Old Antarctic Explorer (1977-80) myself I would be happy to do a little research for you. Please send me an e-mail adress as I could not get your profile to work. I will send stuff as I find it.

JimmyM

[Todd Bradshaw]

Most bow-steering iceboats in that size range would be set-up something like this:

http://albums.photopoint.com/j/View?u=1302883&a=14083578&p=57249426

These are very rough guidelines, but the sail's C.E. is usually located near, or at, the rudder plank (crossbar) area. On most of these boats, you can also reach down to your side from your sailing position and the plank is right there. The combination of the sailor's weight and the C.E.'s position help keep the back end of the boat from skidding sideways (which is a really bad feeling). If you have a means of adjusting the mast base fore and aft a bit, it allows tuning the rig by changing the rake and moving the C.E. to get the best handling.

The bow, steering runner needs a lot less boat and crew weight on it to work. The rig generates considerable downforce, which helps keep it on the ice. If desired, you could probably even shorten the body by 3'-4', up front, and replace that section with something similar to a 2x6 (wide-side-up) sticking forward to make a springboard of sorts to absorb shock for a smoother ride.

Most people who rig sailboard rigs on sit-down iceboats use struts that lead out to the runner plank for keeping the mast upright. It could also be done with plank-mounted shroud wires and a wire out to the bow (the end of the hull, not an added springboard). The sail pivots side to side on it's mast base and the struts or wires support it, but still need to allow it to pivot. It doesn't have to pivot all that much though compared to a sailboat. You are effectively always sailing up-wind in an iceboat (the boatspeed shifts the aparent wind far forward) and the sail is trimmed-in pretty tightly. If the strut system allows you to ease the sail out 40- 45 degrees to the centerline, that's probably plenty.

These rigs often have some sort of bridle/traveler system for the mainsheet. It anchors on either side,out on the plank and connects to the aft end of the wish-bone boom. This type of system is used because it can trim the sail-in closer to the centerline than just having a centerline-mounted mainsheet block on the hull, though that type of mainsheet might be easier to rig and can still work. The section of the hull behind the seat and runner plank doesn't do much. If it's not needed for anchoring the plank, seatback or mainsheet system, it can be cut-off.


[This message has been edited by Todd Bradshaw (edited 12-10-2001).]

[This message has been edited by Todd Bradshaw (edited 12-10-2001).]

[Todd Bradshaw]

In case it helps, I went out and measured our Arrow, which is about the size you are thinking about building. It's a pretty basic, not too extreme, touring iceboat that will hold two people in a side-by-side cockpit that's kind of like the footwell on a laser, only bigger. Basic measurements are as follows:

Hull Length 19' (counting the 41" springboard sticking out from the bow). The front runner is mounted near the springboard's forward end. Our hull gradually widens to about 38" maximum, back at the runner plank/cockpit area.

Runner plank 12' wide, 2" thick, 9" wide in the middle tapering to 7.5" at both ends. It's laminated, solid spruce with about 1.5" of crown glued-in.

The three runners are plate steel, parallelogram-shaped with the corners rounded off, 30" long, 5" high and 3/8" thick. The bottom is ground to a "V"-shaped edge and needs to be pretty sharp. Each runner has a mounting-bolt hole19" back from forward tip. They hang on single bolts through steel chocks so that they can pivot, up and down, when going over bumps.

Springboard 1.75" x5.5" spruce about 70" long, bolted to hull underside, extends 41" forward of hull bow. The original configuration didn't have the springboard, so the boat was 41" shorter and the front runner just passed through the hull's bow. I added the springboard for better stability and a smoother ride.

The distance from the shaft attached to the steering chock (for the bow runner on the forward end of the springboard) to the leading edge of the runner plank14'3".

The cockpit is set up so that your butt when seated is right over the runner plank's forward edge.

Our mast is 18' long, raked somewhat and places the C.E. of the sail about 11" forward of the front edge of the runner plank. The sail is 67.5 sq. ft.plus roach as we have a long boom (8'8"). Your sail probably has a little less area.

Our hull extends about 4' aft of the runner plank as the mainsheet blocks are mounted on the deck. Other than that and the fact that the whole hull is a big, sealed flotation chamber (just in case) the back 4' does nothing.

[This message has been edited by Todd Bradshaw (edited 12-10-2001).]

[Syd MacDonald]

Wow, think of the wind chill at 40 mph!

[Kristian]

That's a good cure for cabin fever! http://media5.hypernet.com/~dick/ubb/biggrin.gif

[Todd Bradshaw]

Wind Chill? We ain't afraid of no stinkin' wind chill.....But you do find out real fast if there are any gaps in your clothing. I always thought iceboaters were crazy - until I tried it. It's so much fun that it's worth getting cold. The last time we got out, there was about a 3" layer of dry, powder snow on top of the ice but it was too cold for it to stick and spoil the sailing. We got the Arrow up to 43 m.p.h. on the GPS, throwing-up a big rooster-tail of snow and wound-up with fresh powder jammed into every possible place.

The time before that, on good ice, the bow runner tossed-up a really small sliver of ice than somehow got inside my full-face helmet visor and hit me hard enough to cut my lip and splatter blood on the inside of the visor. The time before that, the ice was soft on top and we came in with a frozen layer of slush all over our front sides, which looked pretty funny. Even so, it's always worth going out and every good day is remembered for years.

Sometimes it gets chilly but unlike summer sailing, an afternoon iceboating is comprised of several 10-20 minute excursions, punctuated by warm-up breaks and a lot of time B.S.-ing with the other iceboaters. You're not experiencing minus 80 wind chills for long periods of time. You also actually need time between runs to rest your mind and slow down between adrenalin rushes.

We normally have a couple of national-level ice regattas here every winter. Now that I've got a digital camera, I'm hoping to shoot some pictures this year and if I get good ones, I'll post them. Many of the high-end boats are still wood or wood/epoxy/carbon constructions and they are just beautifully built.

[Iceboy]

I'm pretty sure that the pilgrim doesn't sweat the wind chill. 40 below is nothing at the south pole. Average temperature is 55 below without wind chill.

JimmyM

[TomRobb]

My limited understanding of ice boats includes that the forces you must handle are quite large for so small a sail and engineering the machine ought to be up to it. You'll probably need a several block purchase on that sail too, because of the wind loads.
When I was stationed in the arctic in a former life one of the guys built himself a wood sled to run down a nearby hill. Mountain was more like it. He hit a rock or a large bump, went airborne and got a bit banged up, and destroyed the sled, but it kept his mind on something besides the cold, dark, and isolation. The ride was fun too. Brief, but fun. Or so it looked http://media5.hypernet.com/~dick/ubb/biggrin.gif
How is wintering over?

[Bruce Hooke]

For what it's worth, here is a link to the plans for a DN60 iceboat, all on one web page. They're a little hard to read on screen but might do better printed out.

http://www.concentric.net/~Dn4762/specs/dn60.html

Also, to cut down on surfing time, here's a direct link to a site with a lot of iceboating information and links:

http://www.concentric.net/~Dn4762/

[Norske1]

Hello S. Pilgrim. South Pole! WOW! Awesome! Are you really there or somewhere in New Jersey?
How do you keep track of time at the S.P.--or do you pick any time depending on which way your looking North.

How long have you been there and when do you head north?

[Konrad]

Ah, what you need to do is build the Isabella, my friend.

I've built 3 of these, and they are great. You get 80% of the performance of a DN, with only 20% of the time/materials/money invested.

I don't use a windsurfing rig, though. I cannibalized an old Hobie rig. I use the top 1/3 of a Hobie 17 sail and mast. Our best runs were close to 40mph in 15-20 mph winds, measured with a gps.

Here's the page from Bernd Stymer, Swedish designer of the Isabella:
http://www.isabella-iceboat.com/iseng.html

My own page with the Isabella is here:
http://www.geocities.com/bosch_232/January7Ice.html

Norm, you gotta come down to Branched Oak when we do this some time. Bring a clean change of underwear.

[BrianCunningham]

suddenly it doesn't feel so cold out

[southern pilgrim]

Holy Warm Breeze on a Cold Day,
Thanks all for the support on this little secret project. We're having a good session with the satellites, so I reply to all with thanks, then the goods on the sled. First Norske, yes Norske, the south pole. Candy striped pole with the mirror ball on top for real south pole. Ask Jimmy M, who as an Old Antarctic Explorer, has been down here and knows the scoop. This email thing is quite new here for the program, especially from here, but we did put people on the moon about thirty years ago. Custom Skiff's article on the ice is true, and the ship frozen in Marguerite Bay was the Nathaniel B. Palmer and had a bunch of friends aboard. I wintered at Palmer Station, 250? km. north of there. They were frozen when I departed Palmer Station, sailing north across the Drake Passage (boy do I have some pictures of that crossing) for Tierra Del Fuego, en route back here to the Pole. They were still frozen in when I arrived here, 2 weeks later. We are all betting the farm that the two icebreakers headed to McMurdo Sound can break through to McMurdo Station, or most of the circus here will leave the tent. Everything depends on the yearly cargo ship in MacTown. Every steel beam, pencil, brussel sprout, and gallon of fuel is flown by LC-130 (on skiis) here to pole. We just recieved our first two planes in eight days today, as MacTown was hit by perhaps their biggest summer storm ever. They told us the drifts were up to the props of the Hercs. That puts us close to 900,000 lbs of cargo behind schedule already this year. And so that goes ...
But it's the ice boat. I couldn't download the diagrams attached to Tom's posts, and saw they were there after the fact anyway. The body is made, and my hands are still peeling wood glue from laminating a mast. The sled set up will be good, if a bit heavy, and I'm hashing out inset blades in some skiis with a welder. It is the mast which will fail. The only suitably manipulated material here is the Douglas fir from packing crates, some of which is quite beautiful wood. I sliced it into 1/4" pieces, and laminated them with carpenter's glue (best we had), on a slight curve, short of the radical curve of the sail's leading edge. We'll see. If it doesn't work, I'll stick Douglas strips inside a piece of aluminum satellite dish tower, and then bend it. I'm in a bit of a hurry to enter the Christmas Day Race Around the World, an annual south pole event. If the sled goes, I'll be king.
Pictures will come, but don't tell the National Science Foundation, Raytheon Polar Services, or my Mom, before I get a chance to make her go. Thanks for the wisdom and the fun. More to come.

[Kristian]

Do ice boats need ballast?
http://abacus.sj.ipixmedia.com/abc/M28/_EBAY_2a3845eeead0530ffa25e3d596/i-1.JPG

[gert]

I'm not 100% familiar with ice boats but I do hope to build one some day; I am getting the impression there are ski/skate combination runners for them; is this so? And where can one find idiot proof plans for a simple boat for only occasional use? It being a six hour drive from the wet coast to a decent frozen lake that probably has six inches of snow on it. Thx

[This message has been edited by gert (edited 12-21-2001).]

[Ed Harrow]

Southern - keep your eyes open for CTI-Cryogenics refrigerators. I know that we have some down there because I worked with some people from Smithsonian Astro Physics who have the equipment. Somewhere I have a bunch of emails from one of them while he was down there.

Anyway, it's those refrigerators that are keeping the ice under your feet. If they stop running better hope your ice boat floats. http://media5.hypernet.com/~dick/ubb/wink.gif

[Todd Bradshaw]

Most iceboaters have wondered at some point about equipping their boats with skis and sailing on snow but as far as I know, nobody has done it sucessfully yet. I also have iceboating books going back to the 20's and 30's and there are no mentions of ski-runners. Since the runners need to provide tremendous lateral resistance, yet slide forward almost effortlessly, a sharpened blade on ice has the ability to work but a ski-like thing on snow probably won't, especially as the angle of heel varies during sailing.

It also may take too much power to get an iceboat-like craft moving on skis and snow. Think of the difference between pushing-off on ice skates and gliding across the rink and breaking trail through 8"-10" of loose snow on cross-country skis. When iceboating, hitting patches of snow as small as 1" deep can feel like you've hit a spot of glue. We've sailed through fresh powder 2"-3" deep but even after one day of sitting on the ice, it's usually stuck to the surface and the boats won't go until it either melts or gets packed down into snow-ice.

One of the best sources of iceboat information is the book "Think Ice". It's published by the D.N. class association and available from the class for about $15 :
http://sailingsource.com/ice/index.htm
The D.N. isn't very roomy, but parts, plans, and kits are readily available and the boats sail quite well. The book also has a nice two-seat touring version of the boat. Construction is very similar to the stuff we talk about on the forum all the time - spruce, plywood/epoxy, etc. with pre-manufactured, add-on hardware.

As far as the earth-friendly, wind-powered snowmobile goes though, it's a wonderful thought, but I'm not sure it will ever be possible. Ice is nice - but snow is slow....

As a side note, we've got a guy in town who shoots a lot of iceboat pictures from a kite-mounted camera and gets some really neat shots. Check out:
http://www.iceboat.org/Wilson/craig_wilson.htm