Ice Breaking

[The Pipe]

Prop damage is probably the major issue with any boat used in ice breaking, the sound of cracking ice is nice but not followed by clattering blades!

[NB Alnwick]

Like all things to do with boating - a lot depends on how the boat is handled - pulling a boat through the ice on a long line is bound to damage the hull around the water line. That is why so many wooden boats (horse drawn) incurred ice damage. Pushing a boat along with power on is very different - ice is rigid and brittle and the boat seems to raise the level of the water well before it and this sends cracks through the ice in all directions ahead of the boat. Similarly, when a motor boat is under power, the water level beside the boat drops to lower than normal and, in ice, this rapid change of level causes the ice to break up rapidly and noisily. For the most part, when pushing through ice, the ice that comes into contact with the hull has already been broken into small pieces that, for the most part, float harmlessly past.

 

I will agree that damage to the propulsion gear is a risk - we have a heavy slow running engine, gearbox and prop that many would say is too big for a narrow boat. So far it has proved to be sufficiently robust but we don't take unnecessary risks and this is why I said that I avoid reversing in ice. When moving forward under power, the prop is submerged well below the ice.

 

Given the choice I would not choose to move the boat in ice thicker than half an inch or so but when needs must we have broken ice up to four inches thick and usually make the journey in more or less the same time as when the cut is ice free - certainly when moving through ice, we never had to queue for locks . . .

Edited December 12, 2011 by NB Alnwick

[Martin Megson]

Well that started a debate. As a newcomer I was worried about the blacking but there is no sign of damage. As for reversing I didn't actually reverse the boat but simply gave the engine a quick blast in reverse which pushed water under the boat which broke the ice as it lifted it alongside. I agree with NB Alnwick's last post - the thin ice is pretty well broken up before the bow touches it.

[Mitchell]

Stupid question alart , what happens if you get to the lock . Its half full /full and theres a layer of ice , do you just empty it as normal and let the ice brake under its own weight and fall into the bottom?

[ditchcrawler]

Stupid question alart , what happens if you get to the lock . Its half full /full and theres a layer of ice , do you just empty it as normal and let the ice brake under its own weight and fall into the bottom?

Then you get your pole out and move it from behind the gates so you can get the gates open.

[alan_fincher]

Stupid question alart , what happens if you get to the lock . Its half full /full and theres a layer of ice , do you just empty it as normal and let the ice brake under its own weight and fall into the bottom?

Not a stupid question at all!

 

Fortunately locks are often the very last thing to ice up completely in my experience, as many leak enough to create the small flows of water that slow down the process.

 

Also I think chill winds help cause the ice to form on canal surfaces, so water in an empty or part full lock, at least, with all gates closed, will be amongst the last to freeze over.

 

In my relatively limited experience, by far the biggest problem can be trying to get enough broken ice from behind gates that you can get them fully open to get a boat in or out.

 

For example, once you have ice blocking the lower gates of a narrow lock, (and you may have brought a lot in with you), and you have a boat in waiting to leave, it can get really complicated. Just reaching the ice with anything to pull it out of the way may be hard, and if you are using the front of a boat as a platform, it means there isn't really any space to draw large chunks of ice back in to.

 

You can end up trying to get gates open enough, that you are then trying to hook ice out from behind the gates, but push it around, and relatively out of the way through the part open gates.

 

Make no mistake, when there is thick ice to contend with locks are hard work - even broad ones, where you at least have the option of only part opening both gates, and using the gap in the middle.

 

And of course every gate you cross may itself be like a skating rink.......

[alan_fincher]

Pushing a boat along with power on is very different - ice is rigid and brittle and the boat seems to raise the level of the water well before it and this sends cracks through the ice in all directions ahead of the boat. Similarly, when a motor boat is under power, the water level beside the boat drops to lower than normal and, in ice, this rapid change of level causes the ice to break up rapidly and noisily. For the most part, when pushing through ice, the ice that comes into contact with the hull has already been broken into small pieces that, for the most part, float harmlessly past.

Interesting observations, but I'm not convinced at all the case sometimes when the ice is thick.

 

There are several published videos on YouTube of "Sickle" breaking ice before we owned her, not limited to the ones I have put here, and while they are not that high definition, the only real evidence I can see of ice breaking much ahead of the boat is where large slabs are actively being pushed forward by the boat, and that is breaking stuff a few feet ahead of the bow.

 

Sickle was actually specifically converted to an ice-breaker, and has a big engine and big blades, (but clearly not the unusually high torque of "Alnwick"), but is still visibly being regularly brought to a halt by the ice, and having to reverse up and "charge" it. When it does, the bow can often be seen trying to ride on top of it, and the ice is then weakened and breaks because of the added downward weight of the boat, with the bow then dipping down a bit.

 

Other purpose built ice-breakers, including towed ones, were often designed in a way that deliberately encouraged the bow to try and ride up.

 

You are lucky with Alnwick - most ex working boats I have seen, included those well loaded, tend not to simply be able to keep carrying on, and do need a periodic reverse and run at it in the worst parts. If the thick ice is regularly bringing 20 tons of boat under full power to a complete stop, I still can't see how all the blacking is going to survive the experience, but it seems many don't agree with me!

[NB Alnwick]

The only problem that we have had with locks during severe cold weather, is ice on the ground around the lock and on the gate tops which requires much greater care walking around and over the locks. This is not a good time to try jumping across or climbing up lock gates

 

As for ice behind the lock gates, we have always found that the ices moves away quite easily when the gate starts to open and we engage forward gear - but then our boat is only 62ft long so there is plenty of room for it to move about. I was manning Alnwick single handed in the worst conditions that I ever encountered at locks and the only real problem was my own nervousness climbing on and off the boat in slippery conditions!

 

I think those who have done it themselves will understand what I mean . . .

 

I think if the ice was ever so thick that it could bring a 20 ton boat to a dead stop, then I would probably give up and wait for a bit of a thaw! I think that reversing back and ramming solid ice - even trying to ride up on it (that would be difficult bearing in mind how deep we are at the bow) would be a bit like banging my head against a brick wall

Edited December 12, 2011 by NB Alnwick

[NB Alnwick]

For all that has been said, on Sunday, 17th January 2010, we started our engine at 11:00 and navigated through ice that was as thick as four inches in places through three locks to Banbury where we tied up at 13:00 on the same day. The distance travelled is recorded in our log book as four miles.

Our arrival in Banbury as the first boat to move in more than two weeks was recorded by a local journalist (who took the photograph shown earlier in this topic) and we didn't damage our blacking. Unfortunately, we did do quite a bit of damage to the snowman that had been built on the canal near Banbury! And I think we gave a couple of ice skaters quite a shock as we came into site round the last corner . . .

[alan_fincher]

Possibly the Ministry of War Transport should have had the insight in 1942 to build themselves a fleet of 5 "Alnwicks" to keep canal traffic flowing, rather than converting "Sickle" and 4 similar boats

 

Anyway, bedtime, I think!

 

[NB Alnwick]

Possibly the Ministry of War Transport should have had the insight in 1942 to build themselves a fleet of 5 "Alnwicks" to keep canal traffic flowing, rather than converting "Sickle" and 4 similar boats

 

Anyway, bedtime, I think!

 

 

They couldn't afford it

[alan_fincher]

They couldn't afford it

I heard the story that they could have, but were nervous about protracted breaking of ice knocking the rivets off!

 

Good night!

[ditchcrawler]

For all that has been said, on Sunday, 17th January 2010, we started our engine at 11:00 and navigated through ice that was as thick as four inches in places through three locks to Banbury where we tied up at 13:00 on the same day. The distance travelled is recorded in our log book as four miles.

Our arrival in Banbury as the first boat to move in more than two weeks was recorded by a local journalist (who took the photograph shown earlier in this topic) and we didn't damage our blacking. Unfortunately, we did do quite a bit of damage to the snowman that had been built on the canal near Banbury! And I think we gave a couple of ice skaters quite a shock as we came into site round the last corner . . .

You had more luck than Mykaskin then. Victoria didn't get along so well.

[mykaskin]

You can sometimes paint yourself into a corner, breaking more ice around the stern helps. The real trick with corners though is turn early, and use more power to push the stern around hopefully breaking the ice as you go.

[furnessvale]

 

Given the choice I would not choose to move the boat in ice thicker than half an inch or so but when needs must we have broken ice up to four inches thick and usually make the journey in more or less the same time as when the cut is ice free - certainly when moving through ice, we never had to queue for locks . . .

 

Wow! That Alnwick is some boat! 4" thick ice and it doesn't even slow down or harm the blacking. My purpose built icebreaker SANDBACH definitely slows down and loses blacking in such conditions.

 

As Alan said, forget Sickle et al., the ministry should have built a fleet of Alnwicks.

 

George ex nb Alton retired

[NB Alnwick]

Wow! That Alnwick is some boat! 4" thick ice and it doesn't even slow down or harm the blacking. My purpose built icebreaker SANDBACH definitely slows down and loses blacking in such conditions.

 

As Alan said, forget Sickle et al., the ministry should have built a fleet of Alnwicks.

 

George ex nb Alton retired

 

As I said earlier - it would have been too expensive. Kelvin K3s, like ours, were supplied to the ministry during the Second World War but at a price - in those days, well over a £1,000 including the gearbox and associated equipment. Some were fitted to Thames Barges and I think some were used by the Royal Navy but the majority were used in North Sea fishing boats. I think you may have been able to buy nearly half a dozen Listers for the price of a Kelvin!

 

Not that I mean to say anything derogatory about Listers - when we were looking for a boat to buy back in 2005, our first choice of engine was a JP3. We changed our minds when Phil Trotter talked us through Alnwick's build records . . .

[sebrof]

Nope, it means you are leaving the bare scratches and patches for the long time between docking, how long do you leave it 5, 10 years ?

 

Only if you are an idiot.

 

With epoxy, an annual inspection, and repair of any scrapes, should ensure a very long life. But there won't be many scrapes; it's incredibly strong stuff.

[Proper Job]

This was Ocelot a few Winters back.

 

 

At this point it was only an inch or so thick. Not far on from here it became > 4".

 

At the time, the blacking on Ocelot was 2/3 years old and it did remove it on the bow. The sides were fine.

[bargemast]

Breaking the ice is no problem in general, with or without damaging the blacking, the only boats that have to be very careful doing this, are the ones made of iron, as iron doesn't dent, and becomes more brittle in the winter, so the iron risks to crack if you come to an abrubt stop in too thick ice.

 

Peter.

[jonny]

Possibly the Ministry of War Transport should have had the insight in 1942 to build themselves a fleet of 5 "Alnwicks" to keep canal traffic flowing, rather than converting "Sickle" and 4 similar boats

 

Anyway, bedtime, I think!

 

we've also done a bit of ice breaking, but when we were moored in a marina you wern't allowed to move when there was ice!!

 

the reason given was that it could damage the GRP boats, Is this not the same as on the Main line?

 

Could you not sink a GRP with a big sheath of ice? and indeed would you know if you had?

[FadeToScarlet]

Depends who you believe, Phyllis will insist that you won't damage the GRP boat, others will disagree.

[jonny]

Depends who you believe, Phyllis will insist that you won't damage the GRP boat, others will disagree.

If I owned a GRP boat and saw a narrow boat breaking ice, coming towards me I think I'd be a little worried especially if the ice was quite thick.

 

Iv'e seen sheets of ice thrust to the banks with great force, surely one of these sheets is capeble of severe damage to a GRP.

[furnessvale]

If I owned a GRP boat and saw a narrow boat breaking ice, coming towards me I think I'd be a little worried especially if the ice was quite thick.

 

Iv'e seen sheets of ice thrust to the banks with great force, surely one of these sheets is capeble of severe damage to a GRP.

 

If you owned a GRP boat you would, of course, have no need to worry as you will have taken the precaution, as all GRP owners do (NOT), of laying down ice boards to protect the hull.

 

In truth very, very few do this and most prefer to moan at any passing boat that dares to move 1mm of ice.

 

George ex nb Alton retired

[bargemast]

If I owned a GRP boat and saw a narrow boat breaking ice, coming towards me I think I'd be a little worried especially if the ice was quite thick.

 

Iv'e seen sheets of ice thrust to the banks with great force, surely one of these sheets is capeble of severe damage to a GRP.

 

 

Probably better to worry if the ice is really thin, as it can cut like a nife through a GRP boat if you're unlucky.

 

Peter.

[Laurence Hogg]

I guess it depends on the quality of the blacking - we often break through ice and the picture below was taken after we had made the four mile journey from Cropredy to Banbury breaking through virgin ice all the way - often as thick as four inches - no blacking lost on our boat and no complaints from those who were freed from their ice-bound state as a result of our efforts . . .

 

Cracking picture - thats the way to do it!

 

Cracking picture - thats the way to do it!

 

Also our blacking doesnt come off in ice either, but ours is B&Q proffesional exterior gloss black which so far has proved a very superior paint to use! Applied straight onto freshly blasted iron and steel, 2 coats.