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tickler View Drop Down
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Post Options Post Options   Quote tickler Quote  Post ReplyReply Direct Link To This Post Topic: V Twin
    Posted: 26 Apr 12 at 6:00pm
Originally posted by johnreekie1980

Dingy sailing is not a hazardous sport. If sailing is a hazardous sport then what is cycling to work. The Department for Transport shows 970 cyclists killed or seriously injured in the third quarter of 2011. I am not sure what the definition of seriously injured is but it is probably not sore hands. I have yet to see a figure for killed or seriously injured per mile sailed against other sports but i would bet that it is low.


I hardly mean hazard as in 'death hazard' (although being upside down in a rough sea is not something I relish) If you prune roses there is a pricking hazard, if you sail there is a getting cold and wet hazard.
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Post Options Post Options   Quote I luv Wight Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 5:32pm
There have been attempts to 'improve' the Optimist, by false floors etc to avoid bailing out with a bucket, but it makes it more difficult - the board is higher, it wants to turtle, it's hard to get in over the side when it's floating high when it's upright again

http://www.bloodaxeboats.co.uk
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Post Options Post Options   Quote oldarn Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 4:47pm
Originally posted by Steve Clark


You need to reduce the effective beam when the boat is upside down. This is best done with flooding tubes, which will allow the side you are standing on to sink and thus allow the boat to roll.  You also want the one that is going up top drain. 
 so it isn't hard to find a solution you like.


There is no solution I would like other than not to go there in the first place. I don't know whether you sail a Garda Class, though most likely a cat, but why can't we accept that turning turtle for multi-sailed dinghies with rigging and clutter is the most dangerous situation so why do so many accept it. Perhaps they don't realise that it was seldom the norm pre the asymmetric bubble and other than for cats has only come about as a result of many dreadful badly designed dinghies. I'm amazed that so many sailors of the flat water Garda Classes accept that a dinghy should turn turtle after say a half minute  for reasons of safety.
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Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 4:36pm
Steve, have you found whether flooding tubes provides any assistance with the rig to windward righting problem?
All sorts of things get easier if you can right the boat with the rig upwind, and it occurs to be that an empty leeward tank and a temporarily full windward tank might provide enough time to scramble across the boat...
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Post Options Post Options   Quote Steve Clark Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 4:04pm
Inverted stability is the gnarly downside of upright stability.  But here are solutions short of helium balloons.
You need to reduce the effective beam when the boat is upside down. This is best done with flooding tubes, which will allow the side you are standing on to sink and thus allow the boat to roll.  You also want the one that is going up top drain.  This has been done a number of times in the past, so it isn't hard to find a solution you like.
Just a suggestion from one who has been there and done that.
SHC



Edited by Steve Clark - 26 Apr 12 at 4:05pm
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Post Options Post Options   Quote johnreekie1980 Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 4:02pm
Dingy sailing is not a hazardous sport. If sailing is a hazardous sport then what is cycling to work. The Department for Transport shows 970 cyclists killed or seriously injured in the third quarter of 2011. I am not sure what the definition of seriously injured is but it is probably not sore hands. I have yet to see a figure for killed or seriously injured per mile sailed against other sports but i would bet that it is low.
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Post Options Post Options   Quote oldarn Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 3:53pm
Originally posted by Do Different

As GRF has seen the performance he hoped for albeit briefly. I would expect a man of his independent spirit to cock a snoot at those detractors still on the shore, lash half a dozen milk bottle containers to the hounds and take every opportunity to refine the sailing systems and his technique. Had I got as far I would certainly would take that approach for now.


Well said.
Over the nearly ten years or so since I started playing with what became the Alto (wasn't planned), I have been amused rather than put off by the many doubters with their suspect comment. 'Swinging the pole not necessary because asymmetrics only use apparent wind', and so swinging pole unnecessary! Interesting that all boats sold except one into BCYC,are into estuaries or, as Graeme, on the sea where there are these strange things called currents, or do I mean 'apparent currents' Perhaps it is the apparent currents which make the swinging pole so desirable. As for non-doubled bottomed boats, 'apparently' they went out with the Titanic or do I mean  the Ark. They are dangerous since they won't turn turtle.
Two new boats have sold since the Boat Show into an estuary that has as well as apparent wind and apparent currents, a phenomena known as 'apparent waves'. Clearly the new owners realised they needed a non 'Garda Class' that can handle such dangerous conditions. 
Since the Dinghy Show two new AltOs have sold and like all other  AltOs, to be sailed, yes in waves! Oh dear and it only has a single bottom. 
thefastexcitingrunningasymmetric
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Post Options Post Options   Quote G.R.F. Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 3:29pm
Originally posted by Do Different

As GRF has seen the performance he hoped for albeit briefly. I would expect a man of his independent spirit to cock a snoot at those detractors still on the shore, lash half a dozen of them to the hounds and take every opportunity to refine the sailing systems and his technique. 

FTFY
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Post Options Post Options   Quote rogue Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 2:23pm
Hi Oldarn, yes I meant more powerful in terms of inverted stability/non-compliance as opposed to raw power from a sailing perspective.

That's a lot of boat to manhandle... 

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Post Options Post Options   Quote Do Different Quote  Post ReplyReply Direct Link To This Post Posted: 26 Apr 12 at 2:14pm
As GRF has seen the performance he hoped for albeit briefly. I would expect a man of his independent spirit to cock a snoot at those detractors still on the shore, lash half a dozen milk bottle containers to the hounds and take every opportunity to refine the sailing systems and his technique. Had I got as far I would certainly would take that approach for now.

Complicated righting systems are a distraction from an inherent design problem as it stands. Surely with some careful consideration of the cross section the volume of the form can be reduced in the right places  to allow it to float lower. This would reduce the inclination to invert in the first instance and allow it ROTATE around it's biggest volume when attempting to right it. Unless a fair percentage of the hull sinks only extreme amounts of leverage will ever lift the opposite side clear of the water. Ref. Oldarn, 505s have big side tanks, the Alto doesn't.   
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