Laser 161752 Tynemouth |
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Laser 140101 Tynemouth |
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Laser 28 - Excellent example of this great design Hamble le rice |
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List classes of boat for sale |
New class PY numbers? |
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PeterG ![]() Really should get out more ![]() Joined: 12 Jan 08 Location: United Kingdom Online Status: Offline Posts: 822 |
![]() ![]() ![]() ![]() Posted: 17 Feb 17 at 5:09pm |
Or you could fashion a formula based on boat length, weight, sail size, displacement, etc
My initial response to that is that it would not be a bad way to generate initial PYs, that could then be updated in the usual way. However, the danger with that approach is that designers of new boats could end up designing to handicap, in the way IOR boats were (and no doubt others still are). That would tend to push new designs into a limited range of hull shapes etc. And I'd hope we would all agree that those sort of rule based distortions are best avoided if designers are going to concentrate on designing the "best" boat for whatever niche they are targeting.
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Peter
Ex Cont 707 Ex Laser 189635 DY 59 |
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Sam.Spoons ![]() Really should get out more ![]() Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3401 |
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I started the thread out of curiosity, the Spice is simply my own reference point. I know there is no possibility of there ever being a 'proper' handicap for it, (see above) and I'm perfectly happy for their to be no further mention of it in this thread. But, how handicaps are arrived at is something that interests me and rather than take the H2 thread even further off topic I decided to start this one (not that it helped mind you). I understand how PY numbers for established classes are calculated, I'm sometimes surprised at where the numbers end up. Musing over the factors that affect them seems a reasonable way to spend a quiet afternoon.
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iGRF ![]() Really should get out more ![]() ![]() Joined: 07 Mar 11 Location: Hythe Online Status: Offline Posts: 6499 |
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Well that depends on the formula, but better i would have thought than the current scenario where old designs get given a makeover, in light stiff construction and marketed as racing Bandits. Wayfarer being the current example. |
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Sam.Spoons ![]() Really should get out more ![]() Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3401 |
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Wasn't weight as it affects PN discussed on here recently? If GRFs formula would stifle dinghy development (which I agree it probably would) it should still be possible to create a formula which gave a reasonable correction factor for changes in hull/sailing weight, increased sail area and other changes to an established class. Sailing a two hander solo, with or without trapeze and/or kite should also be fairly easy to cater for. Of course things like a new hull shape in a development class couldn't be so easily guessed at but I guess that is built into the PN for those boats.
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davidyacht ![]() Really should get out more ![]() Joined: 29 Mar 05 Online Status: Offline Posts: 1345 |
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I would have thought that a formula could give a reasonable stab at an old style 2/3 digit PY number, even for different development class shapes, since the differences in designs are in seconds rather than minutes.
Some kind of rise of floor or prismatic coefficient factor could deal with skinny unstable but fast boats c/w boats of similar dimensions but fatter and more stable. Would the formula be secret like IRC? Which would leave room for the conspiracy theorists to suggest that builder's are in cahoots with the handicappers. What any handicap formula would not deal with unless the RO had some subjective input, is the relative performances of different types of boat in different conditions and varying wind conditions; i.e. Some classes excel on beat and running courses, others in light winds, others when it is blowing dogs off chains. Ultimately people might conclude that pulling numbers out of a hat in a committee room might work better. |
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Happily living in the past
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Sam.Spoons ![]() Really should get out more ![]() Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3401 |
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Just a thought, if designers knew that the numbers would be adjusted to represent the 'real world' performance of the boat within a couple of years would that not remove the incentive to design to the rule?
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Rupert ![]() Really should get out more ![]() Joined: 11 Aug 04 Location: Whitefriars sc Online Status: Offline Posts: 8956 |
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2 years of making hay while the numbers are kind? I can see a builder taking that, and hoping there are enough for one design racing at the end of it. If there aren't, then cut loses and bring out another one.
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Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686
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KazRob ![]() Far too distracted from work ![]() ![]() Joined: 22 Oct 16 Location: Scotland Online Status: Offline Posts: 245 |
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It's worth reading "Yacht Rating" if you can get a copy (https://www.amazon.co.uk/Yacht-Rating-Success-Failure-Competitors/dp/0952947803) to see the futility of trying to predict sailing boat performance by a rule, how the law of unintended consequences seems to arise every time and mostly the fact that it's all been tried before.
If it works "well enough" that's probably the best you can hope for
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iGRF ![]() Really should get out more ![]() ![]() Joined: 07 Mar 11 Location: Hythe Online Status: Offline Posts: 6499 |
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The thing is, it's basic physics that defines a boat performance and it is quantifiable, What isn't necessarily quantifiable is the variable performance across wind strengths, but then like now, that's the same for everyone.
What is wrong with the current system is for the sake of argument lets call it indifference, and the focus on a few particular classes and the others get to go hang. I believe that the boat 'Performance Quotient' for sake of a better term should be fixed once defined and only altered if there are physical changes. Sailors change, they have good days, bad days, make mistakes, the weather has windy years, calm years, there are shifts in volumes of performance types, there are any number of 'chaos' factors that get applied to the current system, which fair enough if that style of handicapping is what's preferred all well and good, but out of the gate the boats themselves should be compared like for like first as a point of reference.. A boat with a given length, volume, a particular sail size with a particular crew weight will perform to a particular speed compared with another with different statistics, big sails go faster than small sails, big volume boats support more crew weight than low volume boats these factors are particularly apparent on fresh water and so they are quantifiable. If you really go into it hull types rounded v flat planing etc can all be formulated if there were the desire for it. But all the time the luddites are happy to tolerate the status quo then it's not going to happen really is it? Edited by iGRF - 18 Feb 17 at 11:35am |
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Dougaldog ![]() Far too distracted from work ![]() Joined: 05 Nov 10 Location: hamble Online Status: Offline Posts: 356 |
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Again, I think Graeme has 'fingered' one of the problems facing any builder thinking of launching either an all new boat or a fettled version of an old classic. Where I don't agree is in his solution (if he'll excuse the pun). With modern tracking devices it should be an easy matter to have a 'sailor boy stig' ( or a whole school of SB Stigs) - so as to match boat and a range of crew weights and sail it over a pre determined course and then compare the results with a known factor. And yes, that could well be the L*ser as in theory the boat itself will not change. I know that the people at Sail Racer were quite happy to do some demos on this (and that may still happen). Then, when Mike at 'Circus' (name changed to avoid conflict with that well know sailing club seen at the winter events) launches his next new single hander project
a day/weekend spent with the people from Sail Racer could well spit out a number that is an honest and defendable trial number. I can only see one problem! You'd have meaningful data on a few boats - but that then questions the rest of the sh*t numbers that are out there! Could be - should be - done! D
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Dougal H
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