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Post Options Post Options   Quote transient Quote  Post ReplyReply Direct Link To This Post Topic: New class PY numbers?
    Posted: 18 Feb 17 at 2:06pm
Originally posted by iGRF


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?



The biggest issue with the current system IMO is the lack of provision for sailing conditions: Tide, waves, gusts etc. These factors have much more impact than the ones you're proposing to sort out. 

I can't see how your system would iron these things out. The relevant factors are way too complicated.
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Post Options Post Options   Quote iGRF Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 3:54pm
Originally posted by Dougaldog

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).


Even better, I'd be more than happy with that sort of scenario, as I think would any prospective builder, especially if there were some sort of boat proving centre where you simply took your boat to have it ratified and it's PQ issued.

So, the obvious question is how does something like this get financed, and the only method short of trade sponsorship would be subscription. So, subscription to what? To the Handicap Racing Class or Federation of Classes, and that puts you directly in potential conflict with you know who, not that there's a damn thing they could do about it, lets face it they've f**ked about long enough and delivered nothing.
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Post Options Post Options   Quote Sam.Spoons Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 4:19pm
Originally posted by transient

The biggest issue with the current system IMO is the lack of provision for sailing conditions: Tide, waves, gusts etc. These factors have much more impact than the ones you're proposing to sort out. 

I can't see how your system would iron these things out. The relevant factors are way too complicated.

I doubt any system could do that and I doubt race officers/race committees would want to have the extra complication of deciding if it was a windy/moderate/lightwind race, and it probably changed during the race. However a simple means of applying a handicap to a new class has it's attractions even though it's not going to be the most accurate (so err on the low side until results suggest otherwise). Also a simple method of re-rating two handers when sailed solo, without a spinnaker and/or trapeze(s) may find favour and encourage the owners of 'unsuitable' boats to continue racing them when the crew grows up and goes to uni......


Edited by Sam.Spoons - 18 Feb 17 at 4:20pm
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Post Options Post Options   Quote Dougaldog Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 4:48pm
iGRF and others. Something along these lines  - at least, in terms of a demo, could still happen. I was having lunch out the other day (and I remembered my wallet - that makes it an important event) and this was being discussed. I was happy to contribute - as an 'honest' tester and scribe but this just highlights the next problem; where would you post the results? This was the sort of thing I could do back in the days of Dinghy Mag but today....I just don't see the outlet for this sort of writing.
But it is a bit like the FOM. You need a venue, some boats, rib for photos, SailRacer to do the techy bits. I've some ideas.....one of the advantages of being an independent is that I have some freedom to think outside the constraints of advertising budgets and the like. Will you be at the Dinghy Show? if so, track me down and I'll give you the insider story!

D
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Post Options Post Options   Quote transient Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 5:35pm
Originally posted by Sam.Spoons

Originally posted by transient

The biggest issue with the current system IMO is the lack of provision for sailing conditions: Tide, waves, gusts etc. These factors have much more impact than the ones you're proposing to sort out. 

I can't see how your system would iron these things out. The relevant factors are way too complicated.

I doubt any system could do that and I doubt race officers/race committees would want to have the extra complication of deciding if it was a windy/moderate/lightwind race, and it probably changed during the race. However a simple means of applying a handicap to a new class has it's attractions even though it's not going to be the most accurate (so err on the low side until results suggest otherwise). Also a simple method of re-rating two handers when sailed solo, without a spinnaker and/or trapeze(s) may find favour and encourage the owners of 'unsuitable' boats to continue racing them when the crew grows up and goes to uni......


My point exactly.

These factors have massive effect on relative performance, a much bigger effect than the complaints GRF has highlighted. A 2k for example might be a dog on a pond but put it on the open sea and it becomes a killer.

A bit like complaining that a car has a puncture when in actual fact the engine has fallen out.

It doesn't and can't address the real, major issues.


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Post Options Post Options   Quote RS400atC Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 6:33pm
Originally posted by transient

....

These factors have massive effect on relative performance, a much bigger effect than the complaints GRF has highlighted. A 2k for example might be a dog on a pond but put it on the open sea and it becomes a killer.

A bit like complaining that a car has a puncture when in actual fact the engine has fallen out.

It doesn't and can't address the real, major issues.


2k looks pretty dog-like on the sea most of the time.
But there is a point there, that asy boats like the 2k don't work on PY against Ents or Merlins or GP14s, because the boats are disparate.
Likewise racing the 400 against say Scorpions, we will lap them if the wind and course suit us, other days we can't shake them off.
An RS400 on a triangle course where our kite is just right needs a different PY from on a square course where we can't carry the kite on the reaches and have to do 40% extra distance on the run.
If people stopped trying to use PY outside the bounds where it can work, the numbers might have a chance of making sense.

To get back to th OP, most new classes are comparable to several existing classes. If you come up with a 2 person hiking boat, about 14 ft long, sym kite I'd look at the weight, sail area, sophisticated rig or not, then have a guess at where it slots in between a Merlin and a GP14. Or maybe Skipper 14 to Bosun spectrum?
Likewise if you are talking one man, one sail, just look at all the others of the same concept and similar size.

If you want to pluck a PY for the spice out of thin air, don't look at catamarans, toppers or Merlins.
Look at the int 14 and see how many excuses it's got to be slower. Look at the L4k and the 3k. Maybe the B14. Don't look at things with grossly diffferent length, weight, righting power or sail area, Don't even think about thinking about boats with different basic rig concept.

But at the end of the day, there are still going to be boats which don't deliver what their outline spec suggests they should.
Just as there have been designs of Merlin which never went anywhere, there have been many boats which are simply not very fast despite lots of righting power and sail area, even if you make allowance for things like beam at the waterline which makes a sensible boat for beginners.
Then you've got to allow for class rules which restrict performance, like some of the nastier SMOD sails or limitations on sheeeting angles etc. Or maybe the other extreme of boats with raking rigs etc.
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Post Options Post Options   Quote Rupert Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 6:42pm
For the Spice, all you have to do is decide how much difference a bigger rig and extra wire makes over the Buzz. Can't be more than 30 or 40 points, can it? Still the same flat, tea tray hull, same length, similar weight.
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Post Options Post Options   Quote transient Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 6:52pm
Originally posted by RS400atC

2k looks pretty dog-like on the sea most of the time.

Chortle, seperate discussion needed there about differing hull weights within a class (except that it's already been discussed to death).


But there is a point there, that asy boats like the 2k don't work on PY against Ents or Merlins or GP14s, because the boats are disparate.
Likewise racing the 400 against say Scorpions, we will lap them if the wind and course suit us, other days we can't shake them off.
An RS400 on a triangle course where our kite is just right needs a different PY from on a square course where we can't carry the kite on the reaches and have to do 40% extra distance on the run.
If people stopped trying to use PY outside the bounds where it can work, the numbers might have a chance of making sense.

yep. triangular courses where an assy can fly a kite for 66% + of the course and a symm for sometimes 0%




Edited by transient - 18 Feb 17 at 6:52pm
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Post Options Post Options   Quote Sam.Spoons Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 6:53pm
Originally posted by RS400atC

To get back to th OP, most new classes are comparable to several existing classes. If you come up with a 2 person hiking boat, about 14 ft long, sym kite I'd look at the weight, sail area, sophisticated rig or not, then have a guess at where it slots in between a Merlin and a GP14. Or maybe Skipper 14 to Bosun spectrum?
Likewise if you are talking one man, one sail, just look at all the others of the same concept and similar size.

If you want to pluck a PY for the spice out of thin air, don't look at catamarans, toppers or Merlins.
Look at the int 14 and see how many excuses it's got to be slower. Look at the L4k and the 3k. Maybe the B14. Don't look at things with grossly diffferent length, weight, righting power or sail area, Don't even think about thinking about boats with different basic rig concept.

But at the end of the day, there are still going to be boats which don't deliver what their outline spec suggests they should.
Just as there have been designs of Merlin which never went anywhere, there have been many boats which are simply not very fast despite lots of righting power and sail area, even if you make allowance for things like beam at the waterline which makes a sensible boat for beginners.
Then you've got to allow for class rules which restrict performance, like some of the nastier SMOD sails or limitations on sheeeting angles etc. Or maybe the other extreme of boats with raking rigs etc.

A good post RS, thanks. That seems the most sensible way (and I assume that's how it's done) but no one person/committee makes the decision. In some cases I guess it's the designer, others the manufacturer/marketing guys and yet others the hosting clubs racing manager. Those with axes to grind will recommend a number that makes the boat either seem faster or one that makes it more competitive depending on the boat and their aspirations for it. 

I do like GRFs suggestion that there should be a 'scratch' boat that remains on 1000 while the others move around it, that way all those lost classes that haven't had a real PN for years will, in theory, have a fixed reference point but even the L@ser will have got a little faster over the years, particularly with the Mk2 sail and new carbon topmast so even that is doomed to failure Unhappy
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Post Options Post Options   Quote Dougaldog Quote  Post ReplyReply Direct Link To This Post Posted: 18 Feb 17 at 6:58pm
Good point Rupert. But in a way - that is just what I'm saying. If you had an accepted number for the Buzz (based on real data) and then you wanted to launch the Spice, you ran it over the pre determined course for a day or so, downloaded the tracking data, compared it to the and then you can make an informed decision. Rather than the wet finger in the wind, is it 30 points or 40 (or 20 or 50 even) you've data, fully in the public domain, that everyone can see.
RS 400 also makes a good point. You're going to have to compare apples with apples. It isn't difficult to set a bench mark for a genre, all the more so when it is a SMOD, a boat that once it has an established number, it is hard to explain why the PY is changing (unless there has been a change in the equipment used). In the end - it isn't rocket science  - but what would we have to complain about then. I'm sure the man of kent will come up with something!

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