New Posts New Posts RSS Feed: PY Inland vs Sea
  FAQ FAQ  Forum Search   Register Register  Login Login

PY Inland vs Sea

 Post Reply Post Reply Page  <1 910111213 16>
Author
JimC View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 17 May 04
Location: United Kingdom
Online Status: Offline
Posts: 6662
Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Topic: PY Inland vs Sea
    Posted: 22 Oct 14 at 9:58am
Not hard to crudely classify venues, a lot harder to do it meaningfully. For example if you think you've got it bad with tide in Chichester harbour, try the current on the River Thames at Thames Sailing club at Surbiton, where you need a fast enough boat to get through the current and a sufficiently manoeuvrable one to be able to keep out of the worst of it.
Back to Top
davidyacht View Drop Down
Really should get out more
Really should get out more


Joined: 29 Mar 05
Online Status: Offline
Posts: 1345
Post Options Post Options   Quote davidyacht Quote  Post ReplyReply Direct Link To This Post Posted: 22 Oct 14 at 11:12am
Originally posted by Steve411

From the Hayling Island website.


Profanity allert!

Seriously, the more you go into this the more complex it gets.

First thought was that in the old days I think you had Primary and Secondary Numbers, PN's were derived from solid data and SN's not.  It was accepted that PN's did not get tweaked and SN's could be.  There were less classes in those days, probably sailed at less clubs, so I guess that the PN's could be trusted more.  

The current hiatus is caused by the explosion of Manufacturers Classes, and the wide variety of types of craft, back then you only had four modes, sit out single hander, sit out two hander, sit out two hander with symetrical spinnaker, two man single trapeze with symetric.  Largely these boats planned in a similar style, and could be accomodated ok on the same course.

The good news is today is that we have the tools to play around with the data using computers, rather than the old tables.  However there does not appear to be sufficient quality or quantity of data for the derived numbers to be reliable (or may be trusted).

It would seem to me, assuming the data crunching could be acheived, that we need an ap or program that allows the race manager to;

Tweak the PY numbers to suit local prejudices, notably what might have been regarded as SN numbers

Apply a wind strength factor
Apply a wind direction factor 
Apply a course factor
Apply a tide factor

This to my mind must be doable, but it would still rely on the judgement of the Manager, so ultimately people would still say they was robbed.



Back to Top
JimC View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 17 May 04
Location: United Kingdom
Online Status: Offline
Posts: 6662
Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Posted: 22 Oct 14 at 11:23am
There were many more classes in the old days you should see the size of the database I have of old Py numbers. Don't forget every little local boatbuilder tried to set up their own classes.

A lot of what you suggest is slowly being developed on the PYS website as time and budget permits, but I think at the moment NHC has a higher priority.
Back to Top
transient View Drop Down
Really should get out more
Really should get out more


Joined: 21 Aug 12
Online Status: Offline
Posts: 715
Post Options Post Options   Quote transient Quote  Post ReplyReply Direct Link To This Post Posted: 22 Oct 14 at 11:41am

Quote David:

"Apply a wind strength factor

Apply a wind direction factor

Apply a course factor

Apply a tide factor"

depends......If you're trying to get a fair result for 1 race then maybe.
If you're working on a series then some of those factors average out, the longer the series the better.

Edited by transient - 22 Oct 14 at 11:43am
Back to Top
Oli View Drop Down
Really should get out more
Really should get out more


Joined: 23 Mar 05
Online Status: Offline
Posts: 1020
Post Options Post Options   Quote Oli Quote  Post ReplyReply Direct Link To This Post Posted: 22 Oct 14 at 1:55pm
what would be truly useful would be for the RYA to state categorically the way they want clubs to adjust and not just give a rough outline of the differing methods available.  That way every club that does adjust is doing so in the same manner. (also helps the sail sec etc as they have nothing to do with it, its the RYA method employed by the club.

Clubs (people) that dont adjust that say their isnt enough data, if you start adjusting (taking transients problem with cadets and toppers a page back) perhaps that'll encourage people to race and then you will have more data to work with.

Courses, you wont please all types of craft all of the time but if you design a set of courses for each wind direction and strength that have equal measures of upwind/downwind/reaching then you've gone along way to giving everyone a fair crack at it.  We have 48 set courses, sometimes theyre perfect and sometimes the wind shifts half way through and a certain class may benefit but on the whole everyone gets a great and fairer sail.

If youre unsure of the system try it in the background for a season or two and post dual results for all to see, but dont tell them which is which (hide the pys) and see which one they prefer by voting.

if you have tow or more handicap fleets arrange more "all in" races so that larger spreads between fleets can be covered, this takes care of tidal factors at the extremes if you do enough of them.  We added a club champions series in which once a month in the second race of that particular day we have an all in start, we also have our trophy all in races and winter / icicle so we now have about 30 all in races a year.
Back to Top
getafix View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 28 Mar 06
Location: United Kingdom
Online Status: Offline
Posts: 2143
Post Options Post Options   Quote getafix Quote  Post ReplyReply Direct Link To This Post Posted: 22 Oct 14 at 10:21pm
Originally posted by davidyacht

 
The good news is today is that we have the tools to play around with the data using computers, rather than the old tables.


I wonder if that's kind of the problem, expectation of the internet user that feedback is easy, change available at the click of a button, why isn't in adjustable, location specific, dynamically adjusted for wind, tide and other conditions.  Yes, the technology probably exists already but I'm not so sure I'd like it to be applied, I find myself hankering for the days of tables and pen, paper and calculator.
Back to Top
Time Lord View Drop Down
Far too distracted from work
Far too distracted from work


Joined: 03 Dec 13
Location: Warwickshire
Online Status: Offline
Posts: 301
Post Options Post Options   Quote Time Lord Quote  Post ReplyReply Direct Link To This Post Posted: 23 Oct 14 at 9:49am
I find myself hankering for the days of tables and pen, paper and calculator.

Surely a slide rule rather than a calculator - at least the battery won't run out!!
Merlin Rocket 3609
Back to Top
Rupert View Drop Down
Really should get out more
Really should get out more


Joined: 11 Aug 04
Location: Whitefriars sc
Online Status: Offline
Posts: 8956
Post Options Post Options   Quote Rupert Quote  Post ReplyReply Direct Link To This Post Posted: 23 Oct 14 at 10:35am
We still use the pen and paper, but the calculator has made the Langstone tables redundant, of course. The results are then put on sailwave back at the sailing sec's house. They usually come out the same!
Firefly 2324, Puffin 229, Minisail 3446 Mirror 70686
Back to Top
kneewrecker View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 09 Apr 14
Online Status: Offline
Posts: 1586
Post Options Post Options   Quote kneewrecker Quote  Post ReplyReply Direct Link To This Post Posted: 23 Oct 14 at 10:42am
Ah yes the human element- someone number crunching in the corner of the bar like days of yore...  that commanded a certain bit more respect than some spreadsheet churning, auto uploading 21st century nonsense.   LOL
Back to Top
transient View Drop Down
Really should get out more
Really should get out more


Joined: 21 Aug 12
Online Status: Offline
Posts: 715
Post Options Post Options   Quote transient Quote  Post ReplyReply Direct Link To This Post Posted: 23 Oct 14 at 1:05pm
struth...

.....when I were a lad.....

Back to Top
 Post Reply Post Reply Page  <1 910111213 16>

Forum Jump Forum Permissions View Drop Down

Bulletin Board Software by Web Wiz Forums® version 9.665y
Copyright ©2001-2010 Web Wiz
Change your personal settings, or read our privacy policy