Historical Information on PY Numbers for IC

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Colin Newman
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Joined: Sun Sep 07, 2003 9:46 pm
Location: United Kingdom

Historical Information on PY Numbers for IC

Post by Colin Newman » Wed Jun 18, 2014 11:14 am

Changes to the PY Number for the International Canoe Over the Past Thirty Years

For all development classes, the RYA has adopted the policy of giving all boats in the class a PY Number based on the latest design evolution of the boat. Thus in the list of published PY Numbers for the International Canoe, the 2014 PY Number for the class is listed as 895 for the non-spinnaker International Canoe. Whilst this number is appropriate for the 2009 Rules boats, it is not a fair Number for the earlier Nethercott hull ICs which are 33.5 Kg heavier and wider in the hull than the 2009 Rules boats. Until recently, the published PY Number for the Nethercott ICs was 905, but they are now no longer listed by the RYA. However, the guidance from the RYA remains that for 'development classes where the Portsmouth Number is likely to vary depending on the age and design of the boats, clubs should consider adjusting the Number where it does not reflect the performance of a particular boat (excluding Crew Skill Factor)'.

At this years Nationals there was some discussion about what guidance the class can provide for the owners of older ICs who need to negotiate an appropriate, fair PY Number with their home club relating to the particular older IC they are racing at their club. It could be argued that boats should be raced off the PY Number that was in force during the year in which the particular older IC was built. As it happens I have kept copies of most past PY lists, hence I volunteered to publish on the class web Forum the historical PY numbers for the IC over the past thirty years. I bought my first IC in September 1987 (K126). Up to 1995 PY Numbers were based on a three number basis with no easy way of converting old PY Numbers into the post-1995 system based on 1000. The historical data is as follows:

Year PY Number
1985 101
1986 100
1987 99
1988 99
1990 98
1991 97
1992 97
1993 97
1994 97
1995 97

1996 919
1997 915
1998 914
1999 911
2000 911
2001 909
2002 909
2003 908
2004 908
2005 905
2006 and from then on up to 2013 the PY Number for the Nethercott hull IC remained at 905. In terms of IC development my own Nethercott IC, 'Extended Play', GBR 295 which was built in 2003 was almost the last IC built in the UK not to have a spinnaker. From 2003 onwards, almost all new boats and IC development was focused on the Asymmetric Canoe until the advent of the Development Canoe which then became the 2009 rules IC, hence it is not surprising that the IC PY stayed at 905 for the Nethercott hull, non-spinnaker boats.

It was not until 2003 that the RYA first published a PY Number for the AC as 868 accompanied with the designation 'more returns required'. From then on AC Numbers changed as follows:

Year PY Number
2003 868
2004 872
2005 873
2006 873
2007 873
2008 873
2009 870
2010 870
2011 870
2012 870
2013 870
2014 870

I hope these figures help the owners of older ICs to negotiate fair PY Numbers for their boats and that others in the class agree that having the odd member of the fleet with an obsessional side to his character, yours truly, has some advantages!

Colin Newman

chrishampe
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Re: Historical Information on PY Numbers for IC

Post by chrishampe » Wed Jun 18, 2014 3:25 pm

The old 2 digit py numbers can be converted to 3 digit equivalents by multiplying them by 9.5.

Thus:

1985 - 960
1986 - 950
1987/88 - 941
1990 - 933
1991/95 - 922
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jimc
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Re: Historical Information on PY Numbers for IC

Post by jimc » Thu Jun 19, 2014 11:21 am

Disclaimer: I am on the RYA Portsmouth Yardstick Advisory group, but as an interested party I don't take part in any decisions related to the IC handicap. Opinions expressed are strictly personal, not those of the RYA or the PYAG .
Colin Newman wrote:For all development classes, the RYA has adopted the policy of giving all boats in the class a PY Number based on the latest design evolution of the boat.
I'm afraid I shall have to dispute that Colin. The PY number is based on the observed performance of the active boats out there in the clubs - or at least the clubs that participate in the scheme by filling in returns. Its in the middle of changing fairly radically now that there's a web based system where the RYA actually receive race results directly.
In the paper return system the number proposed is based on the opinion of the club handicappers, hopefully assisted by various tools which the RYA provides to help them estimate numbers. The club was encouraged to adjust the number according to the perceived skill of their various fleets, but the RYA tools produce a number that reflects the average of about the top 75% of results.
In the web system entire race results are uploaded to the PY web site, and numbers are calculated from there. The influence of the club handicaps is considerably reduced. The actual calculation method is complicated, but the end result is again a number that reflects the average of about the top 75% of results.

In practice this year's published number reflects a fleet that is, according to my best estimates looking at the clubs involved, about 75% Nethercott, 25% newer boats. If we wish clubs to separate the Nethercotts and the new boats in their returns we'll have to make it a great deal easier for them than it is now. Some have enough trouble distinguishing IC from AC!
chrishampe wrote:The old 2 digit py numbers can be converted to 3 digit equivalents by multiplying them by 9.5.
Its not quite 9.5... 9.47 is closer although the difference is minimal.

This is the data I have, converted to modern equivalents, which you can regard as semi official as its been compiled mainly from RYA records. As you will see there's a big hole from mid 60s to the 80s. Note of course that there was lower granularity in the early days : 1 point then was something like 12 points now. You have to be careful with old numbers, especially the very old ones. Although the actual base point of the PY hasn't drifted significantly relative to the UK sailing fleet as a whole, all classes have got faster with improvements in materials, some faster than others, and changes in sailing technique are also significant. I'm pretty confident that if you brought the 1974 Laser world champion and boat through a time machine and had them race against the 2014 Champion it would be a very one sided race, and its even more so with boats like Solos, Fireballs and the like. Some "restricted" classes haven't actually progressed in performance any more than similar one designs! I have a theory that something in the combination of laminate sails, carbon masts and foam sandwich hulls is responsible for a major jump in the performance of certain classes, but trying to put some meat on the theory is difficult and I haven't succeeded yet. I *suggest* though that if your old boat has been upgraded with a plastic mast and mylar sails you should not be claiming a handicap based on its performance when new with cloth sails and tin mast.

IC
1960 904*
1961 904*
1964 862
2014 895
*terylene sails, using a contemporary conversion factor from the published number for cotton sails

IC OD
1981 927
1982 927
1983 927
1984 955
1985 955
1986 946
1987 936
1988 936
1989 927
1990 927
1991 917
1992 917
1993 917
1994 917
1995 917
1996 919
1997 915
1998 914
1999 911
2000 911
2001 909
2002 909
2003 908
2004 908
2005 905
2006 905
2007 905
2008 905
2009 905
2010 905
2011 905
2012 905
2013 905

IC AC
2003 868
2004 872
2005 873
2006 873
2007 873
2008 873
2009 873
2010 870
2011 870
2012 870
2013 870
2014 870

*Personally* I don't think that 895 is any fairer for a new boat than it is for an old one. I can only repeat my opinion from an earlier thread:

"My personal opinion, for what ever that is worth, is that the new boats should probably be on 875 or 880, and the one designs should be on 905, but inland clubs, especially the smaller ones, might find that 905 is very hard to sail an OD to without a regular sea breeze, and depending on their conditions they might like to move it out, maybe to 920 or 925 for middle sized lakes."

Del Olsen
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Joined: Tue Feb 24, 2009 2:50 am

Re: Historical Information on PY Numbers for IC

Post by Del Olsen » Sun Jun 22, 2014 5:23 pm

Thanks for the info, great Stuff. I've wondered for a long time if there was a conversion factor to convert current UK numbers to something closer to what USSailing uses.
Not that they are all that current, they haven't changed the I-14 number in over 25 years!
In the time I've sailed an IC the Dpn has gone from 83 in 1981 to 79.1 the last time it was reduced about 12 years ago when the ODs were at the highest state of development.

I do he handicapping on a 14 mi pursuit race RYC hosts in the Spring and it will be helpful when an RS 800 or some other rare bird shows up to give it a reasonable rating.
BTW I've reduced the New Rules IC rating to 77 for the race and we had 4 of the top 5 this year in a race that started over at the 2nd mark with everyone in a clump. We were 1-2 in the 2013 event, so looks like we need another reduction or we will be accused of favoritism and no one will want to come and play!
Del

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