Dart 15 Forums

Look guys.
Here are the new RYA PY numbers for 2011.
It looks like the Sprint 15 Sport is now PY 886 (+3) and the standard mode is unchanged at PY917.
I see that the Dart 18 has also increased from 798 t0 800.
Cheers
Bob


http://www.rya.org.uk/SiteCollectionDoc ... 20List.pdf

PS These numbers are OK when you compare Cats to Cats but hopeless when you compare Cats to monohulls

I have been looking at the RYA system for comparing PYs. In light winds (when cats do poorly) the results are discarded as non valid because they are so bad. This measure is put in to stop badly sailed boats (late starters, capsizes, etc) from distorting the results. The trouble is that even well sailed cats results are discarded in light winds. In stronger winds cats do better and the results are judged valid. The bottom line is that the system tends towards developing unfavourable PYs because our bad days are not used.

This paragraph explains what happens.

"The spreadsheet gets rid of the poor performers. If we take the first race of the TT for example, 44 finishers. It works out an average CT for the top 2/3rds of the fleet and then adds 5%. Boats inside this time are only included, leaving 21 results. Then it works out the average CT from the remaining boats from the first calculation to work out the performance".

The trouble is in light winds all cats usually get thrown out by this criteria.

For a fuller explanation and some debate on it (from a monohull perspective) read this thread on the Y&Y forum.


http://www.yachtsandyachting.com/forum/ ... e-py-stats

1 Effect on Travellers
I assume that the current 2010/1 Winter Traveller Series will be completed on the old PYs - ie the same as was announced by the Sprint 15 Class Association for the Series and consistent with the PYs used for the previous events in the Series. There is just the one event left - Grafham 20 March.

Although the forthcoming 2011 Summer Traveller Series has been announced on the old PYs, I assume that common-sense will prevail and that the new PYs will be used. For the future, I thoroughly approve of the Erling's decision (as Event Secretary) to announce Traveller and Nationals dates as far as practicable in advance; but it might be sensible not to include the then current PYs as "certain" in future "early" announcements until the RYA has announced the new ones. This amy involve some extra work for Martin - sorry Martin.

2 Comment on PYs

At Queen Mary (my home club) there are too few cats raced regularly for us to enjoy our own start etc. Cats form part of the Fast Handicap category - currently mainly Flying Fifteens and some others like Blaze, and we share our start with the Slow Handicap boats (which are set up to do a lap less).

The Club periodically analyses the results, using the same sort of approach as the RYA PY approach, but I think adopts some more pragmatic rationale. Whatever, as a result the Club de-rates Cats by 5%, by increasing RYA Standard PYs for cats by 5%; note that this means the ratio of QM adjusted PYs for cats remains the same as for standard PYs, so it doesn't affect the differential on the PY system between Cat Classes. Given that Gordon and I provide the bulk of the cat results, this doesn't reflect an abysmal standard of cat sailing. It reflects much more the effect of including cat results in light conditions, and these conditions are probably the most common at this Inland reservoir. While this won't include quite so many results for Gordon - who prefers to sail in medium plus breeze - it does include quite a lot of mine because I miss so much sailing because of health/injury problems there are times when I'm going to sail almost regardless of wind strength.

I suspect that it is not just cats poor performance in light wind conditions that means that cats results in those conditions are rarely included in the PY calculations. I suspect that many cat sailors prefer not to sail in light conditions because the sailing is the so far from the "flying a hull" that attracted them to cats in the first instance.

QMSC's premier Series is the Summer Wednesday Evening Series - the only Series at QMSC in which all Classes of boat can enter (There are separate Series for 3 Laser Classes, 2 Classes that sail Windward/Leeward and a Windward/Leeward Handicap Class). Last year I had to miss quite a few evenings, but I was keen to do the minimum number of events to rank (to avoid being saddled with Total no of entrants plus one in one or more results). As a result I had 3 wins, 1 second, 2 at 3rd last, 1 at 2nd last with just 2 "in the middle". Success was substantially correlated with wind strength, with a little benefit/disadvantage from the course used on the night (QMSC uses a rotation of courses so as to minimise favouring of classes of boats). Had standard PYs been used I would still have had 2 wins - one win being relegated to a 2nd.The helm who won last year's Wednesday Evening Series had a hatful of wins (just like the previous year!); when the wind is up, he tends to tell me something like "your rocketship was was working ok tonight".

It would seem sensible for the RYA to consider a less simple approach when calculating PYs - excluding results for a boat/crew not on the basis of just the one race but on the basis of "aggregate boat/crew Club performance" being in the range that the RYA include for any one race. This would mean that boats that performed relatively poorly in some conditions would be more sensibly handicapped. But it would mean more work for the people at the Clubs who collate their Club results for the RYA? There are few enough clubs who contribute results to the PY scheme, and one doesn't want to discourage any who do. But the notion that the handicaps would be fairer might well be a significant reason for them to continue, and maybe for other clubs to start or restart contributing.

It would seem sensible for the RYA to consider a less simple approach when calculating PYs - excluding results for a boat/crew not on the basis of just the one race but on the basis of "aggregate boat/crew Club performance" being in the range that the RYA include for any one race. This would mean that boats that performed relatively poorly in some conditions would be more sensibly handicapped

That would be so simple to implement.

I propose this system where v in wind speed in knots, m is the moon phase in seconds from the new moon, p = Portsmouth Yardstick, s = height of waves in rods, w = periodicity of waves in nano-seconds, f = weight of crew in ounces, L = 1 if leap year, else=2, H = new handicap.


H = ∏*((p/s*w)/(134/m)^2)^(w/f)+√(v*L)

Simples.

Liam wrote:

H = ∏*((p/s*w)/(134/m)^2)^(w/f)+√(v*L)

I like the simplicity, and so straightforward too.

Robert wrote:

H = ∏*((p/s*w)/(134/m)^2)^(w/f)+√(v*L)

For the educated and inebriated, I once heard a limerick as follows

The was a professor from Trinity Hall
Who had a mathematical crystal ball.
The square of its weight
Plus his tool minus eight
Equals PY and sweet f*** all!

Andrew Hannah wrote:

Robert wrote:

H = ∏*((p/s*w)/(134/m)^2)^(w/f)+√(v*L)

For the educated and inebriated, I once heard a limerick as follows

The was a professor from Trinity Hall
Who had a mathematical crystal ball.
The square of its weight
Plus his tool minus eight
Equals PY and sweet f*** all!

I'm very flattered, Sir, but methinks thou shouldst but quoting Liam - not I