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  #1  
Old 07-31-2011, 07:20 AM
caiman caiman is offline
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Handicap/PY number

Can anyone please tell me the formula(if there is one) for working out the relative 'handicap' numbers,so that I can race my tri against the local monos on an equal footing?Also,can anyone point me to how I work out a PY number?Alternativly,can anyone point me towards a table of the relative performance numbers for 'production' tris so I can get a 'ball park' comparrison.
I was awarded 'victory' in a race yesterday where the results where obviously and undoubtably in my favour,but it would be nice to have a 'precise' figure.
Cheers
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Old 07-31-2011, 07:50 PM
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Richard Woods Richard Woods is offline
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It is very difficult to get monos and multis to race fairly on handicap

Having said that i suggest you contact some one at MOCRA or Simon Forbes at ISAF

If you search on line for Texel Rating/yardstick you should get a list of most multhulls with their dimensions. (Some of the sites will be in Dutch)

Richard Woods of Woods Designs

www.sailingcatamarans.com
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  #3  
Old 08-06-2011, 02:51 AM
Samnz Samnz is offline
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Quote:
Originally Posted by caiman View Post
Can anyone please tell me the formula(if there is one) for working out the relative 'handicap' numbers,so that I can race my tri against the local monos on an equal footing?Also,can anyone point me to how I work out a PY number?Alternativly,can anyone point me towards a table of the relative performance numbers for 'production' tris so I can get a 'ball park' comparrison.
I was awarded 'victory' in a race yesterday where the results where obviously and undoubtably in my favour,but it would be nice to have a 'precise' figure.
Cheers
over here they just handicap us so high we cant win. then when we win the forget to mention us, or give us a "first multihull" prize (even if there is no other multihulls) thats why I dont race in the mixed fleets, just stick to the multihull divisions....
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Old 08-06-2011, 07:56 AM
caiman caiman is offline
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I understand your words.'We British' dropped 'Cats' out of the Olympics !!! There seems to be a worldwide reluctance for the 'Monos'to accept the 'Multies'.However,on the day in question,Caiman finished 5 hours ahead of the second boat,a Moody 31.In all fairness to the Race Officer,he worked out the finish time differences.Using the Moody's time,(or applying my time to the Moody)my handicap would have worked out to be '500'(whatever that means).In my opinion,the reason for the vast difference,was due to Caiman using a different 'route' to the 'mark',and also the wind dropping,and the tide increasing,when Caiman had crossed the line.
Unfortunatly,there are few Multies localy,an old Telstar,an old Heavenly Twins,and a 42 foot Cat which I cannot remember what 'Class' it is.None of these 'race'.The local (very small)racing fleet are all cruising Monos.
Having come into Multihull sailing from racing motor cycles at Club level for ten odd years,I miss the 'competition' side of things.
Thank you all for your continued help.
Cheers
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  #5  
Old 08-07-2011, 08:47 AM
rapscallion rapscallion is offline
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there is a nice equation in the book, multihulls for cruising and racing...

I believe it's called an MR number, or measured rating =2((SA*WL)/D)^(1/2)

where SA = Sail area in sq meters (as measured for bruce number)
WL = waterline length in meters
D = displacement in kg
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Old 08-07-2011, 08:49 AM
rapscallion rapscallion is offline
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there are PHRF and portsmith ratings for monos and multis.. I would start there in an internet search
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