I am very aware that F18 PHRF is a topic that has been talked around in circles, but I'm in a situation where I may legitimately need a rating for my F18 Tiger. I've been talking with Grand River Sailing Club (Grand Haven, MI) my local Wednesday night sailing group about racing with them. They are open to the idea of me racing with them. I would like to find a fair way to rate my boat so I can improve as a sailor by being able to look at reasonable metrics, but I also want to do my due diligence so I don't get into an Amaryllis situation.

The next closest cat club is Hobie Fleet 519. They are an hour and a half drive and don't have any place for me to keep my tiger. Not that I would want to leave it there as I also race CRAM on the weekends.

When talking to them the only thing they really asked of me was to get my boat PHRF rated, but I had to explain that that doesn't exist for multihulls. I told the person I was working with about GLMRA ratings and how the numbers used are similar to PHRF, but I don't know accurate it is to race PHRF numbers against GLMRA numbers straight up.

Question 1: Does anyone have any experience using a GLMRA number against PHRF numbers?

The other option is a conversion from Portsmouth, SCHRS, etc.. I know there are conversion formulas out there yet I can't seem to find them easily. Between what I have see people post about a hypothetical F18 PHRF, whether it be opinion or conversion, I have seen it range from -40 to +40. I also understand that there are limitations on converting between Time on Time and Time on Distance rating systems. Either way the consensus seems to be that most numbers which may be used for an F18, or any other catamaran for that matter, the catamaran will get killed in light air, but the monohulls won't even have a snowflake's chance in hell in moderate to heavy air against me.

Question 2: Are there any conversions from existing rating systems to PHRF which factor in wind speed?

I feel that if I was able to use a PHRF rating that factored in windspeed (I know it normally doesn't) I might have the best chance in coming up with some fair rating numbers.

Thanks in advance.

I posted this on /r/sailing and got an answer to my 'Question 2'

Using the DPN to PHRF conversion and accounting for wind speeds my PHRF would look something like this

base value: 44.4
0-3 knots: 62.4
4-10 knots: 53.4
11-16 knots: 37.8
17 + knots: 27

I guess I'm still curious if anyone has had experience with racing GLMRA ratings against PHRF ratings, and what would a GLMRA rating be for an F18.

tiberiusgv,

I will point you to our website: https://sites.google.com/view/communityfleet. We have been at rating mixed fleets for about 15 yrs. Our latest documentation outlines the ratings and formulas that we use very successfully. If you have any questions, feel free to contact me directly.

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dk

Blade F-16
Hobie 14
Corsair F-242
Mirage 25 (Sold)
Hobie Tiger (Sold)
Hobie Tiger (Sold)
TomCat 6.2 (Sold)
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The conversions from DPN to PHRF works for like boats because relative speed stays somewhat consistent as the wind increases. At least within the changes to the applicable ratings. That isn't necessarily true if you are racing multi v mono as the relative speed variation increases for nearly every boat you will race against. That is why we use, successfully I may add, B Factor adjustments according to wind conditions.

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dk

Blade F-16
Hobie 14
Corsair F-242
Mirage 25 (Sold)
Hobie Tiger (Sold)
Hobie Tiger (Sold)
TomCat 6.2 (Sold)
--