portsmouth calculations

You multiply the modification factors by the base number (rather than subtract them from the base number).

http://www.ussailing.org/portsmouth/howto.asp

You need to multiply the ratings by the modification factors. Not subtract. Also keep in mind that the rating is intended to grade the potential of the boat without consideration for the sailor. Getting this deep into the modification factors with a modified boat is a grey area when using a handicap system that is established based on performance data.

The HobieSX rating you are suggesting has an antiquated deep-downwind spinnaker, 40 lbs of wings, and only rates .2 different than a standard Hobie 18 without a spinnaker. In my opinion, it's not fair to use the Hobie 18sx rating to run a modern F18 spinnaker on a Hobie 18 without the wings. You should start with the Hobie 18 rating and take a hit for a taller mast, non-class legal mainsail, and spinnaker. The jib is smaller than the standard jib so I wouldn't necessarily start with taking a deduction for that.

Also understand that while you can argue for a particular rating, at the end of the day, the rating and the handicaps applied is ultimately the responsibility of the PRO.

Using DPN numbers (not wind correctors)
Hobie 18 = 71.4
Spin hit = .96
main hit = .995 (assuming of equal sail area)
Mast hit = .995

DPN = 71.4*.96*.995*.995 = 67.86

Given that the only difference between your boat and an F18 that rates 62.8 is the hull shape and the board aspect ratio (maybe weight?), I believe this is a very generous rating but a reasonable place to start.

So, your saying 71.2 x .995 x .995 x .995 = 70.1? This number seems a little high compared with the F18 62.0. The H18F has the lowest initial number of the TheMightyHobie18 classes at 71.2, lower means faster right?

given the Tiger sail total (main & large jib) is 227.5 sq. ft, and the Hobie 18 total is 240 sq. ft. (main/jib seperate size unknown and ~5% difference), I'd go

TheMightyHobie18 (71.4)
SP .96
MN .995
MT .995

for 67.86

H18F, where did that come from? The US made

Formula

was nothing more than a standard TheMightyHobie18 w/white powder coat in lieu of anodize.

Jake: Just for clarification, do you mean the PRO has the ultimate say-so, the ultimate responsibility to get it right, or both?

My experience is primarily at laid-back regattas, but...

Most people I sail with have no idea what their rating means or how the system works. Consequently, they report their numbers wrong (or not at all) during registration and expect the RC to figure it out. This drives the PRO/scorer nuts! Some PROs say they can only use the number reported on the registration. They don't feel they are responsible for inspecting every boat's equipment, knowing the rules for every class, etc. The net result of these two approaches is usually not good. I have never protested a competitor for this, but have approached the individual and encouraged them to report the problem. Even then, it's rarely resolved properly, but I just let it go.

I don't know the exact rule, and maybe it's something that must be spelled out in the SIs, but it would seem a lot easier for each competitor to learn the system and report his number properly (or risk disqualification), rather than have the PRO be responsible. Kudos to WindyHill for trying to figure it out!

While I agree sorting out handicaps and mods are quite a headache on the part of the PRO, someone who has fairness of the event in mind has to have authority of the application of the handicaps. I can think of several situations where a sailor self-managed handicap system could be a real mess.

That's not to say that every PRO is required to run out with a tape measure and a scale. You have to assume that people are being honest...but at the end of the day, the PRO is responsible for providing a fair contest.

.96 x .995 x .995 (note the .96, not .995, for the spin)...ends up with 67.9. Lower is faster. 67.9 is probably not a very accurate rating but a place to start (I believe this is what they used at CatFest last weekend). With a 67.9 if you were racing against F18s, they would owe you 7.8 minutes for every hour of racing. (3.4 minutes for a 30 minute race, etc.)

Jake,
It would seem that some hit should be applied for the self-tacking jib. Even though it is smaller it is much easier to tack, especially downwind under spin.
I feel I slow the F18 fleet down, so asked to be placed in open class at Catfest. I don't know what number they used, it doesn't matter. I felt like I left alot of the decision in their hands, which isn't fair to them. The 67.9 with me at the helm is probably a good number. I looked at the TheMightyHobie18 Formula number because it, like the SX, gets a spin with no penalty and the Formula doesn't spec manufacturer of the spin. Maybe, with the jib a 67.6 (.995 hit for jib)?

sorry for the thread hijack

Jake, Would you mind showing us this calculation please?

The rating system is not intended to be a personal handicap system but is designed to rate the potential of the boat (i.e. if Randy Smyth was sailing it). Your, my, or Joe Blow's skill should have no bearing on the rating. At the end of the day, lets find a way to do what most feel is fair. I think the number 67.9 or 67.6 as you mentioned is a fair starting point. If it looks like you're unfairly clobering guys with that rating or there is a lot of discourse, then let's talk about it again.

On the rating / time calculation; you use the handicap number with the following forumla:

CT (Corrected Time)
ET (Elapsed Time)
HC (Handicap)

CT = (ET/HC) * 100

For a one hour race with an F18 rating of 62.4 the corrected time will be (60/62.4)*100 = 96.15 minutes

For the Hobie18Thang at 67.6 the corrected time would be (60/67.6)*100 = 88.76 minutes

The difference is 7.4 minutes. Understanding that the numbers work out a little differently if the Hobie18Thang is finishing in 68 minutes, approximating an identical 60 minute finish gives you some basis for comparison. The F18 needs to better the 18Thang by a time around 7.4 minutes in a one hour race in order to beat it on corrected time.

Jake

Where in the rules does it say the PRO can protest a sailor's rating?

These are issues for the organizing authority , eg the regatta chairmnen, (who is not necesarrily the PRO) and the class representative .... not the PRO.

The problem you point out is that nobody has stepped up to organize the class... In this case... Open class. What group of individuals decides ratings issues for the region's open class.

If an F18 team showed up with the heavy sail plan and was racing lite.... Who does what?
IMO... It only comes to an issue if a sailor in the event protests the light team. The Organizing authority then holds the protest hearing and turns to the class rep for rules. The protest committe then makes a decision on the facts found and the printed rules.

Somebody in open class in your region has to have the authority to make decisions on ratings... So.. when the protest committe comes to the Open Class and says... OK... what are your ratings rules so we can decide the protest... They get an answer. If the sailor and the ratings committe disagree and it's not resolved before the regatta...the protest committe has no choice but to take the ratings committe answer.

The thing to do is to reach agreement on the rating before the regatta So the rating committe needs the time to go further up the chain to the National USPN and get an answer if necssary... It should not involve the regatta or the regatta staff.

Obviously, this is a stupid way to handle a ratings issue. Windyhill is trying to get it sorted out... It just needs to happen before the regatta at the class level.

In WindyHills situation... I would say... the boat is basically a one off design. The changes are too extreme to get a fair value for the rating. I would calculate a Texel or ISAF rating based on his actual measurments and then map it back to the USPN system to get a base PN number. As a one off boat... he will have to live the rating forever since his sailing skill will always be mapped to the one of a kind boat.

Mark

You have to take the spin hit because you are not sailing with the wings as a SX with spin is rated. You are racing an 18 with the mods Jake listed. At least this is thw way I see it. I would agree that you are better suited to the open class, not the F-18 class. Hope to see you in Columbia

I agree Jerome. . . but then there are those few sailors who know exactly what their number is to their modified boat, and intentionally provided a slower number. There are a few at every fun regatta. They get away with it. They get away with it time and time again 'cause they know they can and the host strongly discourages protests. They know it is wrong but still do it. Why have handicap racing if you don't enforce the rules? Someone ALWAYS gets screwed unjustly. It is only my opinion, but the open class handicap racing (Portsmouth corrected) model is broken, and for more than a few reasons.

Sorry for the rant, I'll get off my soapbox.

I may have been wrong to indicate the PRO in that responsibility. Perhaps it is the regatta organizer. We're never going to have an open class that is organized enough to HAVE an organization much less a rating committee. Ratings should be ultimately managed by the regatta's managing authority...I'm nearly certain it's written somewhere but I don't have the time to research it at the moment.

In the case of PHRF, I understand the organizing body to have a good deal of authority over the end result of the rating system. I've heard of instances where they even override rating certificates.

The RRS handles all of this, although as Jake says, some of these positions may not be manned at every event.

RRS 75.1 and 78.1 puts the onus on the sailors to make sure their boat is entered correctly and meets the rules, including ratings rules.

RRS 78.3 states that an event measurer shall report inconsistencies to the RC, who shall (as in, must) then protest the boat.

RRS 89 states that scoring is the responsibility of the RC. So, if the event is using a rating system, the RC is responsible to score it accordingly.

The NOR and SI guides in the RRS (Apx K and L), which are the responsibility of the OA and RC, repectively, include measurement sections that should be included for such events.

I did a quick scan of the RRS and don't see a specific reference to say whether the measurer is part of the OA, or RC, or who appoints the measurer.

In any case, I would always have the expectation that the person who enters a boat is ultimately responsible to enter the boat (and rating) correctly.

If they get it wrong, they should be asked to correct the problem. If they refuse, they should be protested mercilessly until they play along or go away, just as if they kept ignoring port/starboard rules.

Mike

For the record I will use the 67.6 number moving forward.
If I get the boat further sorted out I may return to racing F18s but for the time being I will request to be placed in the open fleet.
Rick, I will not be able to attend Outback this year. Medical expenses from my wifes cancer treatments are really setting me back and it would cost me approx $200 to attend, just out of the question at this time.

AAhhhh, The beauty of one-design and to a slightly lesser extent Formula racing.

J

What does that mean ? <img src=

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Jeremy's a Hobie dealer and wasn't been around for the horrible threads on that subject. I hope that we don't go down that road now, and let him have the pleasure of using the

search

function. If we start talking about the myth of SMOD and the brand wars, I'll start bleeding out of my eyes again. We all sail catamarans... let's leave it at that.

Any thoughts on the mathematical conversion from DPN to PHRF? Sometimes us northeast cats have to mix it up with leaners.

Sorry guys, I should have been clearer, didn't mean to start anything. Just saying that most of what I sail these days is one-design, and looking at Jake's cool calculation just made me realize how simple it is when I see a boat ahead of me to know where I stand. No manufacturer wars or anything, I'll sell anything with sails. I'm not picky, I sell from Pcats, Hobie, Catalina, Hunter, Ashby, Bic and any guy that walks through the door and wants to sell his boat. I do draw the line at power boats though. <img src=

alt=

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We all good? I want to keep my 4 remaining stars <img src=

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J

As someone who has suffered thru scoring large open fleets, may I say....

...THANK YOU, again, Jerome. Your attitude is a joy to behold.

may I also say that the open fleet situations are a microcosm of what is going on in the US:

We have a population who is either too busy trying to make enough money to get all the things they THINK they need, or too LAZY to bother...
...to learn about the system in which they live.
...So then, they either depend on others (such as pundits) to tell them what is going on and for whom to vote.
...And then, when someone comes along who realizes that the population is lazy and ignorant, they take advantage of the situation.
...And then, the people whine and cry, when it's their OWN FAULT that they're being taken for a ride.

Here's the deal:

People, the RC are VOLUNTEERS who are wired-out stressed just putting on the regatta. It's about as pleasant as a root canal. I am amazed that anyone can stand to run a race more than once, much less for years.

And to top it off, the people who come to the race want the RC to figure out what THEY should know, which is their OWN Portsmouth number. And bitch and cry about how the race is run, when they've NEVER run a race themselves, and refuse to spend the time to learn about Portsmouth.

The system is just fine. It's up to YOU, the RACERS, to make it work. The whole basis in Corinthian sailing is that it's SELF-POLICING.

This means that it's up to the RACERS:
--to be honest.
--to deal with EACH OTHER when someone isn't honest.
--to solve infractions on the water, but when you can't, then take it to the RC in a reasonable tone WITH EVIDENCE TO BACK ANY ASSERTIONS YOU MAKE. <<That means KNOW YOUR NUMBER.

BTW...if you build yourself a Frankenboat, it's absolutely incumbent upon YOU to know your mods and report them to the RC. Live with what you're dealt - you didn't have to change the boat.

I echo Jerome: Kudos to WindyHill for asking the questions.

FWIW, w.h.... take a harder knock than you think you should, 'cause it will quieten the whining. Somewhat.

Yup.

There are other rating systems like Texel that are measurement based. Then cross over to DPN using boats w/ matching measured rating. Finally, if folks in the open fleet aren't happy with the rating you worked up- Talk to them! I would rather race w/ folks glad to see me and my boat then have a killer rating that makes winning easy. Leave that BS to the leadboat crowd...

Duh, I didn't think of that. That's a great idea. Can somebody run a Hobie 18 with an F18 sailplan through Texel...or wait...is there a point? I'm not intimately familiar with the texel rating system but the Hobie 18 is going to come out the same as the F18 isn't it?

Your stars are safe from me, 'migo. Tell Gene I said

hi

and

drive safely home with your new boat.

He's going to be a factor in the 16 fleet again, I'd bet.

Try this: http://www.schrs.com/uploads/site/exe/SCHRSCalc2007.exe

Once you have a schrs figure calculate alternative system number using variance from a 'datum' boat eg.F18

Cheshirecatman

Will work on it. BTW- your estimate was pretty close.

I echo Jerome: Kudos to WindyHill for asking the questions.

Well said. In my focus to answer the

responsibility

question, I completely overlooked this obvious point.

WindyHill is doing exactly what he should, and more people should act that way (would make all the rest of the whining in this thread invalid)...

Mike

brucat

WindyHill is doing exactly what he should... But he is screwed!

the problem is... He needs SOME authority to give him the Good house keeping seal of approval... Without the OK Dokey... he is always screwed...

if he sails the boat very well and sails to his rating. that he calculates... the rating will be suspect ... he will win because by definition... he sailed the boat to his rating. and his wins will be viewed as a problem. (even though he sailed very very well) .....

The discusion will be... There is something wrong with his rating and it undermines his racing performance ...

On the other hand...

If he sails the boat very well and looses his shirt... there is also something wrong... he doesn't have a chance.

It's a no win situation as it stands.

He has a complicated ratings question. EMSA (I think organizes the region) should OK a rating by calulating, guessing, interpolating from texel... voodoo...Whatever they choose... But when all parties feel a fair consensus is determined... declare the rating... and that is the end of the story.

Everyone can race and the rating is a non issue. That is the goal... the rating is a non issue.