PHRF ratings on sportsboats

WCB

Super Anarchist
4,727
1,021
Park City, UT
Well, I seem to remember that base ratings should not be changed more than 12 sec/mile annually. Since neither of these has been raced in your local venue, be careful assigning their provisional rating. Once you find a similar rated location (mountain lake), use the stock PHRF and make following adjustments:

1. Square headed main, -6 sec/mile minimum. That's a big factor projecting extra area at the top.
2. Oversized kite, -6 sec/mile minimum. Depending on the estimated percentage bigger (than stock), could warrant -12 sec/mile.

So generally, the Hobie gets knocked from -12 to -18 seconds/mile and the Ultimate comes with square headed main, so leave her alone.
Funny update. Another Hobie Magic 25 showed up (it was there but not being sailed) and the owner looks at the first one with the square head main and larger spinnaker and says something to the effect of, "I didn't realize that your main was so big, I think that we need to adjust your rating".
 
@JulianB I completely agree, our local rating system has completely decimated any enthusiasm or hope that sportboats can be competitive. The group that runs the rating system is opposed to accepting any evidence that their system is flawed. They regularly monitor this board and will jump in and aggressively argue in favor of their system. I've had to block all of them just to even participate in these discussions.

From what I've seen one of the big problems is the belief that the VPPs that are developed are "scientific". For example, our rating system offered to look deeper at my boat design. After a few weeks the offered a 1.5% correction. I told them thanks but no-thanks. I wasn't going to validate what they did by accepting the new joke rating. Unfortunately my sister boat accepted it. None of our measurements changed. So the only way they could have come to a new rating was if they way they calculated changed. And if this is the case then why didn't everyone else's ratings change too after a recalculation? Because what they do is not a single algorithm. There are so many on-off subjectively tuned ratings done. This isn't a VPP anymore, it is yardstick.

The other problem is that our rating system claims they have experts in naval architecture developing these ratings. I come time find out they're a bunch of retired boomers that only are familiar with heavier displacement boats. They don't know what the fuck they're doing when it comes to planing hulls.

All this to say, I do not see any path forward for existing rating systems. They're too political and they're reputation, ego, and money makers for many. There needs to be a a CFD simulated approach that relies on a *single* way to evaluate all boats.
 
Let me be a bit more concise, pretty much all existing VPP and yardstick rating system play ratings whack-a-mole. They talk a lot of shit about being scientifically based to sell you on their system but then will quickly get into the game of "let's try this rating, oh that didn't work let's try this rating". This is a bullshit and half-ass approach that is killing this sport.
 

WCB

Super Anarchist
4,727
1,021
Park City, UT
Let me be a bit more concise, pretty much all existing VPP and yardstick rating system play ratings whack-a-mole. They talk a lot of shit about being scientifically based to sell you on their system but then will quickly get into the game of "let's try this rating, oh that didn't work let's try this rating". This is a bullshit and half-ass approach that is killing this sport.
This is like reading any issue of Seahorse magazine. In general it's a great read for sailing but there's always one or two articles in every issue where they compare how great IRC is over ORC. They should have to mark the pieces as paid advertisements or opinion pieces.
 
@WCB that's what I've come to understand, it's a business and there is profit motive which I think is bad for sailing. There needs to be an open VPP that everyone can scrutinize. The current rating systems will bitch about this leading to people optimizing their boats on the margins but if that is possible in a given VPP then the VPP is not a good one. It should be impossible to do this unless there is a ton of subjective allowances for given classes that can be taken advantage of
 

JulianB

Super Anarchist
1,388
2,094
Sydney mostly
Let me be a bit more concise, pretty much all existing VPP and yardstick rating system play ratings whack-a-mole. They talk a lot of shit about being scientifically based to sell you on their system but then will quickly get into the game of "let's try this rating, oh that didn't work let's try this rating". This is a bullshit and half-ass approach that is killing this sport.
Hi bcardarella,

My father generated a sort of VPP, but very much for HP planning boats, it's a very large excel doc and use's radians and all sort of other interesting formulas which I have no hope of following, but it was pretty good at working out what would happen with changes to the 49er and 29er. It also split the working sail into 4 sections, the jib into 3 section and very wind (AWS) dependent, so it was and is a very useful tool for predicting up-wind performance if we alter something. Did not touch down-wind and a lot of that is still a black art.

I still use it if I have a issue, it's not dated, but it's on floppy discs, Dad died 2012.

I even used it's basic parameters to do a graphic representation of Int class boats (dinghies/skiffs) which has been published on these pages before, and I still stand by that, its at-least 5 years old now, probably older.

Having just gone through a pretty extensive sail re-evaluation process with the 49er/FX, WRT down-wind, we keep on reducing spinnaker area and going faster and no VPP that I know will come up with that answer. So I have little faith in VPPs or rating systems based on any VPP.

I'm 65, I'm a month from launching my boat, I wanted to pull-back but I owe some really great people some of my time, Ellen must be regretting the day she asked me to help her, and the list goes on. Yesterday we sort of committed to 7 away events and something like 20 local events.

All I want to do is go sailing, with my mates, drink great red wine and eat some sensational food, again drinkers with a sailing problem.

But I am spending a lot of my time these days helping Brazilians re-birth their boats, because this logistic nightmare that has beset the world means no new boats in Brazil, exasperated by decisions made without thinking of the consequences. And Brazilians don't buy from Argentinian's, (politics) and I am also helping Asia (the Ellen reference above, also Penny) so ratings is quite low on my "to do list".

I do have some really smart friends, Peter, Brodie and with any luck I will get to meet Malav in Dubai in the next few weeks.
Peter got stung by the PHS process in Hamilton recently, then you have Rob (multi-hulls) and he is a) reading this, so b) also smart and that system which I thought was a great starting point (OMR) is now also being gamed.

At the end of the day, we just want to go get wet and have some fun (and in my case drink red wine and eat food with mates) so VPP's and IRC and ORC are all great and worthy causes for those that want to get into them, and there are lots of people that want to do that and all power to them, and they should go for that. To try and extend that down into Ma & Pa Kettle for a Sunday race out of the local club is absurd and really a waste of time and effort.

If you have a 10 year old XYZ boat with 10 year old sails and you want to go race against a brand new XYZ boats with brand new sails then the only "rating" system that has any chance of getting it even remotely right is a PHS. CBH dose not compensate for new hull or new sails or if it dose it's subjective. IRC and ORC to the best of my knowledge will also have to "compensate" otherwise know as age allowance.

And at the risk of repeating myself the systems that work well in other sports are PHS base, they also allow you to go sailing by yourself and allow you to try and achieve PB's. The failing of PHS at the moment is it can also be gamed (and is) so someone needs to do the work and incorporate (again at the risk of repeating myself) the golf process or the swimming or the horse racing or the etc etc.

Here in Australia, the Sportsboat community is voting with their feet, and avoiding the SMS and opting for PHS (& CBH) systems.

I have not looked into CBH so I really can't comment other that being committed to getting one.

My prediction is if you modify PHS with a decent sampling protocol, it will become THE benchmark system.

jB
 

firstlast

New member
10
3
When looking at handicap ratings, I don't have a lot of experience. I do prefer to sail one design but it can't be helped at one of the venues I sail as we're still building the fleet.

Two of the boats have square head mains and I was wondering, what kind of ratings hit would that be? Also, one of them seems to be sailing a larger spinnaker too. How does one handle this correctly, i.e. do you measure the sail and send the measurement to a third party for them to determine the rating adjustment?

This is why I like one design...ugh, but I feel like it should be handled openly so that everybody stays happier about competing fairly.

Boats:
Melges 24s - stock
Hobie 25 - Square head main and larger spinnaker
Ultimate 24 - Square head main and looks to be stock spinnaker
Suggest you contact Youngstown (NY) Yacht Club. They sponsored the YYC Levels for 40 years on Lake Ontario (The last one was 2013.) This included one design/PHRF. There were various boats all sizes and shapes. There were five starting areas to accommodate all the boats and classes. Someone there may be able to help solve your conundrum.
When looking at handicap ratings, I don't have a lot of experience. I do prefer to sail one design but it can't be helped at one of the venues I sail as we're still building the fleet.

Two of the boats have square head mains and I was wondering, what kind of ratings hit would that be? Also, one of them seems to be sailing a larger spinnaker too. How does one handle this correctly, i.e. do you measure the sail and send the measurement to a third party for them to determine the rating adjustment?

This is why I like one design...ugh, but I feel like it should be handled openly so that everybody stays happier about competing fairly.

Boats:
Melges 24s - stock
Hobie 25 - Square head main and larger spinnaker
Ultimate 24 - Square head main and looks to be stock spinnaker
Perhaps you may want to contact the Youngstown (NY) Yacht Club. "yyc.org". For 40 years (Ended 2013)they sponsored the Youngstown Levels regatta on Lake Ontario. This event was so large that five starting circles (Gates) were necessary. The entire fleet was broken down to one design/PHRF with numerous classes. Some one at YYC may be able to hep you solve your conundrum.
 
@JulianB I've thought about PHS systems. I was considering approaching this from the direction of skipper/boat combo handicaps. Similar to golf. You have to sail a bit to build up a sample size of how you as the skipper manage to perform in a given boat over different wind ranges. The issue here is that for some this may take a very long time to build the sample data.

The math exists to know how boats should perform under different conditions. The issue is that CFD sims are incredibly slow and have not been practical for anything but high ROI efforts. This is on the cusp of changing. Without getting too much into the weeds some academic research in the direction of tensor-based CFD sims (a.k.a. machine learning / AI derived) + distributed systems. This should yield much faster render times which would make it reasonable to iterate through wind ranges and trims then use a polar interpolation to fill in the gaps. However, still a few years out.
 

JulianB

Super Anarchist
1,388
2,094
Sydney mostly
@JulianB I've thought about PHS systems. I was considering approaching this from the direction of skipper/boat combo handicaps. Similar to golf. You have to sail a bit to build up a sample size of how you as the skipper manage to perform in a given boat over different wind ranges. The issue here is that for some this may take a very long time to build the sample data.

The math exists to know how boats should perform under different conditions. The issue is that CFD sims are incredibly slow and have not been practical for anything but high ROI efforts. This is on the cusp of changing. Without getting too much into the weeds some academic research in the direction of tensor-based CFD sims (a.k.a. machine learning / AI derived) + distributed systems. This should yield much faster render times which would make it reasonable to iterate through wind ranges and trims then use a polar interpolation to fill in the gaps. However, still a few years out.
Some years back we fooled around with a quite basic App. It still exists.

All you do is log on, throw the phone in your spin bag pocket or what ever and it.
a) tracks you
b) logs the current wind speed and direction which it gets off
i) a on board anemometer or
ii( the dark cloud (great name) so it will pick the closest anemometer (airport, in Sydney the Wedding Cake or North head) to you.
c) at the end of the your sailing outing it will give you a bunch of information.
1) your PB's for the day for the Wind strengths you experienced
2) You PB's being the % you where able to achieve of your max PB for that day and your max PB ever
3) Your outright max's for the windspeed you sailed in ( we picked 2,3,4,5 & 6 of the Beaufort Scale
4) it would also give tacking angles, gybing angles etc etc

So if you took that and optimized it, and people started logging their outings, within a very short space of time you could have a very accurate PHS system.

Now I have no doubt that there are now plenty of Apps but the issue is getting people to actually do it.

I am heartened by my club (SASC) has a fleet which do just this, but equally I am 1000% sure people will try and game it.

jB
 

neuronz

Anarchist
929
102
europe
Hi @JulianB, have you had a look at the SAP sailing stuff. I think it is already halfway there, only the rating adjustment part is missing.

We are using it for beercan racing. Every competitor simply has a phone on board with an app that continuously sends position updates to the server. The thing knows where the startline and race marks are and in the end the results are automatically calculated based on the assigned ratings, no race committee needed. You can even review the race and tracks of all competitors and I think if you have a subscription you can look at basic performance statistics. Should not be too hard to add the rating adjustment, however I believe the hard parts will be accurately determining windspeed and figuring out the corresponding boatspeed. I tried analysing the liveline performance data from the AC in San Francisco a while back and it was a mess. You could basically have any boatspeed at any given windspeed and with a GPS based system you will have lots of noise so filtering will be an issue
 

Streetwise

Super Anarchist
1,730
77
Lake Champlain
The National Reference Ratings are from a VPP program that US Sailing has. This includes the Melges 20, Melges 24, J/70, and Viper 640. Those are in the spreadsheet that I shared. The Henderson 30 has one too, but I was only looking at the 19 to 24 foot range for my data collection.

I got our PHRF committee to standardize all the boats with NRRs. They also provide useful benchmarks for figuring out the rating of boats that are in-between.
 

Aquila11

New member
25
14
MA
My father generated a sort of VPP, but very much for HP planning boats, it's a very large excel doc and use's radians and all sort of other interesting formulas which I have no hope of following, but it was pretty good at working out what would happen with changes to the 49er and 29er. It also split the working sail into 4 sections, the jib into 3 section and very wind (AWS) dependent, so it was and is a very useful tool for predicting up-wind performance if we alter something. Did not touch down-wind and a lot of that is still a black art.

@JulianB

Sounds like your father was Frank? I'm reading his High Performance Sailing book now. It's fantastic!
 

JulianB

Super Anarchist
1,388
2,094
Sydney mostly
@JulianB

Sounds like your father was Frank? I'm reading his High Performance Sailing book now. It's fantastic!
Had the very great good fortune to have my mother Nel, and my father, Frank and the even greater fortune to be the youngest so I had them to myself effectively for the last 20years of their lives. Mom and I were Dad's editor's. We made him learn Word and typing for his 2nd book. (His handwriting was a horizontal line with squiggles) 1st book is very heavy, surprised it sold in such number, 2nd book is the best one, I think, anyway, much easier read.
 

Steam Flyer

Sophisticated Yet Humble
47,964
11,658
Eastern NC
Sailors everywhere were starving for a intelligent and intelligible explanation. Bethwaite and Marchaj are both on my bookshelf within arm's reach of where I'm sitting right now.
 

Goodvibes

under the southern cross I stand ...
2,291
790
we rate 87 with our PHRF-LO rating on a melges 24.

its kinda rough
And that right there is the problem.

Sorry but as a former handicapper, every time the boat does not end up on top the owners complain about the ratings. Their failure to win is all the proof needed to claim the ratings are wrong. It's as predictable as the sun coming up tomorrow.
 


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