PHRF - Spin vs. Non-Spin Adjustment

Apr 21, 2015
127
Catalina 22 Sport #15582 Indianapolis
For PHRF racing, what are your thoughts on applying a credit (adjustment) for non-spinnaker that is based on a percentage of a boat's Base PHRF rating instead of a flat credit of 12 seconds across all non-spin boats?

A high PHRF rated Precision 23 would receive a non-spinnaker credit (adjustment) equal to 7% of the Base PHRF rating, and a lower PHRF rated S2 7.9 racing non-spin would also receive a credit (adjustment) equal to 7% of its Base PHRF rating.
Pros?
Cons?
Thanks.
 
Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
On what basis is the flat-rate adjustment? How is the percentage value determined? How is it determined now in he sec/mile credit? For example, one could argue that the boat reducing sail area by a greater percentage should receive a greater credit, etc.
 
Last edited:
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
I think I would like it if I were the Precision 23. Is the premise that slower boats lose more than faster boats by sailing non-spin? Is that the case? I could say that slower boats tend to be lighter and may do better in light wind. Or may plane in windier conditions (Yeah, planing is a problem either way). I'm not defending the one size fits all approach but I must be missing the point of this.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Nope.

Two reasons.
First, a PHRF ratting is not zero based, which if it where would make a percentage make more sense. Under your model, a very fast boat with a rating of 70 would get a tiny 4 second bump for going non spin. And a boat with a 0 handicap would get nothing.

Second, non-spin handicaps are based on the boats actual performance without a spinnaker. You can't just reduce the number by a flat amount.
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
Geez. A PHRF "Discussion" is over in four posts? The wind is howling outside. The rain is horizontal. We're advised to stay put so a tree doesn't fall on us. Can't we do any better than that? I can go into our local sailing hangout and just say "PHRF" and there will be a two hour argument.
Our fleet handicapper does a 20 "Sec" adjustment for non-spin. It doesn't really matter since there are few situations where spin and non-spin boats are scored together. Sometimes an overall trophy but those are pretty meaningless, when boats don't start together and sail different races in terms of wind and tide conditions. The correction could be 12 seconds or 30 seconds. I don't see how it matters.
 
  • Like
Likes: Parsons
May 17, 2004
5,028
Beneteau Oceanis 37 Havre de Grace
Looking at the PHRF Chesapeake valid list it looks like they apply an adjustment anywhere from 3 to 12 seconds for non-spin. Like Jackdaw said, it really should be a performance based adjustment which is hard to match with a flat rate or a flat percent.

What I'm curious about is if that type of adjustment is really meant to make a spin vs non-spin race competitive. I don't see how a 12 second adjustment could do that. For example, in a race 1 mile upwind and 1 mile downwind, if the non-spin boat goes 4 knots downwind, the spin boat would only need to go 4.1 knots to make up for the handicap. Surely the spin boat would go more than 0.1 kt faster downwind.

I assume instead that the different ratings aren't meant to be compared, but that they allow boats within the same configuration to compete. Think of 2 boats, A and B. A has a small jib. B has a large genoa. A's non-spin performance is expected to be poor due to the small jib, so she gets a bigger non-spin adjustment than B. Both boats would be slower non-spin than spin, but the amount by which they're slower doesn't matter, only how their performance rates against others in the same configuration. Do I have this right?
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Looking at the PHRF Chesapeake valid list it looks like they apply an adjustment anywhere from 3 to 12 seconds for non-spin. Like Jackdaw said, it really should be a performance based adjustment which is hard to match with a flat rate or a flat percent.

What I'm curious about is if that type of adjustment is really meant to make a spin vs non-spin race competitive. I don't see how a 12 second adjustment could do that. For example, in a race 1 mile upwind and 1 mile downwind, if the non-spin boat goes 4 knots downwind, the spin boat would only need to go 4.1 knots to make up for the handicap. Surely the spin boat would go more than 0.1 kt faster downwind.

I assume instead that the different ratings aren't meant to be compared, but that they allow boats within the same configuration to compete. Think of 2 boats, A and B. A has a small jib. B has a large genoa. A's non-spin performance is expected to be poor due to the small jib, so she gets a bigger non-spin adjustment than B. Both boats would be slower non-spin than spin, but the amount by which they're slower doesn't matter, only how their performance rates against others in the same configuration. Do I have this right?
Exactly. PHRF non-spin ratings are NEVER to be used to allow non-spin boats to race spin boats in a single race. The ratings show the relative difference between boats in simular configurations. They always need to be scored separately, and in well written PHRF rules it will say so.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Geez. A PHRF "Discussion" is over in four posts? The wind is howling outside. The rain is horizontal. We're advised to stay put so a tree doesn't fall on us. Can't we do any better than that? I can go into our local sailing hangout and just say "PHRF" and there will be a two hour argument.
Our fleet handicapper does a 20 "Sec" adjustment for non-spin. It doesn't really matter since there are few situations where spin and non-spin boats are scored together. Sometimes an overall trophy but those are pretty meaningless, when boats don't start together and sail different races in terms of wind and tide conditions. The correction could be 12 seconds or 30 seconds. I don't see how it matters.
He should never do that, because the results will be meaningless. Most PHRF board rules specify prohibit the two fleets being scored together.

The places I've seen it done boats will choose fleets to try and game the race based on course or expected wind.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Jackdaw...where are the PHRF Board Rules you refer to per your input above? Is there a website URL that has the official PHRF rules that you could possibly share? I have looked all over the US Sailing website, and many popular PHRF and it makes no reference to "PHRF Rules"...just PHRF ratings. Anything you could share to direct me to your official PHRF Board Rules would be very much appreciated.
Thanks.
OK, I was going to leave this as homework for the student, but I'll help you out a bit.
Goto the webpages the major PHRF fleets; New England, Southern California and Northern California, Chesapeake, etc. All of them will say (in one way or another) that the ratings for spin and non-spin are not designed to allow the two fleets to sail against each other in a race. The NoCal PHRF (where PHRF was born) fleet rules actually says that they know of no way to rate the two fleets together fairly. Any good PRO will know this as well.

http://www.yra.org/PHRF/docs/ncphrf_rules_and_guidelines.pdf
 
Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
Well, there's this from a recent So. Cal. NOR of 2015 for a local club's Wet Wednesday. I doubt it's a violation of So. Cal. PHRF class rules although it does say CHRF, not PHRF.

"CLASSES: Two CHRF classes are planned. The CHRF class is open to all mono-hull boats. Class A is for boats with PHRF ratings of 132 and below. Class B is for boats with PHRF ratings of 133 and above. The CHRF class will mix spinnaker boats with base PHRF handicaps and non-spinnaker boats using the PHRF Non-Spinnaker offset. The intent is that non-spinnaker racers should be encouraged to give spinnaker racing a try at some point during the series. Skippers must report to the RC boat each week whether they are racing spinnaker or non-spinnaker."
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Well, there's this from a recent So. Cal. NOR of 2015 for a local club's Wet Wednesday. I doubt it's a violation of So. Cal. PHRF class rules although it does say CHRF, not PHRF.

"CLASSES: Two CHRF classes are planned. The CHRF class is open to all mono-hull boats. Class A is for boats with PHRF ratings of 132 and below. Class B is for boats with PHRF ratings of 133 and above. The CHRF class will mix spinnaker boats with base PHRF handicaps and non-spinnaker boats using the PHRF Non-Spinnaker offset. The intent is that non-spinnaker racers should be encouraged to give spinnaker racing a try at some point during the series. Skippers must report to the RC boat each week whether they are racing spinnaker or non-spinnaker."
Yea that's a CRUISING handicap fleet, and thats a nice way to let typically non-spin boats 'dip their toe in the water'.

But you can't use it for serious racing. The rule just begs to be gamed, with the allowance for boats to declare what fleet they will sail in right before the race. If it looked 80% upwind, hell I'd take the time credit and race non-spin too!
 
Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
Yea that's a CRUISING handicap fleet, and thats a nice way to let typically non-spin boats 'dip their toe in the water'.

But you can't use it for serious racing. The rule just begs to be gamed, with the allowance for boats to declare what fleet they will sail in right before the race. If it looked 80% upwind, hell I'd take the time credit and race non-spin too!
I investigated a little further, CHRF apparently means Club Handicap Racing Fleet, for what it's worth.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Lake Michigan PHRF says:

The Non-Spinnaker Handicap (NSHCP) is an auxiliary handicap. This handicap reflects the change in relative speed potential of a boat that races without deploying a spinnaker. The handicap is commonly referred to as the Jib and Main (JAM) handicap. The NSHCP should only be used when racing boats racing without spinnakers; it is not developed for use in racing against boats deploying spinnakers.
 
Feb 2, 2006
464
Hunter Legend 35 Kingston
Ditto from the PHRF-LO site:

"Since PHRF does not run regattas it leaves the decision of fleet make-up to the race organizer. A club is well within its charter to set specific limits as to the specific boat types it will allow to race in any race or division. Furthermore, PHRF does not endorse racing spinnaker boats with non-spinnaker boats nor does it endorse racing displacement hulls against planing hulls but if an organization desires to do so, then they accept a much higher potential handicap error."
 
Apr 21, 2015
127
Catalina 22 Sport #15582 Indianapolis
Ditto from the PHRF-LO site:

"Since PHRF does not run regattas it leaves the decision of fleet make-up to the race organizer. A club is well within its charter to set specific limits as to the specific boat types it will allow to race in any race or division. Furthermore, PHRF does not endorse racing spinnaker boats with non-spinnaker boats nor does it endorse racing displacement hulls against planing hulls but if an organization desires to do so, then they accept a much higher potential handicap error."
Very nicely stated...thank you!
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Ditto from the PHRF-LO site:

"Since PHRF does not run regattas it leaves the decision of fleet make-up to the race organizer. A club is well within its charter to set specific limits as to the specific boat types it will allow to race in any race or division. Furthermore, PHRF does not endorse racing spinnaker boats with non-spinnaker boats nor does it endorse racing displacement hulls against planing hulls but if an organization desires to do so, then they accept a much higher potential handicap error."
Indeed. That's because the highet level PHRF boards recognize that at the end of the day it's the local clubs that set the Sailing instructions for any particular race. And they can do what they want. I see clubs race Monohulls against catamarans in PHRF as well, another not so great idea but I know the clubs are just trying to foster more racing. Never would say that's a bad thing, even if the results are wacky.
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
I've had the flu and am just getting back to this thread. Much has gone by that it isn't productive to go back to. I will say I was wrong - our racing doesn't ever score spin classes with non-spin. We do allow boats to choose spin or non-spin on the day of racing, in a series of races, and Jackdaw is correct that skippers game that. This is club level racing and we do want participation. It's not "Serious" other than we try to create a positive experience for the sailors.
We've gotten away from the OP, which was about how to translate a spin rating to a cruising rating. I did not understand Jackdaw's post that included "Zero based" ratings. I don't know what that means. Could you explain?
 
May 17, 2004
5,028
Beneteau Oceanis 37 Havre de Grace
We've gotten away from the OP, which was about how to translate a spin rating to a cruising rating. I did not understand Jackdaw's post that included "Zero based" ratings. I don't know what that means. Could you explain?
I think Jackdaw was saying that because The PHRF scale doesn't "start" at 0, it wouldn't work to assign a non-spin adjustment as a flat percentage of the PHRF handicap. Let's say you thought giving a 20% adjustment for non-spin was a good idea. How would you adjust a boat with a base rating of -12, for example? Give them a negative non-spin adjustment, down to -14? That just wouldn't work - non-spin shouldn't owe time to spin. Give them the absolute value of the 20%, bringing them up to -10? Well that doesn't work either because then your giving them a bigger bump than a boat with a base rating of 3. A flat percent adjustment just doesn't work in those cases.

So then you start to think about what kind of adjustment would work. Maybe you could just add a set amount to the base, like always adding 12 seconds/mile. But then that doesn't work either because not every boat has non-Spin performance consistent with its spin performance. A boat with a small headsail will be slower in non-spin than a boat with a genoa, even if their spin ratings are the same. So we can't use a flat rate either.

So then if a percentage doesn't work, and a flat rate doesn't work, why not try a performance based rating unique to each boat? So if a boat has a small headsail it gets a bigger non-spin adjustment than a boat with a genoa. Works great, right? Well, only until you have a race that's more upwind than down. Then the boat that got the bigger adjustment for being slow downwind is now getting that big adjustment on the long upwind leg too. And if the race is more downwind than up, then that boat isn't getting well enough compensated for its slow downwind performance. Racers will game that and choose their configuration based on the course.

And that is why PHRF just doesn't work to compare spin and non-spin boats consistently.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
David pretty much got it.

Ever hear someone say that because its 100F in Tucson, and 50F in Minneapolis, and its TWICE AS COLD in Minneapolis?? No its not, because zero F is arbitrary.

Same in PHRF. Zero is arbitrary. A boat with a PHRF of zero is really doing a mile of course in 660+0=660 seconds. A boat with a rating of 201 does a mile in 660+201=861 seconds.

Those number might make a better percentage basis. But its still wrong.
 
Last edited: