PHRF Consistency

sailorman44

Member
281
71
CT/FL
In an earlier thread about headsail adjustments Alex W provided a link to the NW PHRF  rating handbook. A cursory review of the handbook was a revelation in transparency. Here was a PHRF committee telling the sailors in detail how it does business. How base boat rating are derived, the process of how adjustments are are computed. I particularly liked how one off boats are treated. I might have archived a fair rating for my boat in 2 or 3 years rather than the 17 years it actually took.
 
I had always thought that my regional PHRF committee was one of the better ones. They are active, they review boats in the fleet regularly, they are responsive to appeals. After reading the NW PHRF handbook I have been looking at my PHRF committee more critically. One of the areas I examined is headsail area adjustments.
 
 
             Headsail Adjustments   
 
Spinnaker Class                                   Non-Spinnaker Class  


 
 LP/J Size Range      Rating  Adjustment         LP/J Size Range        Rating  Adjustment
Up to[SIZE=13.3333px]1.10                                     +7                      Up to 1.10                                      +16 [/SIZE]
Greater than 1.10 to 1.20          +6                      Greater than 1.10 to 1.20           +13 
Greater than 1.20 to 1.30          +5                      Greater than 1.20 to 1.30           +10 
Greater than 1.30 to 1.35          +4                      Greater than 1.30 to 1.40           + 7
Greater than 1.35 to 1.40          +3                      Greater than 1.40 to 1.48           + 4 
Greater than 1.40 to 1.45          +2                      Greater than 1.45 to 1.51            +1 
Greater than 1.48 to 1.51          + 1                     Greater than 1.51 to 1.55              0 
Greater than 1.51 to 1.55            0                      Greater than 1.55 to 1.60             -1 
Greater than 1.55 to 1.60          - 1                      Greater than 1.60 to 1.65             -2 
Greater than 1.60 to 1.65          - 2                      Greater than 1.65 to 1.70             -3 
Greater than 1.65 to 1.70          - 3                      Greater than 1.70 is adjusted proportionally. 
Greater than 1.70 is adjusted proportionally.
 
The table shows that a 155% jib has a neutral or 0 adjustment. If you have a smaller jib there is a credit, +7 for 
a 110% jib  If your [SIZE=medium] jib is larger there is a -1 adjustment for each 5% LP. [/SIZE]
 
[SIZE=medium]So given my I is 42,5 and my [/SIZE]J is 14 the sail area for my [SIZE=medium]100%  jib is 297.5. My [/SIZE]J is 14 so the 155% LP would be 21.7. The area of  
[SIZE=medium]the 155% jib would be 461. Note that I am using LP [/SIZE][SIZE=medium]instead of [/SIZE]J to compute sail area for the larger jibs because I don't know what 
[SIZE=medium]the foot would measure. The relative differences between jib sizes will be the same regardless[/SIZE]
 
[SIZE=medium]How much is 5%LP worth in sq ft.? Using the area of the 155% jib, a 160% jib would be 476 or 15 sq ft larger than the 155% jib. [/SIZE]
[SIZE=medium]Similarly a 165% jib would be 491 sq ft [/SIZE][SIZE=medium]or 15 sq ft. larger than the 160% jib. A 170% jib would be 506 sq ft or 15 sq ft. larger than [/SIZE]
[SIZE=medium]the 165% jib. [/SIZE][SIZE=medium]Pretty consistent. For each 5% LP the sail area increases by 15 sq ft.[/SIZE]
 
[SIZE=medium]Now let's take that consistent 15 sq ft and apply it [/SIZE][SIZE=medium]to the credit side of the sail area adjustment table. L[/SIZE][SIZE=medium]et's take that 15 sq ft and [/SIZE]
[SIZE=medium]divide it into the size difference between a 100% jib [/SIZE][SIZE=medium]and a 155% jib. The 100% jib is 297.5 [/SIZE][SIZE=medium]and the 155% jib is 461 for a difference [/SIZE]
[SIZE=medium]of 164 . Dividing the size difference of 164  by 15, the [/SIZE][SIZE=medium]penalty increase in sq ft for [/SIZE][SIZE=medium]each 5%LP, [/SIZE][SIZE=medium]yields a difference of 11 seconds [/SIZE]
[SIZE=medium]per mile.[/SIZE]
 
[SIZE=medium]So  the real credit of a small jib should be 11 seconds not the 7 seconds that [/SIZE]PHRF gives.
 
[SIZE=medium]As usual [/SIZE]PHRF gives less in credits than it takes in penalties.
 
[SIZE=medium]Another question about the headsail adjustment table is why do non spinnaker boats get a bigger credit than spinnaker boats. [/SIZE]
[SIZE=medium]Spinnaker boats already boats already have a built in rating penalty. My certificate shows a 15 second credit if I sail non [/SIZE]
[SIZE=medium]spinnaker and  because I sail with a 100% jib I get an additional 16 seconds credit?[/SIZE]
 
[SIZE=medium]Another thing, I thought there was a [/SIZE]consistent 19 second penalty for spinnakers but mine is only 15. Doing a quick look at various 
[SIZE=medium]certificate [/SIZE][SIZE=medium]I find that there is a range of 10 to 22 seconds. [/SIZE][SIZE=medium]Shouldn't the spinnaker penalty be [/SIZE][SIZE=medium]consistent[/SIZE][SIZE=medium]?[/SIZE]
 
[SIZE=medium]Anyone from [/SIZE]PHRF want to try to explain what is going on here?
 


 

ryley

Super Anarchist
5,501
656
Boston, MA
I imagine the difference in credits for your jibs based on spin vs non-spin is related to how often you use the jib in a race. since non-spin racers are using their jib on all points of sail, they get a larger credit for that. As the jib gets smaller, it's less useful on the downwind leg. ostensibly a spinnaker boat is only using its jib for half the race, so the credit is halved to reflect that it is most useful from a reach up to close hauled.

As to the spinnaker 'penalty,' I think you're looking at it backwards and should be looking at it as a 'credit' for cruising (non-spin) configuration and that the spinnaker config is the default. Then, the cruising credit changes based on whether the boat has masthead or fractional jibs, whether it can carry a 155 or is designed for a non-overlapping headsail, etc.

Here's the adjustment that PHRF-NE applies:

Cruising Handicap: (updated May 8, 2016)

• No free flying sails (includes no mizzen staysails of any kind) Adjust from
• Rig type Racing Handicap
o Normal masthead rig +12 spm
o Fractional rig 15/16 or more +12
o Fractional rig 7/8 to 15/16 +9 o Fractional rig less than 7/8s +6
o LP 135% or less Genoa standard +3 from Cruising

This is what happens when you look at adjustments as singular events rather than holistically. 

 

sailorman44

Member
281
71
CT/FL
I imagine the difference in credits for your jibs based on spin vs non-spin is related to how often you use the jib in a race. since non-spin racers are using their jib on all points of sail, they get a larger credit for that.  As the jib gets smaller, it's less useful on the downwind leg. ostensibly a spinnaker boat is only using its jib for half the race, so the credit is halved to reflect that it is most useful from a reach up to close hauled.
OK, that makes sense.

I agree that a smaller jib deserves more credit. I went through the PHRF lookup for non spinnaker boats with small jibs and found some and they did get the extra credit as shown in the headsail adjustment table.
 
However I also found that the non spinnaker credit for spinnaker boats was not consistent. The symetrical boats varied by a couple of seconds with no explanation. The fractional boats were dinged a lot more, as much as 7 seconds. Is this because they carry asymmetricals? Again there is variability within the group.
 
BOAT      RIG            JIB %    CREDIT
Aqua    masthead    150           22
Bag       fractional      90            15
She       fractional     100           18
Zig         masthead   155           20    
Se T      masthead   155            20
Seg       masthead    155           21
As to the spinnaker 'penalty,' I think you're looking at it backwards and should be looking at it as a 'credit' for cruising (non-spin) configuration and that the spinnaker config is the default. Then, the cruising credit changes based on whether the boat has masthead or fractional jibs, whether it can carry a 155 or is designed for a non-overlapping headsail, etc.

I think I am looking at it the right way. [SIZE=medium]I think of non spinnaker as the default as most of the boats racing [/SIZE]PHRF are non spinnaker.
Most of the boats at my club that race are non spinnaker, most of the boats in the weekend races are non spinnaker. Most of the boats at Off soundings are spinnaker but 25-30% are not. [SIZE=medium] Off Soundings attracts a more serious group of racers. Seems to me that most [/SIZE]PHRF races do the club races and ignore the more competitive venues to the detriment of sailboat racing.
 
[SIZE=medium]We think of spinnaker as default because that is the way we sail.[/SIZE]
 
Here's the adjustment that PHRF-NE applies:

Cruising Handicap: (updated May 8, 2016)

• No free flying sails (includes no mizzen staysails of any kind) Adjust from
• Rig type Racing Handicap
o Normal masthead rig +12 spm
o Fractional rig 15/16 or more +12
o Fractional rig 7/8 to 15/16 +9 o Fractional rig less than 7/8s +6
o LP 135% or less Genoa standard +3 from Cruising

A fractional rig gets less credit than a masthead rig? Seems to me it should be the other way around. These adjustments are for cruising canvas?
 

Somebody Else

a person of little consequence
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ryley

Super Anarchist
5,501
656
Boston, MA
 [SIZE=medium]I think of non spinnaker as the default as most of the boats racing [/SIZE]PHRF are non spinnaker.
That's simply not a true statement. ECSA and PHRF-NE both define their base boats with spinnakers, and then make adjustments from the base boat to get to a cruising handicap. Even the numbers don't work out - in ECSA and PHRF-NE, spinnaker boats outnumber non-spin almost 2:1. I'm sure it's the same in YRA as well.

However I agree that PHRF-NE's method for getting from one to the other is flawed and reversed.

 
That's simply not a true statement. ECSA and PHRF-NE both define their base boats with spinnakers, and then make adjustments from the base boat to get to a cruising handicap. Even the numbers don't work out - in ECSA and PHRF-NE, spinnaker boats outnumber non-spin almost 2:1. I'm sure it's the same in YRA as well.

However I agree that PHRF-NE's method for getting from one to the other is flawed and reversed.
We tried to get a rating for our practice Starboat to do the Tuesday  beer can series, what a mess 

 

LionessRacing

Super Anarchist
4,351
591
Myrtle Beach,
Many of the PHRF committees use a 3sec increment, so the NW 1 sec is unique in my experience.

PHRF NorCal has a similar guideline published to PHRF NE, having been rated by both, they get to pretty much the same numbers for a well known standard hull/rig. 

As regards "Fair", Life ain't fair, and there will always be horses for courses... 

15 kt Navigation buoy random leg courses are fun, 5 kt W/L not so much in our case. 

 

sailorman44

Member
281
71
CT/FL
That's simply not a true statement. ECSA and PHRF-NE both define their base boats with spinnakers, and then make adjustments from the base boat to get to a cruising handicap. Even the numbers don't work out - in ECSA and PHRF-NE, spinnaker boats outnumber non-spin almost 2:1. I'm sure it's the same in YRA as well.

However I agree that PHRF-NE's method for getting from one to the other is flawed and reversed.
Maybe you are right. I did a count of the ECSA non spinnaker boats and there are 92 out of 208. I have never seen anything in the ECSA rulebook that indicates that spinnaker is the default. The base boat ratings have both spinnaker and non spinnaker ratings. Does it matter weather it is a non spinnaker credit or a spinnaker penalty. I tend to think penalty because PHRF penalizes anything that makes your boat faster.

 
Anyone who signs up for a regional sailing association has to be a more serious racer. At my club there are 30 active racers, 6 of them are spinnaker boats. Of that 30, I am about  the only one who does races outside the club. 
 

ryley

Super Anarchist
5,501
656
Boston, MA
I have never seen anything in the ECSA rulebook that indicates that spinnaker is the default.
That's because the entire book defaults to spinnaker ratings. How do I know? Section III outlines how much to add to a boat's rating to come up with the non-spinnaker rating, and section 10 is almost an afterthought of how to deal with non-spin boats.

I also think it's time to retire the saw that PHRF penalizes anything that makes your boat faster, because there are clear examples where that is not the case. PHRF-NE, for example gives you a +6 (in 2019, it used to be +9) for converting from symmetrical spin to bow-tacked asym, then lets you 'spend' those seconds at -3 / 10% J sprit you put on. For some (not all), this results in a boat that is faster than it was, but with the same rating it had before. PHRF-NE also has redefined their "recreational" handicap to include below-deck furlers, which clearly give an advantage over above-deck furlers, especially of the design that were in use when the rule was first proposed.

On the other hand, Chesapeake PHRF wanted to ding my 25' boat -9spm for a redesigned rudder, so maybe it's not quite time to retire it after all ;)

But to your bigger point, I think there are a lot of historic adjustments that haven't kept up with changing materials, designs, and advancements. It's hard in a volunteer organization to get enough traction to keep everything up to date. In PHRF-NE, there's been a two year effort to revisit not only some of the credits and debits, but also some base boat ratings to try to understand if there are warranted changes - that's part of why they've reduced the asym credit from +9 to +6. I think on the whole most organizations try to do the best they can with what they've got, but as long as there's no central authority to help standardize the system, you'll continue to find local variances that just don't make much sense.

 

LionessRacing

Super Anarchist
4,351
591
Myrtle Beach,
you'll continue to find local variances that just don't make much sense.
If in fact anyone remembers why they were there in the first place... Arguably characteristic wind speeds are reasonable to use for assessing differences in LP, a 180% may have once made sense on LIS, but would rarely if ever be used on SFBay, such that a lower penalty for more sail might be found in an area where it was less likely to be beneficial. 

 

Alex W

Super Anarchist
3,325
315
Seattle, WA
Many of the PHRF committees use a 3sec increment, so the NW 1 sec is unique in my experience.
PHRF-NW uses 3 second increments, you can’t even get a rating here that isn’t a multiple of 3. 

It is occasionally annoying when we race and have a mix of BC and NW boats. My boat rates 73 in BC and 72 in NW and it would be nice to just have even ratings. 

 

LionessRacing

Super Anarchist
4,351
591
Myrtle Beach,
JimBowie said:
Is a +15 secs/mile increase in a rating based on only two known boats reasonable in a single setting?
Depends on a bit of other data... We collect the time to finish, & course length of all our races where it's a known distance, and then run it through analysis to look for boats that standout. Every boat can have bad days, when you sail to a lower speed than the average corrected time. The question, is whether it any has a consistently faster or slower speed than rating would indicate, and does it warrant adjustment.

If your two boats have consistently underperformed the fleet, while well prepared, well started, well sailed and in a variety of condition, there might be a rationale.

Alternatively the committee might look at the data and decide that various boats were under performing due to issues, other than their ratings... 

 For example in the "sunday brunch series of 2019" Lioness has been crushing 4/5 of the other boats that are rated much lower, often beating them boat for boat and often correcting out at a minute/mile better. That might be an indication that our rating was too high, except that we are simultaneously racing competitively with an Alerion 28, where we are rated the same 168; two very different boats  getting pretty similar times and validating our joint ratings vs the 4 other boats (Ranger 33, Tartan 3400, Catalina 34, J100) 

 
Last edited by a moderator:

sailorman44

Member
281
71
CT/FL
there will always be horses for courses... 

15 kt Navigation buoy random leg courses are fun, 5 kt W/L not so much in our case. 
I race E scowls in Florida and we do W/L. Makes sense in a one design fleet. With all the boats the same there are no tactical opportunities on a reach. Just a parade. In Connecticut I refuse to do any W/L races. It is a mixed boat fleet and my boat really likes a reach. I give up a big advantage if I do W/L

 

PaulK

Super Anarchist
Trying to determine ratings adjustments by comparing the rigs of different boats does not take into account the boats themselves.  As Lioness points out, they rate the same as an Alerion 28.  If the Alerion reduced foretriangle sail area by 10% it would have a much bigger effect than if Lioness did.    

 

sailorman44

Member
281
71
CT/FL
When I started this thread my main concern was the discrepancy between credit given and penalty taken for headsail adjustments in the spinnaker category. Applying  the penalty criteria to the credit adjustment I find that the credit for a 110% headsail should be 11 seconds not the 7 seconds that PHRF gives. It seems to me that PHRF consistently gives less credit than is reasonable and penalizes more than is reasonable.

 

dacapo

Super Anarchist
13,606
1,559
NY
When I started this thread my main concern was the discrepancy between credit given and penalty taken for headsail adjustments in the spinnaker category. Applying  the penalty criteria to the credit adjustment I find that the credit for a 110% headsail should be 11 seconds not the 7 seconds that PHRF gives. It seems to me that PHRF consistently gives less credit than is reasonable and penalizes more than is reasonable.
split the difference  make it +9 sec. which is what YRALIS gives for a 110% jib

LP / J %                Adjustment

greater than 195 -15

greater than 185, to 195 -12

greater than 175, to 185 -9

greater than 165, to 175 -6

greater than 155, to 165 -3

 greater than 145, to 155 0

greater than 135, to 145 +3

greater than 115 to 135 +6

greater than 95 to 115 +9

up to 95% +12

 

Meat Wad

Super Anarchist
JimBowie said:
"PHRF Consistency".  Haha.  Oxymoron.  Like "Military Intelligence".
The real problem is we have no National direction.

US Failing has abdicated itself from any PHRF Responsibility, while claiming to be the National Authority. Why does US Sailing not have a national prescription for PHRF Boat, RIg and Sail Measurements....IE...Equations??  Her is the joke of our national authority https://www.ussailing.org/competition/offshore/phrf/

Why is there no consistency across the great nation?

Personally, I think several areas should file lawsuits against US Sailing over this failure to regulate the sport at the national level.

Maybe it would break up US Failing. As a west coast sailor, I see no reason to be part of the national authority that does not care about anything except it east coast authority.

Is the worthless World Sailing Listening?? HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA HA 

 




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