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Can ORR/ORR-EZ Rating System allow diversity?


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I’m the owner of a Corsair 24’ long Sprint 750 trimaran that we sail and race on the Gulf coast. We have a PHRF rating of 33 that we use not only when racing other trimarans but we also use it for some local club racing in mixed fleets. The rating in my opinion is actually quite fair relative to other performance sportboats in PHRF. In light air (under 10 knots), we have to work our butts off to correct against any well sailed displacement monohull especially if there is any significant amount of dead downwind sailing. When the wind builds solidly above 12-14 knots, we have to be pretty sloppy not to win and I have offered to sail at a lower rating and had one instance where a PRO dropped our rating on the water 10 minutes before a distance race start and notified us via a chase boat! I’ve always contended that if PHRF could be modified to be a multi-rating rule, it could close the gap to allow our boat to mix it up as well as also making other performance sportboats ratings more accurate and fair. For the most part, these calls for logic and getting more boats sailing has fallen on deaf (perhaps prejudiced) ears.

The ORR/ORR-EZ rating system appears to be gaining momentum and it’s use of up to four ratings for different wind strengths would seem to open the door to what I think is possible in allowing our boat to be rated fairly against both displacement monohulls and performance sportboats.

I’ve taken a quick look at the ORR website and there is nothing to suggest this could be possible or has been tried.

Why not I would ask if it gets more participation on the water?

Cheers.

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AClass,

to my knowledge, there is still a split between monohulls and multihulls in ORR/Ez, I know ORA has done some ORR/Multihull work, but the last time I asked it was not their intention to allow MH and monohull comingled racing. I'll see if there is any movement on that.

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Diversity? O.  I thought this was a controversial political thread on PA.  Never mind. Back to normally scheduled programming.

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You are fighting a non linear problem with linear tools: 

PHRF and other ratings with VPP's work reasonably well for incremental conditions over moderate ranges: 

  • Nobody Planing 
  • Everybody Planing/not Foiling
  • Everybody Foiling

Trying to rate when some people are foiling and others are in displacement mode would be very difficult, due to hysteresis, and the problem of picking which number(s) to use based on Wind speed(s) at time(s) & location(s) 

for a 1 mile W/L course that could be done at the starting line, for a 100 mile random leg course or a pursuit start it's a  lot harder. 

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47 minutes ago, LionessRacing said:

You are fighting a non linear problem with linear tools: 

PHRF and other ratings with VPP's work reasonably well for incremental conditions over moderate ranges: 

  • Nobody Planing 
  • Everybody Planing/not Foiling
  • Everybody Foiling

Trying to rate when some people are foiling and others are in displacement mode would be very difficult, due to hysteresis, and the problem of picking which number(s) to use based on Wind speed(s) at time(s) & location(s) 

for a 1 mile W/L course that could be done at the starting line, for a 100 mile random leg course or a pursuit start it's a  lot harder. 

Trimarans do not foil. Make sure you are not confusing a trimaran with a foiling catamaran. Small beach or foiling catamarans are not pertinent to this discussion.

Corsair trimarans are very, very similar to a planing sportboat (i.e. think Melges 24/32 in comparison) with the primary difference being our righting moment comes from the floats rather than a bulb keel on a fin. At a certain hull speed, the center hull will plane just as a sport boat hull does after it exceeds hull speed.

We did a 100 mile distance race from Gulfport, MS to Pensacola, FL several years ago. The start was a mass start and the conditions were 5-12 knots for the entire race. We pretty much sailed boat for boat with a J-111 helmed by Olympic silver medalist Johnny Lovell for the entire race (36’ monohull sportboat versus 24’ trimaran). We beat them by about 10 minutes elapsed, they corrected out on us by 12 seconds. This turned a lot of heads at the time that the boats could race against each other. I will say that if the breeze would have been 10-15 knots, we would probably would have beaten the J-111 easily, thus multi-rating based on the performance of the boat in different wind conditions would be applicable. 

Our boat pretty much sails the same downwind angles as the sportboats (90-100 degrees apparent). It tacks as good or better than any keelboat with proper technique. Upwind in light air with an upwind screacher, our tacking angles are similar to a boat like the J-111. With our smaller Solent sized jib, our tacking angles open up to 100-105 degrees dependent on sea state. 

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IMS was this way 20 years ago.  Here's the issues they faced:

1) Wind isn't always consistent throughout the course (esp in a distance race), and as faster boats separate from slower boats the differences can be significant.

2) It's hard to determine the wind strength throughout the course.  Some regattas tried to collect data from the boats on the water but that just turned into a math thesis to get results and not everybody has calibrated instruments.

3) Doesn't take into account water current effects (which can also vary depending on where you are on the course).

4) The more you try to add data to even the field, the more time it will take to compile the data and sometimes you have to wait a day or more to get the final results.

If you want to do this I think you have to settle on one wind strength to use, don't complicate it.

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15 minutes ago, sam_crocker said:

IMS was this way 20 years ago.  Here's the issues they faced:

1) Wind isn't always consistent throughout the course (esp in a distance race), and as faster boats separate from slower boats the differences can be significant.

2) It's hard to determine the wind strength throughout the course.  Some regattas tried to collect data from the boats on the water but that just turned into a math thesis to get results and not everybody has calibrated instruments.

3) Doesn't take into account water current effects (which can also vary depending on where you are on the course).

4) The more you try to add data to even the field, the more time it will take to compile the data and sometimes you have to wait a day or more to get the final results.

If you want to do this I think you have to settle on one wind strength to use, don't complicate it.

I agree Sam. You have the issues above no matter what types of boats are racing. I would have to believe the PRO is given the authority to establish the average wind strength for a given race and his/her word is final. 

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1 hour ago, AClass USA 230 said:

Trimarans do not foil. Make sure you are not confusing a trimaran with a foiling catamaran. Small beach or foiling catamarans are not pertinent to this discussion.

Corsair trimarans are very, very similar to a planing sportboat (i.e. think Melges 24/32 in comparison) with the primary difference being our righting moment comes from the floats rather than a bulb keel on a fin. At a certain hull speed, the center hull will plane just as a sport boat hull does after it exceeds hull speed.

We did a 100 mile distance race from Gulfport, MS to Pensacola, FL several years ago. The start was a mass start and the conditions were 5-12 knots for the entire race. We pretty much sailed boat for boat with a J-111 helmed by Olympic silver medalist Johnny Lovell for the entire race (36’ monohull sportboat versus 24’ trimaran). We beat them by about 10 minutes elapsed, they corrected out on us by 12 seconds. This turned a lot of heads at the time that the boats could race against each other. I will say that if the breeze would have been 10-15 knots, we would probably would have beaten the J-111 easily, thus multi-rating based on the performance of the boat in different wind conditions would be applicable. 

Our boat pretty much sails the same downwind angles as the sportboats (90-100 degrees apparent). It tacks as good or better than any keelboat with proper technique. Upwind in light air with an upwind screacher, our tacking angles are similar to a boat like the J-111. With our smaller Solent sized jib, our tacking angles open up to 100-105 degrees dependent on sea state. 

Foiling is included for completeness... you can buy them now, and the contrast in recent AC between displacement and foiling modes highlights the difficulty. 

In 15 kts TWS, at 90 deg TWA, Lioness would be powered up and going 7.5 kts in a roar of quarter wave that would swamp a J-24. 

at 60deg TWA, or 120 TWA that probably drops to 6.5 kts. At 25 kts we are still going about 8 max. 

you guys would probably be going triple to 4x that. 

 

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2 hours ago, LionessRacing said:

Foiling is included for completeness... you can buy them now, and the contrast in recent AC between displacement and foiling modes highlights the difficulty. 

In 15 kts TWS, at 90 deg TWA, Lioness would be powered up and going 7.5 kts in a roar of quarter wave that would swamp a J-24. 

at 60deg TWA, or 120 TWA that probably drops to 6.5 kts. At 25 kts we are still going about 8 max. 

you guys would probably be going triple to 4x that. 

 

I should have said Corsair trimarans (all models) do not foil. Again, they are very similar to a planing sportboat and could be treated as such with appropriate ratings. I know also that some PHRF fleets would split performance boats that can plane from strictly displacement boats and the Corsairs could fit into that kind of scenario. Yacht racing at all levels is currently a stagnant sport at best. We need to be more open to how to make it more inclusive for more boats and type of boats to participate.

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5 minutes ago, AClass USA 230 said:

I should have said Corsair trimarans (all models) do not foil. Again, they are very similar to a planing sportboat and could be treated as such with appropriate ratings. I know also that some PHRF fleets would split performance boats that can plane from strictly displacement boats and the Corsairs could fit into that kind of scenario. Yacht racing at all levels is currently a stagnant sport at best. We need to be more open to how to make it more inclusive for more boats and type of boats to participate.

Bob,

I agree that we need to include as many boats as possible, but, even rating Corsair trimarans vs Corsair trimarans is difficult.  We use PHRF TOT at AYC and the ratings of the regular racers range from -45 to 48.  Even using TOT, the slow boats have a strong advantage in light winds and the fast boats have a strong advantage in heavy winds.  If the wind is steady and in the 10 to 15 kt range, the ratings seem to work pretty well.  We tried to rate beach cats with trimarans for a couple of years, but we couldn't come up with ratings that worked.

I wish I knew the solution.  At least among the trimarans, we have a somewhat disinterested 3rd party (TOMA),doing the ratings...

 

 

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4 hours ago, AClass USA 230 said:

I agree Sam. You have the issues above no matter what types of boats are racing. I would have to believe the PRO is given the authority to establish the average wind strength for a given race and his/her word is final. 

Yeah, I agree.  The issue comes down to IMS seeming so scientific that people expect it to be perfect and want all the data to be perfect too (cue whinging when it's not).  I figure most of the complainers just want an excuse for why they finished closer to the bottom than the top.

Re: item 3, at BBS around the turn of the century IMS got a lot of heat for having skewed results due to current.  That eventually resulted in an attempt at using IRC the next year, which because it's a TOT system supposedly is less vulnerable to current effects. 

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FWIW, the new PHRF ratings that the GYA will be using are generated by ORReZ's VPP, and will have 2 wind ranges and 2 courses to choose from. As I understand it, the results will be very similar if not the same as ORReZ, they just using a whole "phrf" number as the coefficient instead the decimal coefficient ORReZ uses. That and it will be TOD instead of TOT so it should be easier for racers to figure out how they finished. 

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10 hours ago, AClass USA 230 said:

We pretty much sailed boat for boat with a J-111 helmed by Olympic silver medalist Johnny Lovell for the entire race (36’ monohull sportboat versus 24’ trimaran). We beat them by about 10 minutes elapsed, they corrected out on us by 12 seconds.

No offense but if an olympic medalist is only beating you by 12 sec, doesn’t this suggest that rating a multi vs a displacement boat doesn’t work well?

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20 hours ago, LionessRacing said:

PHRF and other ratings with VPP's...

this makes it sound like PHRF and VPP-based rating systems are equivalent, when they clearly are not. Your statement makes it seem as if VPP-based systems are no better than subjective PHRF ratings.

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12 hours ago, Controversial_posts said:

No offense but if an olympic medalist is only beating you by 12 sec, doesn’t this suggest that rating a multi vs a displacement boat doesn’t work well?

No offense taken but I've competed against said Olympic medalist since he was a teenager and while I don't have an Olympic medal in my resume, I have podium finishes and wins at class championships that range from Laser, Snipe, VX One, Rhodes 19 (!), Corsair, and of course my favorite A-Class catamaran to name a few. I believe the battle we had in that long distance race showed the ratings we had were accurate for the conditions. Said Olympic medalist even commented on that to me after the race was over.

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AClass,

just heard from ORA that they are currently rating a sprint 750 under EZ to race in his local fleet against monohulls. So.. it's definitely possible.

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4 hours ago, ryley said:

this makes it sound like PHRF and VPP-based rating systems are equivalent, when they clearly are not. Your statement makes it seem as if VPP-based systems are no better than subjective PHRF ratings.

Actually while they are based on totally different methods, both have the premise of predicting performance at some point or range of conditions. As such they are similar in intent, and the differences in actuality vs conditions are widely debated elsewhere. Trying to use any rating to compare very different types and/or sizes of vessel in a variety of conditions is a challenge. With an absolutely accurate VPP, you could presumably do it if you had absolutely accurate conditions data. With good observational data PHRF gets reasonably accurate over the years, as the subjectivity gets ground away

 

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2 minutes ago, LionessRacing said:

Trying to use any rating to compare very different types and/or sizes of vessel in a variety of conditions is a challenge.

we have had excellent results combining diverse boats under orr-ez, for instance a tricked-out J35, Arcona 430, Class 40, Quest 33, and Frers 33 as well as others on an overnight distance race. the results were remarkably close especially among the top 3 boats. VPP-based ratings give you opportunities for scoring that is as simple or as sophisticated as your fleet can absorb. Do you really think that using PHRF for a race from Newport to Bermuda makes sense or is fair?

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1 hour ago, ryley said:

we have had excellent results combining diverse boats under orr-ez, for instance a tricked-out J35, Arcona 430, Class 40, Quest 33, and Frers 33 as well as others on an overnight distance race. the results were remarkably close especially among the top 3 boats. VPP-based ratings give you opportunities for scoring that is as simple or as sophisticated as your fleet can absorb. Do you really think that using PHRF for a race from Newport to Bermuda makes sense or is fair?

What's the spread in TCF on all of those ? 

ANY rating system can work in narrow ranges with similar hulls, rigs, SA/D; your example is therefore meaningless (See my first post above) 

  • Where are the heavy displacement family cruisers or IOR or CCA designs ?
  • How about multi-hulls as was part of the OP? 
  • How do you rate a boat that foils at 20 kts TWS but not at 15? 
  • What about "cat ketches" ? 
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A few years ago there was some theoretical dicussions about a long offhsore race and how to handle varying boats and wind conditions (eg: boats could be started a day or three apart and thus the wind gods were very different for each boat throughout the course).

In the theoretical world, it was considered to rate each boat in the weather in which they race, on a spot basis, and then, euphemestically using calcuclus, add up all these slices for each boat, and then compare each boat versus their 'spot' theorectical best speed. It was surmised that  boats would gather wind data through the race via packages such as Expedition, turn in their logs upon finish, and with a little computer crunching, their theoretical 'actual vs polar targets' for that boat's specific race conditions could then be determined - and then  a ranking could be completed for the podium!!

 

Obviously, not likely to happen anytime soon, but theoretically feasible - and really shows how multiple ratings for multiple conidtions could actually work if taken to the nth degree (and hey, some day this will probably be a reality given the advance of on course trackers and real time weather capture!!)

Not sure how to make perfect handicaps given displacement vs planing vs foiling vs varying wind conditions in the near term. I guess we are really stuck with horses-for-courses, at least for a while!!!

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Lioness,

Boat Type                      SA/D U    SA/D D

Columbia 30-2              25.2          56.8
J/35                                27.3           49.1
Quest 33                        22.0          47.2                               
Arcona 430                   24.9           41.2
Class 40                         34.7          67.5

Guess which boat won that light air, overnight, 50 mile race? spoiler, it wasn't the class 40.

Also, did you miss the post where I said that ORA is right now rating a sprint 850 to race against monohulls? What about cat ketches? they can get ez ratings too. The vpp is pretty good at picking out the optimal upwind angles. Real-life case: my Freedom 45's polars never go below 45 degrees true beating, where my columbia goes as low as 37. If you don't think that the boats' ratings across multiple conditions and course types don't reflect these differences, then you clearly don't understand how ORR/ez/ORC or any other VPP program work. You don't seem to know that they rate boats with water ballast, swing keels, trapezes, and a host of other features that PHRF either ignores or penalizes in arbitrary, unreasonable ways. I'll bet you didn't know that there is an ORA pilot program to rate a foiling boat as well. Yes, it's experimental, but it's happening. What do you think PHRF would say? For a number of years in NE, all the maxis had the same PHRF rating: -69.

You can remain a PHRF luddite if you want, plenty will. But VPP rating systems are getting more sophisticated and informed by the day, and the technology to be able to utilize those ratings fairly is also advancing. Perfection is the enemy of the good, and none of these systems is remotely attempting to be perfect. but they ARE good, and getting better.

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4 hours ago, ryley said:

You can remain a PHRF luddite if you want, plenty will. But VPP rating systems are getting more sophisticated and informed by the day, and the technology to be able to utilize those ratings fairly is also advancing. Perfection is the enemy of the good, and none of these systems is remotely attempting to be perfect. but they ARE good, and getting better.

Except that ORR-EZ will use completely fake numbers, when it doesn’t have the actual offset files for the boat. So the rater basically takes another hull where you do have the offset,  and then tweaks some constants, and declares it scientifically valid. 
 

oh yeah, and with no measurements of sails, foils, or weights... there’s a huge fudge factor across the fleet.

It’s fine and good, but not clear that it’s any more scientific than PHRF. 

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13 minutes ago, Controversial_posts said:

Except that ORR-EZ will use completely fake numbers, when it doesn’t have the actual offset files for the boat. So the rater basically takes another hull where you do have the offset,  and then tweaks some constants, and declares it scientifically valid. 
 

oh yeah, and with no measurements of sails, foils, or weights... there’s a huge fudge factor across the fleet.

It’s fine and good, but not clear that it’s any more scientific than PHRF. 

This is wrong.  The offsets are very closely approximated using a hull manipulation tool that Jim Teeters at ORA has developed.  The primary dimensions are matched (L, LWL, B, depth, draft, displ.).  Hull shape is very close to actual.  Both ORR and ORC VPPs make predictions based on parametrics of the hull, not a hydrodynamic simulation.  So of you get the overall dimensions very close, and the shape is very close by trained eye using the lines, you are within a couple percent or less.  Trimming your sails poorly will have a bigger error.

 

Maybe check your facts before you spout nonsense.

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14 minutes ago, bgytr said:

This is wrong.  The offsets are very closely approximated using a hull manipulation tool that Jim Teeters at ORA has developed.  The primary dimensions are matched (L, LWL, B, depth, draft, displ.)

So you agree, ORR-EZ uses “simulated” offset files, not the actual offsets / 3d models?  What is the validation for this approximation?  If it were a box rule, then primary dimensions might make sense, but I (and others) skeptical are that the VPP is as accurate and valid as ORC using actual hull models.

 

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24 minutes ago, Controversial_posts said:

So you agree, ORR-EZ uses “simulated” offset files, not the actual offsets / 3d models?  What is the validation for this approximation?  If it were a box rule, then primary dimensions might make sense, but I (and others) skeptical are that the VPP is as accurate and valid as ORC using actual hull models.

 

The VPPs originally were derived from parametric hull tank tests.  These bounded the range of hull dimensions, tested multiple hulls and isolated the forces and moments.  Through the years these were confirmed with numerical simulations and enhanced and expanded as computing power grew to greatly enhance and enlarge the accuracy of the vpp application.

Do you know what you are talking about?  I just retired from the David Taylor Model Basin this past December after a full career as a naval architect.  Many hulls were tested there.  I suggest you quit while you're behind.

ORC doesn't use the actual offsets either if the hull has not been digitized.  They have their approximating algorithms for ORC club.

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Well, since I am ahead... being proved right and all...

One thing that really annoys me is how the ORR-EZ likes to talk about how corrected “spreads” are very close, as if that somehow validates the VPP.

How fucking stupid is that?  So a Melges 32 with all new sails, mostly pro crew, dry sailed, running Expedition and nailiing their start SHOULD correct close to Jim’s Beneteau 361, with all his cruising gear on board, bagged out sails, never dived, a blank look on the face when you say “polars”, and a full 3 minutes late to the start?
 

If they’re correcting in ghe same hour that tells you your VPP is crap. 
 

Look, VPP racing is a fine system, but the evangelists just need to admit its just another way of guessing. 

 

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Curious, do the VPPs accurately predict planing? What effect does wave state play? I used to hear about pitching gyradius in the IMS days.Can someone explain?

isn’t part of the “secret” part of ORR the subjective manipulation to offset poor predictions of speed due to bad foil design?

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12 minutes ago, Controversial_posts said:

Well, since I am ahead... being proved right and all...

One thing that really annoys me is how the ORR-EZ likes to talk about how corrected “spreads” are very close, as if that somehow validates the VPP.

How fucking stupid is that?  So a Melges 32 with all new sails, mostly pro crew, dry sailed, running Expedition and nailiing their start SHOULD correct close to Jim’s Beneteau 361, with all his cruising gear on board, bagged out sails, never dived, a blank look on the face when you say “polars”, and a full 3 minutes late to the start?
 

If they’re correcting anywhclose that tells you your VPP is crap. 
 

Look, VPP racing is a fine system, but the evangelists just need to admit its just another way of guessing. 

 

Any handicap system is flawed, mainly due to scoring issues and the dynamics of the conditions, not the vpp itself.  The vpp's are remarkably accurate at predicting static performance for well maintained, prepared, and sailed boats.  

I would guess the majority of folks who've had the unfortunate experience of racing in phrf have seen the boat every season in their fleet that is rated completely out of whack for whatever reason.  At least vpp based rules eliminate that bullshit.

An interesting development in scoring using the vpp for distance point to point racing that has been done on a few trial bases is using optimal routing to predict theoretical elapsed time vs. actual elapsed time.  The boat with the best fraction wins.  That way varied conditions for a wider range of boats can be better captured.  Ie, if the breeze eases up after the fast boats finish, the slower boats still have a chance as their optimal route will catch the changing conditions.

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12 hours ago, Controversial_posts said:

Except that ORR-EZ will use completely fake numbers, when it doesn’t have the actual offset files for the boat. So the rater basically takes another hull where you do have the offset,  and then tweaks some constants, and declares it scientifically valid. 
 

oh yeah, and with no measurements of sails, foils, or weights... there’s a huge fudge factor across the fleet.

It’s fine and good, but not clear that it’s any more scientific than PHRF. 

Let's tackle hulls first. Yes, it's true that ez does a 'build a boat' based on photos, literature, and any other sources of data they can when there isn't a hull file. But they don't do this in a vacuum, and the results of the vpp are checked against existing ratings to make sure that the results seem reasonable. It's still better than PHRF and less expensive than having your hull measured (especially given the lack of official measurers in the US). But the generated hull files are hardly "fake numbers."

Secondly, sails are measured whenever possible, and when they aren't they are assumed to be the largest sail the boat can carry given its rig dimensions, which generally penalizes the boat. There is even a function in the application process to send an email directly to your sailmaker for them to submit the measurements, so.. again wrong. 

As to foils and weights, you're mostly correct - BUT - the VPP isn't currently looking at naca foil sections to my knowledge. Declared weights and brochure weights are always suspect, so whenever possible sister ship weights are used, or a weighted average of the fleet of sister ships is used. 

The great thing is that if you have a dispute about the measurements, the hull shape, or the weight, you have recourse - go spend the money to get measured and those results will be incorporated into the rating, whereas with PHRF you *might* get a +3 or a -6 based on the new data, but if they've already rated a boat like yours, chances are your rating isn't changing. 

Again, perfection is the enemy of the good. And here's the best part about ORR/ez/ORC - as their database of boats gets larger and the number of race results gets bigger, their models get more and more refined, assumptions are refined or rejected, and there is a yearly, measurable, continuous improvement. Nearly every PHRF region has written into their bylaws that they will review yearly races and adjust ratings as necessary, but we all know that's bullshit, but it's understandable that people that are volunteering their time to rate boats don't want to spend the extra time necessary - and probably aren't qualified - to do the type of in-depth analysis necessary to modify observed ratings. Not to mention that PHRF adjustments can appear capricious. For instance, the "recreational" rating in PHRF-NE requires a headsail furler - but allows both above and below-deck furlers! For a rating adjustment that was originally basically a golf handicap for old sails and early furler designs, this is an easy way for someone to game the system. I only know one way to game ORR/ez/ORC and I think ORC and ORA are both closing the loophole.

 

 

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Some interesting ideas in this conversation. 

One thing that jumps out at me is that with PHRF, as long as the rating is in the ballpark, you're likely to have at least some races where the wind-conditions are spot on for your rating. And if it's consistently unfair, you can appeal or protest the rating (though almost no one does this, they'd rather just bitch about it.)

But with ORC and ORR VPP modeling, there's a risk that the model overly emphasizes (or ignores) a particular feature, allowing that "unfairness" to be replicated across wind ranges.  And the best designers are undoubtedly running more sophisticated VPP algorithms on their hull forms to game out a boat that's faster in real life than the VPP can account for. 

 

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22 minutes ago, Salona said:

Some interesting ideas in this conversation. 

One thing that jumps out at me is that with PHRF, as long as the rating is in the ballpark, you're likely to have at least some races where the wind-conditions are spot on for your rating. And if it's consistently unfair, you can appeal or protest the rating (though almost no one does this, they'd rather just bitch about it.)

But with ORC and ORR VPP modeling, there's a risk that the model overly emphasizes (or ignores) a particular feature, allowing that "unfairness" to be replicated across wind ranges.  And the best designers are undoubtedly running more sophisticated VPP algorithms on their hull forms to game out a boat that's faster in real life than the VPP can account for. 

 

There are very few folks who will employ the technical people to game the vpp, although it does happen.  For those handful of folks, they do the vpp a service by exposing weaknesses.  Most of those have already been exploited and closed through the years, and it has become much much harder to fool the vpp than in years past.  Especially since computing power grows exponentially, and simulation can now be done on a desktop vs. some massive computer system.  

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24 minutes ago, bgytr said:

There are very few folks who will employ the technical people to game the vpp, although it does happen. 

If I were buying a brand new boat, I'd be pretty disappointed if the designer wasn't using a proprietary VPP to beat the ORC VPP! 

If you take a look at results from the last ORC Worlds in Croatia, it at least appears that ORC favors some design types over others:

 

 

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59 minutes ago, Salona said:

 

If I were buying a brand new boat, I'd be pretty disappointed if the designer wasn't using a proprietary VPP to beat the ORC VPP! 

If you take a look at results from the last ORC Worlds in Croatia, it at least appears that ORC favors some design types over others:

 

 

That depends on what type of boat you want- you want a rule-beater, or do you want a boat that is a good boat regardless of some rule?

There's a whole lot more sailboats out there that don't actively race than those that do.

There's lots of things that could influence results, and often folks in err immediately look at the rule.  Anecdotal data doesn't help as there's not much fundamentally different between a Swan 42 and a Bene 40.7.   Also bad design is not given a credit in the VPPs as I understand, ie if the keel is too far forward, then you don't get a credit for having to have your rudder cranked over 20 degrees upwind.  So if you got a shitty boat, tough luck.

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