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Seeking input on PHRF


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Totally understand this Mark

It's just that they are seeking input into the PHRF

And I believe it would be more relevant if they were related, as in short handed boats could race on there SH rating against fully crewed boats on there inshore/offshore rating.

 

At present most sailors and the ISAF agree existing handicap systems aren't fair and are a bone on contention worldwide.

 

They have determine this could be the major reason for falling race entries and wish to correct the situation.

 

They should be all scraped and start using the New VPP ISAF handicap system based on design with designers certificate weight wind etc. during the race and computerized producing a handicap / and or time for the race if sailed at 100 % efficiency . So no matter what size vessel - age - professional - gear - go fast stuff - the vessel that sails their vessel with the highest % efficiency is the handicap winner. This allows older boats to compete fairly against new designs. The fundamental idea is to get more race entries. THEY HAVE THE COMPUTER MODEL

 

 

 

 

Velocity Prediction Program (VPP)

 

It is intention of any rating system to give a boat rating which depends on her characteristics in order to equalize her with other boats of different size and characteristics. Characteristics that are positive for boat speed, like length of the water line or sail area, and those that are negative, like beam, displacement and wetted surface, are the most common influences in any rating system. Establishing which of these characteristics influences boat speed is therefore the problem that has to be resolved. Thanks to the developments in modern science and technology, ORC gives the most accurate solution to this problem, and establishes important principles of boat measurement and calculation of corrected times.

 

The only possible way to rate boat fairly is to tell how fast she can sail in certain wind conditions or to predict her speeds. To do so, ORC has developed with continuous research and update an ORC Velocity Prediction Program (VPP) as mathematical model which calculates boat’s performance from the set of measurements and gives rating which is then applied for race scoring. ORC VPP is calculating boat’s theoretical speeds for various conditions: wind strength of 6, 8, 10, 12, 14, 16 and 20 knots, direction of true wind from the close-hauled to 52, 60, 75, 90, 110, 120, 135, 150 and 180 degrees. VPP program creates a computer simulation of the boat’s performance based on scientific research of boat hulls in hydrodynamic basins, sails in aerodynamic tunnels and measurements taken on real boats as well as computer fluid dynamics (CFD) tools available nowadays.

 

The VPP has a two-part structure comprised of the solution algorithm and the boat model. The solution algorithm must find an equilibrium condition for each point of sailing where the driving force from the sails matches the hull and aerodynamic drag, and the heeling moment from the rig is matched by the righting moment from the hull.

 

VPP calculations take in account additional weight on board for the total crew and sails and equipment on board while racing.

 

OC

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CIORC have largely working with PHRF lately, however they have had discussions about engaging with the multi fleets. YNZ will make an approach to the Multihull YC to see if someone would like to come

The posting above by GUEST is ISAF wording they are promoting it / pushing it [ READ THEIR WORDING ] and the USA have joined the revolution towards it. Quoting Europe is a no argument. The argument is

That's no excuse if their is a better and fairer system.   OC

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Having a read of the news on the proposed PHRF changes (see Scotties link above) I do have to wonder what the rational behind one bit is.

 

Surely a boat that sailed 24.9 nm doesn't suddenly slow or speed up a 100mts later. So one does wonder why drop SH but keep under 25nm and over 25nm instead.

 

Also wouldn't dropping the SH surely lead to some strange distortions and the ability to game the system even more?

 

Example - I sail SH a lot so after a while PHRF would adjust to me sailing slower due to no rail meat. That's fine as long as I stay SH. But say I rock up to the fully crewed Auckland Regatta after a few months of... opps it's PHRF were talking here* :twisted: , after say 2 years of Short handing. In the fleet is X and Y, both only sail fully crewed.  

 

Aren't I now going to have a legend PHRF number to use against X and Y's whose PHRF numbers have been fully adjusted to take into account the 4 fat rum swilling ugly bastards they have had sitting in the gunwale?

 

* - Yes I have noticed the update in review frequencies. That is arguably one of it's biggest failings, it's to slow moving, so it's great to see that happening.

 

 

As a sometimes harsh critic of PHRF I do like the direction the team are currently pushing it. I am liking your work to date, Thank you.

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At present most sailors and the ISAF agree existing handicap systems aren't fair and are a bone on contention worldwide.

 

They have determine this could be the major reason for falling race entries and wish to correct the situation.

 

They should be all scraped and start using the New VPP ISAF handicap system based on design with designers certificate weight wind etc. during the race and computerized producing a handicap / and or time for the race if sailed at 100 % efficiency . So no matter what size vessel - age - professional - gear - go fast stuff - the vessel that sails their vessel with the highest % efficiency is the handicap winner. This allows older boats to compete fairly against new designs. The fundamental idea is to get more race entries. THEY HAVE THE COMPUTER MODEL

 

 

 

 

Velocity Prediction Program (VPP)

 

It is intention of any rating system to give a boat rating which depends on her characteristics in order to equalize her with other boats of different size and characteristics. Characteristics that are positive for boat speed, like length of the water line or sail area, and those that are negative, like beam, displacement and wetted surface, are the most common influences in any rating system. Establishing which of these characteristics influences boat speed is therefore the problem that has to be resolved. Thanks to the developments in modern science and technology, ORC gives the most accurate solution to this problem, and establishes important principles of boat measurement and calculation of corrected times.

 

The only possible way to rate boat fairly is to tell how fast she can sail in certain wind conditions or to predict her speeds. To do so, ORC has developed with continuous research and update an ORC Velocity Prediction Program (VPP) as mathematical model which calculates boat’s performance from the set of measurements and gives rating which is then applied for race scoring. ORC VPP is calculating boat’s theoretical speeds for various conditions: wind strength of 6, 8, 10, 12, 14, 16 and 20 knots, direction of true wind from the close-hauled to 52, 60, 75, 90, 110, 120, 135, 150 and 180 degrees. VPP program creates a computer simulation of the boat’s performance based on scientific research of boat hulls in hydrodynamic basins, sails in aerodynamic tunnels and measurements taken on real boats as well as computer fluid dynamics (CFD) tools available nowadays.

 

The VPP has a two-part structure comprised of the solution algorithm and the boat model. The solution algorithm must find an equilibrium condition for each point of sailing where the driving force from the sails matches the hull and aerodynamic drag, and the heeling moment from the rig is matched by the righting moment from the hull.

 

VPP calculations take in account additional weight on board for the total crew and sails and equipment on board while racing.

 

OC

YNZ WHERE IS THE REPY.

 

This system is becoming a revolution for overseas clubs and answers the falling numbers issues entering races and local yacht clubs and inter yacht numbers races.

 

A reply would have been expected and the system adopted / encouraged / recommended as the ISAF are recommending it and promoting it and they are above YNZ.

 

OC

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Rehabilitated

 

Think you will find IRC is the more popular of the measurement handicaps in English speaking countries, ORC more popular in Europe excluding France and then of course there's ORR and HPR in the United States.

 

Whilst patterns of use change slightly from year to year, neither IRC nor ORC are becoming dominant over the other and each have similar levels of active certificates.

 

IRC is the preferred measurement handicap in New Zealand, primarily because it's probably the handicap that will be used if a New Zealand boat races offshore, eg, to do a Sydney Hobart, Hamilton Island or Fastnet.

 

That said, both are available in New Zealand, costs from memory are similar.  Don't think ISAF push any one handicap over another, they pretty much leave national authorities to decide what's appropriate for themselves, which is how it should be.

 

Whether either would be appropriate for club local racing is pretty debatable, myself I would say that forcing clubs to use either for their local races with the costs that it would entail would be one of the quicker ways of killing off that level of racing.

 

At a slightly more serious level of racing, coastal type stuff, there is interest in some areas in further encouraging use of measurement based handicapping.

 

Whether that comes to pass or not is really the choice of boat owners.  PHRF is currently the default for a variety of reasons, it'd be good to see more of IRC, whether it's in anyones interests to complicate things by adding in a third system is pretty debatable. 

 

Both IRC and ORC have strengths and weaknesses, myself I'm to be convinced that ORC is so much better than IRC that the latter should be ditched in favour of it.

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why is it when results are worked out  in any division where it races with yachts that are rated IRC and have a PHRF handicap

A boat can win on IRC and get a bad result in PHRF yet another boat can win on PHRF and get a bad result in IRC in the same race 

surely  the IRC and PHRF should be similar  

Another problem with PHRF is that a yacht that has not raced for a while can come out pick a regatta or a long off shore race and win or get  well placed,  which has  happened in the passed, surely this is unfair to yachts that race regularly, this is not the owners fault, but PHRF rules currently allow this.

To help over come this maybe a yacht should have raced at least 5 races before any regatta or long offshore race so its PHRF can be adjusted if needed 

otherwise you have yacht owners who can pick races/regattas  when  they know they have a chance to win

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LA,

 

From this season, a boat which has no race history from the prior two seasons is allocated a handicap which is typically quite challenging.  That does depend on the ability of the handicapping group to judge a boats potential of course.

 

I can assure you this is not universally popular, people are not as a rule happy if their handicap jumps up a serious chunk and can be quite vociferous in their arguments on the lines of "why did my handicap go up when I haven't done any races?".

 

It is an area which requires a policy in order to be consistent though, it's published and it is what it is, and yes, part of the reason is to try and prevent the circumstance you've outlined from occurring.

 

What can't be prevented under any performance influenced handicap is the area of sandbagging.  The committee has tightened up the range it will allow a design to fall within this season and one benefit of doing this is to limit the advantage that can be gained.  Doesn't stop it, only limit it, objectively policing this area is almost impossible.  As is stated and is the case in other areas of yacht racing, the integrity of the system does depend on the integrity of people racing.

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