Ratings & Handicap Systems - IRC/PHRF

[ckh]

INFO:

Handicap racing is the generic term used to describe races in which boats (either dinghies or yachts) of different speeds compete against each other and, thorough subsequent mathematical calculation, their true positions in the race attributable to the skill of the crew is determined by negating the physical speed effects of the boats.
These determinations of which crew beat which are calculated by correcting the actual time it took each boat to complete the race by a numerical measure of the boat speed - its handicap.
https://www.sailing.org/classesandequipment/offshore/ratings_and_handicap_systems.php

IRC
IRC is a rating rule to handicap different designs of keelboats allowing them to race together; unlike a performance handicap a rating is not altered between races according to the individual boat’s performance, but is based on the physical measurements of the boat.
https://ircrating.org/irc-certificate/what-is-irc/

PHRF
PHRF handicaps are assigned by individuals or committees associated with specific fleets. Handicaps are assigned to a given production class considering predominant local conditions and the handicapper’s experience in handicapping similar boats. These ratings are based on observed performance and any requisite adjustments generally become evident after 5-10 races have been sailed. Scoring options include Time-on-Distance or Time-on-Time.
https://www.ussailing.org/competition/offshore/phrf/


Additional related discussions:
https://steamcommunity.com/app/552920/discussions/0/1470841715948864538/
https://steamcommunity.com/app/552920/discussions/6/1692669912396793864/

[ckh]

SAILAWAY SIMULATOR BOAT RATINGS- RECALCULATIONS OCTOBER 2019*

IRC & PHRF Handicap



Boat ..............IRC Rating............PHRF

IMOCA60........1.308.......................-60
50PC...............1.151........................8
32OR...............0.971......................112
Mini..................0.930......................142
52Cat...............0.725......................340
38C .................0.650......................443
Rose.................0.643.....................454
Folk .................0.522......................688

*Formula utilized to calculate new handicap rating:
H+(PIxPM)

H=old handicap/rating
PI=Performance Indicator (h-H)
-h=performance handicap (SCT/ET)
-SCT=Average of Corrected Times(CT)
-ET=Elapsed Time(f-ST)
-f=Finished Time
-ST=Start Time
-CT= ETxH
PM=PI Multiplier
-A multiplier of 1.00 was utilized in the calculation.

PHRF Rating Calculated with:
http://phrf-calculator.herokuapp.com/distance

[ckh]

I use a spreadsheet which calculates Corrected times utilizing the handicaps/ratings above.

The spreadsheet was acquired from:
https://www.sailing.org/classesandequipment/offshore/ratings_and_handicap_systems.php
Contact me if you would like to review my modified version.

I use it for Treasure Coast Ocean Racing Association(TCORA) Regattas in Sailaway Simulator as well as for racing in real life.

The handicap/ratings above have been derived from base handicaps; which have been recalculated as additional data have become available.

IMOCA60 (Open 60) base handicap/rating was acquired from:
http://www.phrfne.org/page/handicapping/base_handicaps

Utilizing the PHRF Rating formula above, the IRC rating was calculated.
This rating will continue to be adjusted as new data is compiled.

The KETCH handicap/rating is a work in progress....


THE NEXT SAILAWAY SIMULATOR IRC/PHRF RECALCULATIONS WILL BE CONDUCTED IN MARCH 2020.

[Ubizon]

Originally posted by ckh:

I use a spreadsheet which calculates Corrected times utilizing the handicaps/ratings above.

The spreadsheet was acquired from:
https://www.sailing.org/classesandequipment/offshore/ratings_and_handicap_systems.php
Contact me if you would like to review my modified version.

I use it for Treasure Coast Ocean Racing Association(TCORA) Regattas in Sailaway Simulator as well as for racing in real life.

The handicap/ratings above have been derived from base handicaps; which have been recalculated as additional data have become available.

IMOCA60 (Open 60) base handicap/rating was acquired from:
http://www.phrfne.org/page/handicapping/base_handicaps

Utilizing the PHRF Rating formula above, the IRC rating was calculated.
This rating will continue to be adjusted as new data is compiled.

The KETCH handicap/rating is a work in progress....


THE NEXT SAILAWAY SIMULATOR IRC/PHRF RECALCULATIONS WILL BE CONDUCTED IN MARCH 2019.

I assume you mean March 2020?

[Ubizon]

Otherwise, well done, nice work!

[ckh]

Originally posted by Ubizon:

Otherwise, well done, nice work!

yes of course March 2020!

[Gygory]

Thank you for the hard work!. Can you point to a programme that if I run a race I can compute the time to get results. Did it in old days with, paper, pens and a calculater and dinghies and the like but am a bit old now and used to computers
lol

[ckh]

Gygory,
This link has the spreadsheets I have utilized. I have modified mine slightly, the calculations and results are the same though.

https://www.sailing.org/classesandequipment/offshore/ratings_and_handicap_systems.php

If you want,I can give you a copy of my most recent spread sheet I use with handicap ratings for the boats in sailaway.

It can always be modified to suit your needs.

[ckh]

UPDATE- Ketch IRC Rating & PHRF

SAILAWAY SIMULATOR BOAT RATINGS

IRC & PHRF Handicap



Boat ..............IRC Rating............PHRF

IMOCA60........1.308.......................-60
50PC...............1.151........................8
Ketch*..............1.072........................49
32OR...............0.971......................112
Mini..................0.930......................142
52Cat...............0.725......................340
38C .................0.650......................443
Rose.................0.643.....................454
Folk .................0.522......................688

* The World Sailing Empirical Handicap Scheme for first race(only) handicap was utilized to calculate the rating.
Steps in Calculation:
1)Key boat length as length overall (LOA)
2) Key unit of boat length as either 1(feet) or 2(meters)
3)Key sail size / area from 1 to 5 (1-very small sail area to 5-very big sail area)
4)Key boat weight or displacement from 1 to 5 (1-very heavy to 5-very light)
5) Key hull and keel shape from 1 to 5 (1-old design cruising or work boat to
5-out and out racer)

Note: This form may be used to calculate a yacht's handicap rating for it's first race only.
After the first race the handicap rating should be adjusted as described in the scheme notes.
Additional Ketch races times will allow for refinement of handicap rating.
https://www.sailing.org/classesandequipment/offshore/ratings_and_handicap_systems.php