Do you understand IRC ratings?

[Guest]

My boat has now been issued with an IRC rating (race handicap) and I simply want to find out other boats with a similar TCC nummber to 0.855

... I posted this (racing) question here because the racing forum seems to be dying ...

 

[Jeremy_W]

IRC ratings

Only three people ever understood the IRC rating system. One went mad; one forgot; and one died - or was that the Schleswig-Holstein question? The only IRC rating I have embedded in my memory is 0.940 for a Sigma 33. If that 0.855 rating is with spinnaker I reckon you've done OK.

But the first rule of handicap racing is "never admit your rating is fair". Many happy hours can be spent explaining away appalling race results by "that maniac in the Lymington Rating Office who hates VdS designs and biased the rule against them"!

 

[Guest]

0.855 with a spinnaker

It is rotten luck that they have given me such a rating, after all I only have on spinnaker and it's over ten years old. My sailmaker, Jeckells, was stunned to hear I'm still using a genoa made in 1992.

I would have though 0.700 was much fairer.

By way of explanation for those not familiar with the IRC TCC (Time Corrected C?) is that each 0.001 difference equates to approx 3.6 seconds per hour.

 

[jamesjermain]

Re: IRC ratings

Humperdink,
Looking in my AZAB 99 file, I came across the following ratings (by now most of them will be a point or two lower).

Elizabethan 30 844, Sadler 34 926, X-312 928, Rival 34 848 and 866, Rival 32 836, Contessa 32 887, Scanmar 33 913, Hallberg Rassy 31 910, S&S 34 890.

Hope that gives you some food for thought

JJ

 

[AndrewB]

Does ANYONE understand IRC ratings?

The point is that the system is secret, though I've seen attempts to unpick it from the ratings given.

Most people I race with generally consider the IRC works well with modern cruiser-racers. But there are some real sore points with the older boats. There was someone on YW a while back, complaining the IRC rating for his aging Westerly 33 put him ahead of X-332's. In our club fleet we have one boat built 50 years ago to an unusual design with a phenomenally low rating. Despite always coming in last he wins every race by 20 mins or more on corrected time. People said that was down to skill - until one of his crew took the yacht out for a couple of races and did exactly the same. Such inconsistencies spoil competition, and people lose interest.

 

[bedouin]

I think the whole point is that you are not supposed to understand them. They are deliberately kept secret and updated often to stop people designing boats to take advantage of the handicap rules.

As I've said elsewhere - it is impossible to devise a simple system that can accurately handicap a 60s/70s design against a modern one since they have different strengths and weaknesses.

All other things being equal you should expect to do very well in heavier weather and when close hauled, but lose out badly in lighter airs and when running or broad-reaching.

 

[DavidTocher]

Re: IRC ratings

Is the AZAB file available somewhere? It's very difficult to find this info. It would be useful if magazine boat reviews gave a handicap figure. The A to Z series could include this with the other statistics

David

 

[kdf]

Re: 0.855 with a spinnaker

with IRC the age of your sails doesn't matter. Its the size of the boat, luff length, sail area (Get your sailed measured as they shrink - don't use measurements from sailmakers), its weight (yes do have it weighed) etc.

 

[bedouin]

Re: IRC ratings

Don't know about AZAB - but last year's RORC figures are available from www.rorc.org (the season cumulative results has the boat type on I believe).

There have been changes to the rule since last year, but I don't know what difference that will make to the figures

 

[Guest]

It\'s all just a bit of fun

This Summer will be my first ever boat race, so I will be very pleased to place anywhere except at the bottom. It's a cruise with a party at each end ... that's why I chose the race I did, that and it just neatly co-incided with my intended cruising ground at the exact time of year I was going to go for my Summer sail.

I'm not really moaning about my rating!

 

[kdf]

Re: It\'s all just a bit of fun

Sounds like fun. You think your rating is bad - mine is 1.084.

 

[Guest]

Ouch!

What is it? A teflon coated keel with a sail?

 

[bedouin]

Re: That\'s not ouch

Ouch is a yacht like 'Stealth'. With a TCF of about 1.7, you could take almost twice as long and still beat her on TCF!

 

[Guest]

Re: It\'s all just a bit of fun

The IRC formula assumes equal amount of beating, reaching and running in medium winds. Therefore unless sailing (small) triangles, there will always be an element of "the course did not suit" or " the wind was wrong" ... makes for discussions in the bar afterwards.