IoR hulls versus modern IRC derived hulls

[Judders]

Impalas weren't designed to rate under IOR...

Scarlet Oyster is a Lightwave 48 - Carl Schumacher designed downwind flyer not designed to IOR constraints. IIRC Old Mother Gun is a lovely one off Humphreys also with no IOR constraints. Are the others not a Dehler 38 and Laser 28? If so again none IOR designs!

Fair observations gents, but in the context of the orgininal thread I was thinking more IOR derived as against IRC derived than specifically IOR boats. The thread grew out of another thread about hull shapes more than a specific rule.

Flaming's observation was about Sigmas as an IOR derived hull shape. The Dehler and the Impala are of an IOR derived shape even if they were not designed to be IOR boats. Similarly now, the Benny 40.7 or J109 (amongst others) were built as one designs but are of what might broadly be termed the IRC era.

 

[Judders]

Only OD game in the Solent at this size is the J109 though. Great boat, but not for everyone.

Sigma 38? The Impala fleet is growing steadilly too.

The argument was that IOR derived hulls are faster upwind that IRC hulls. Which has not been my experience.

I'm not sure that it was necessarilly faster, but more comfortable, though I maintain some IOR boats are quicker as a result. Where the more modern boats win out is their acceleration. I think if you have a long race with a long fetch then the Swan/Sigma 38 ethos wins out still.

But all the anecdotal evidence comes down, rather reassuringly, to it being as much to do with how well they're sailed.

 

[Twister_Ken]

Fair observations gents, but in the context of the orgininal thread I was thinking more IOR derived as against IRC derived than specifically IOR boats. The thread grew out of another thread about hull shapes more than a specific rule.

Flaming's observation was about Sigmas as an IOR derived hull shape. The Dehler and the Impala are of an IOR derived shape even if they were not designed to be IOR boats. Similarly now, the Benny 40.7 or J109 (amongst others) were built as one designs but are of what might broadly be termed the IRC era.

I think David Thomas would resent the implication that the IOR came anywhere near the Impala (or, for the that matter, the Sigma 33). To me, they both look like boats that stem from the Sonata philosophy of sweet lines that put a premium on easy water flow, and pay not a whit of homage to IOR measurement stations.

 

[flaming]

I'm not sure that it was necessarilly faster, but more comfortable, though I maintain some IOR boats are quicker as a result. Where the more modern boats win out is their acceleration. I think if you have a long race with a long fetch then the Swan/Sigma 38 ethos wins out still.

From your OP

I can equally point to the way in which modern Bendytoy 40.7s and First 40s are murdered upwind by late IOR designs.

Which, as I say, has not been my experience.

The comfort thing is probably true though - especially if driven like an IOR design in a rather passive way, rather than actively like they should be. I rather suspect that the reason that IOR designs do so well ofshore in JOG, and to a lesser extent RORC, is threefold. Firstly there is more reaching - which is less disadvantageous for the older boats, secondly the older boats are easier to sail upwind to their potential in the rough stuff and finally the owners have probably had them longer and found out all their tricks!

As to going back to racing the Sigma 38..... I had fun sailing Sigmas, but there is a reason I stopped sailing them.

 

[Judders]

I think David Thomas would resent the implication that the IOR came anywhere near the Impala (or, for the that matter, the Sigma 33).

I shall ask him, or Peter Poland the next chance I get.

The Sonata was built to the 8th Ton measurement which became the Mini-tonner. Given that the Impala is fundemnetally the same shape, I think it's inescapable that the rule had an influence, however as I've said, I'm talking of hull shapes of the era rather than the rule, FWIW.

 

[LouisBrowne]

One can't really talk of IOR yachts as if they were a completely uniform type.

There are the early (1970s) IOR boats like the Sparkman and Stephens Swans with bullet-proof masthead rigs and huge ballast ratio and then there are the late (1990s) IOR boats with spindly rigs and hardly any ballast below the waterline.

The early ones will tramp along to windward for days in a gale with no one hiking whereas the later ones relied very much on the crews' hiking efforts to keep them on track in a light breeze.

In the context of cruising, an early IOR boat would make a very decent cruiser if you don't mind tacking an enormous genoa whereas a late IOR boat would be the worse possible cruising yacht.