29 August 2019

The end of the IOR

I recently came across an article penned by well-known yacht designer Julian Everitt and which had been shared to the One Ton Class Facebook page. Julian has been kind enough to allow me to publish his insightful and thought-provoking article here (to which I've added a few images):

A while back David Macfarlane posed the question: “Why did the IOR die?” The answer is surprisingly simple and has little to do with economic downturns, crazy, escalating costs or the perception that the boats were unseaworthy and slow.
 Australia's Ragamuffin during the last Admiral's Cup under IOR in 1993, not long before the eventual demise of the IOR altogether 
The very people, the members of the International Technical Committee (ITC), who were tasked to protect and develop the rule for the benefit of the owners signed the death warrant some six years before the beast was finally deemed extinct. It wasn’t a deliberate act, by any means, it was just kind of allowed to happen as interests grew in the development of a new ‘super’ rule that would cure all the ‘ills’ of offshore handicapping. It was called IMS. The International Measurement System.

IMS was very much an American based initiative formulated by a burgeoning interest in the power of computers as envisioned by ‘idealists’ at the Massachusetts Institute of Technology (MIT). This belief in a ‘perfect’ system filtered into the ITC who then increasingly believed that IMS could replace IOR as THE rule for Grand Prix Offshore Racing. At a stroke IMS was perceived as a handicapping system that would allow the return of ‘wholesome’ cruiser racers to the Grand Prix level.

ILC40s, as a level-rating derivative of the IMS rule, seen here competing in the 1995 Admiral's Cup
The 1976 French cat rigged Mini Tonner L'Effraie
And so the scene was set for a showdown between the two rules. Funnily enough however, this ‘conflict’ largely took place behind closed doors - the closed doors of the ITC. This erstwhile Group of designers and boffins had done a reasonable job of helping to develop the original, Olin Stephens/Dick Carter created Mk 1 IOR, into an ever more complex Mk III IOR. They had dealt with the slings and arrows of ‘cat’ rigs, unballasted daggerboards, extreme overhangs, bumps, chines and many other rule dodgers thrown at it by a vast army of new, young designers. The rule really was the ultimate mathematical, but organic and holistic challenge imaginable and so it required a lot of policing and an awful lot of tweaking.
The Farr One Ton centreboarder, Jenny H, 1977
At the annual ITC meeting always held in November and euphemistically called The November Meetings informal submissions were invited from the ‘floor’ for what would eventually become IOR Mk IV. But the minds of the powers that be were elsewhere. Despite impassioned pleas from designers including Tony Castro, Geoff Stagg, representing Bruce Farr, the Dubois office, myself and several owners to use IOR as the ‘baseline’ for producing more user friendly designs, the ITC elected to promote IMS as the rule for the future. Gary Mull, chairman of the ITC at this time, seemed to be heavily influenced by a growing love affair from American designers, like Dave Pedrick, Bill Tripp and the ‘scientist’ Jerry Milgram, with IMS. Together they envisioned a new breed of fair hulled, moderate designs, with great stability, proper cockpits and fitted out interiors.

The IOR Mk IV, proposed from the audience at the 1988 November meetings promulgated similar outcomes, but utilising the proven and robust linear formulas of IOR rather than the largely unknown reliance on unproven Velocity Predictions inherent in the IMS formula.

Turkish Delight trying to stay on her feet during the 1987 Irish Admiral's Cup trials
In the proposed revisions to IOR, stability would be unmeasured getting rid, at a stoke, of the dreaded Centre of Gravity Factor - a measurement fraught with inaccuracies and held largely responsible for producing unstable boats and ones overly dependent on crew weight on the rail. CGF was also directly responsible for such undesirable idiosyncrasies as beam waterline bumps.

Gone too would be the ubiquitous 150 percent overlap on headsails which gave unrated sail area. This change would have opened the door to the development of non-overlap rigs.

Victory (left), Hitchhiker and Pinta sporting their big no.1 genoas during the first race of the 1981 Admiral's Cup 
The accursed creases and distortions around the aft girth measurements was to be addressed also. One simple suggestion was to rule out any form of reverse inflection in the aft profile. The days of the bustle were virtually over anyway and of course all of our proposed rule changes could be easily ‘grandfathered’ to prevent the existing fleet suffering too much. In reality small changes to the aft girth stations and most particularly the girth differences between inner and outer girth stations would have produced fuller, wider and fairer sterns in short order, while maintains an element of choice. Choice being a factor missing from today’s rules.

While the outcomes of such changes cannot ever be accurately predicted, cause and effect is highly influential in a formula like IOR. The simple removal of the penalty on stability would have quickly allowed designers to create lighter boats as stability could have been found in low CG keels rather than hull form and brute overall weight. In turn lighter and more powerful boats would have pointed the way to fuller sterns.

Gunboat Rangiriri - one of the new breed of Farr-designed light displacement centreboarders of 1977, showing the relatively clean lines that were possible before the ITC forced an increase in displacement
But the ITC very systematically destroyed these arguments as unworkable and felt IMS was a much more effective way of achieving the same outcomes. In fairness to the ITC a number of designers, including Rob Humphries - a member of the ITC board at the time - had IMS designs out racing that did showcase the rule rather well. But this was to be a short lived moment.

And so the ITC policy was set at that fateful November meeting in 1988. The two rules would run in parallel while the anomalies inherent in the VPP-driven IMS were sorted out and a new era of dual purpose offshore racers would begin.

Work would continue on the development of IOR, but with none of the suggested fundamental changes implemented. A Mk IV Rule was duly drafted, but few in authority had any real enthusiasm for it. As far as they were concerned IOR was dying and IMS was the new kid on the block to be nurtured.

The Whitbread Maxi ketch Steinlager 2 
In an earlier attempt by the ITC to be more inclusive of heavier, more cruising orientated boats an IOR MK IIIA was introduced, but this backfired spectacularly when Bruce Farr, in particular, exploited the carelessly drafted rule by producing the heavier, but much longer Steinlager 2 Whitbread Maxi in 1989. This amazing own goal of a rule amendment created by the ITC finally allowed the creation of the all conquering inshore Maxi Matador. Far from allowing the development of heavier, more fitted out boats, the Mk IIIA rule simply promoted heavier stripped out boats which in the case of the Maxi’s allowed them to effectively gain 3ft, or so, of unmeasured length. This was one of many misdirections the ITC took in trying to ‘protect’ the rule and it had a seriously deleterious effect on owner confidence.
Matador 2, the biggest and fastest of the IOR Maxis 
But back to the ITC meetings of November 1988. I remember it like yesterday, Geoff Stagg’s final reaction to the ITC intragency. “We don’t really care what you do. Just give us any rule and we’ll go off and design winners for it”.

Gaucho (above and below)
And that is precisely what happened. Within two years Farr had produced the ultimate Grand Prix IMS boat in the form of the 43ft Gaucho. But it wasn’t the beginning of the new era predicted by the rule makers of elegance and internal comfort. Gaucho signalled a very different future. Her overhangs were very short, freeboard was high, the sheer line straight and the interior just as stripped as an IOR boat except for the introduction of a door on the ‘head’ compartment. Other required features like a galley and saloon table were treated with token gestures expensively built in carbon. But much more significantly, in order for velocity predictions to work ‘accurately’, actual stability had to be measured. It wasn’t long before lead was being replaced by wood at the bottom of keels. Not exactly the promised land of wholesome cruiser racers envisioned by the rule makers.

But while IMS continued to be promoted as the solution to ‘fair’ global offshore yacht racing IOR struggled on, shouldering virtually all of the blame for declining racing fleets.


I remember talking to Olin (Stephens) about it all. He was very sanguine - perhaps even a little surprised by the way IOR had developed, but ever the enthusiast for a mathematical solution he liked the theories behind IMS and perhaps felt that the apparent shortcomings in the IOR could be addressed more effectively by the overarching qualities of IMS. It was a mathematically-based theory that wasn’t born out in practice.

With the advantage of a 21st century perspective and taking into account yacht racing developments since the death of IOR in 1994, would keeping IOR been better for the sport as a whole? In terms of continuity and preventing the explosion of multiple, fleet sapping alternative classes, it would assuredly have been beneficial. But it did need a major shot in the arm at the end of the 1980s to reassure an ever more cynical owner base that their worries were being addressed.

Cookson's High 5 followed the Gaucho theme and was dominant in the 2000 Kenwood Cup 
In the rarefied atmosphere of Whitbread sponsored global racing, Bruce Farr, once again, showed the way. As IOR lay on its deathbed - an outcome accelerated by clumsy attempts to update events like the Admiral’s Cup with the proposed introduction of one designs and IMS handicapping - Farr, in tandem with the foresight of the Whitbread race committee who allowed asymmetric spinnakers to be flown, discarded the ‘heavy’ design route he had produced with Steinlager 2 and produced a new Maxi design that was some 7,500kgs lighter. This much lighter design was a great deal quicker around the world and potentially showed a new beginning for lightweight IOR racers. Sadly, however, these three Farr ketches, La Poste, Merit Cup and New Zealand Endeavour, were one of the last throws of the dice for IOR.
New Zealand Endeavour - one of three new Farr-designed Whitbread Maxi ketches for the 1993-94 race 
But back to theorising about where IOR could have led in design terms. Would keeping a highly modified version of the rule kept ocean racing on its feet? Would it have prevented the almost total demise of classic events like the Ton Cups, the Admiral’s Cup, the Kenwood, the Southern Cross, the Onion Patch, the SORC? Who knows? Maybe it was all about economics or personal time management, but what I do know is that the defining legacy of IOR was its success at global continuity in offshore racing. To have made the decision to ditch this in favour of a hugely more flawed IMS was a grave mistake.

Would a boat designed to an updated version of IOR as suggested back in 1988 at the ITC meetings evolved into something equivalent to today’s high performance designs as typified by the IRC racers, TP52’s and Fast 40’s? Yes. Is the simple answer. Advances in lightweight construction, appendage design, carbon spars would have all contributed hugely, but the biggest single factor effecting overall design and concept would have been the removal of attempting to measure stability. Just as is the case today, boats would not have become more stable, but would simply have become significantly lighter and capable of carrying larger rigs effectively. These are the primary elements driving the performance in today’s designs.


To have arrived at this point in the genesis of the offshore yacht within the IOR style framework would have resulted in far more fleet continuity across the globe and possibly allowed the major offshore championships to survive the various financial challenges and rule uncertainties that killed them off.

Julian's article concludes with the above image of his 43 footer Backlash, with the caption "It's not easy to pick a single picture that represents the entire IOR era from 1970 to 1994, but this comes from a high point of the rule in 1985. Fleets were huge and there was enormous variety of design from a multitude of designers".