Join Date: Feb 2000
Location: Annapolis, Md
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Re: Charter with disastrous Outcome
This is a very complex case. Cheeki Rafiki was a stock Beneteau 40.7. (These are boats that I know well have raced one for quite a few years) These boats were conceived as full fledged racer-cruisers. Sistership 40.7's have won just about every major race in the world beating grand prix level boats in a very broad range oc conditions. And although they were clearly production boats, they were not the usual production boat in terms of production methods or quality controls. The appendix in the detailed Inquiry Report describes the engineering process that Farr Yacht Design employed, which not only specified the structure but also the quality control and testing that was required. It also detailed the testing that Beneteau performed as well.
The report concluded that the design met or actually exceeded the structural standards of the day, and that the level of testing was extraordinary. When you read the testing and documentation process on these boats it become pretty obvious that few if any custom, or semi-custom boats, let alone production boats receive this level of care, testing and documentation of results. In other words the report appeared to conclude that there was nothing inherently wrong with the design or construction for its intended purpose.
But, it needs to be understood that like any relatively lightly built race boat, the safely margins are smaller on a purpose built race boat, and so greater care must be extended to inspect for damage whenever a impact occurs and repair any discovered damage. No boat is indestructible, but a grand prix level competitive race boat tends to be more vulnerable. This boat had a tough life for any boat.
To preface my next comments, in my opinion, like most production boats, boats like these were engineered for a specific purpose. That purpose included coastal cruising, fleet racing including offshore courses, and occasional passages offshore. A really heavily used boat with that design brief might sail 1,000 miles, maybe 2,000 at the most. A heavily campaigned race boat might sail a dozen major races in a season and dozen or more minor ones as well. And most race boats (but obviously not all) are retired from heavy campaigning after 10 years or so.
And it needs to be understood in the context that racing can put huge loads on a boat. They are sailed in all conditions with crew weight on the rail resulting in several times the stability more than what comes from their keels. They tend to be raced with the absolute upper limits of the amount of sail area that they can withstand and remain marginally controllable. In heavy going, they are steered as much with the mainsail as the helm. This places enormous loads on sails, rigs, and rig attachment points. And to a lesser extent, those loads end up as very high side loads on their keels, and keel structures as well. .
In the case of Cheeki Raffiki, this was a boat which had roughly 20,000 miles in Ocean crossings alone. It had been through major storms while racing and while being delivered. It had a number of groundings, and range of repairs and inspections. It had over 15 years of the hardest kinds of racing. The ocean miles alone represent 10 to 20 years of what would be considered as normal use. This boat had a hard life.
The report indicated that the probable failure mode was a delamination of the bottom of the boat in the keel area and possible/probably separation of the internal framing system. The keel bolts, backing plates etc, were not thought to have been the failure mode. This is very similar to the failure mode from the Cape Fear 38 that sank in the Gulf of Mexico.
In talking with one of the investigators for the Cape Fear 38 sinking, they concluded that the failure was damage to the primary structure that then transferred keel loads to the hull. The hull was never designed to support those kinds of loads. The hull then delaminated from a mix of fatique and impact fractures until it could no longer support the weight of the keel. In the Cape Fear a piece of the bottom was ripped out when the hull failed. In the case of Cheeki Rafiki it appears that the backing plates pulled through the inner hull and pulled off the outer skin.
I personally do not have adequate information to assign blame at this point, but I do think its telling that neither Beneteau or Farr are being dragged into this. It will be interesting to see how this plays out.
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Curmudgeon at Large- and rhinestone in the rough, sailing my Farr 11.6 on the Chesapeake Bay