Beneteau First lost her keel, four good men lost at sea.

As Structural Engineer I confirm that IMHO you are right but mistake can happen. Just look at the amount of steel in modern bridges compared to the heavy steelwork and massively bolted/riveted connections in old structures. However failures do occur as Westgate bridge and others demonstrate. Cars have got lighter yet stronger and protect passenger better now.

One question that may arise is what magnitude of force from an impact or grounding should a keel resist.

There is a saying that goes - Any fool can design a bridge to stay up, but it takes a clever engineer to design one that just stays up-

Perhaps there has been a bit too much of the " just stays up" philosophy in the design stage
 
As Structural Engineer I confirm that IMHO you are right but mistake can happen. Just look at the amount of steel in modern bridges compared to the heavy steelwork and massively bolted/riveted connections in old structures. However failures do occur as Westgate bridge and others demonstrate. Cars have got lighter yet stronger and protect passenger better now.

One question that may arise is what magnitude of force from an impact or grounding should a keel resist.

Arn't modern fast military aircraft attached to their wings with a few spots of Araldite?

They seem to stay on, most of the time.
 
There is a saying that goes - Any fool can design a bridge to stay up, but it takes a clever engineer to design one that just stays up-

Perhaps there has been a bit too much of the " just stays up" philosophy in the design stage

For my Institute of Civil Engineers interview I had an write an essay on "Is it best to design for a limited life of for posterity"

Its the perennial problem - lightness for performance, economy of structural members for cost (so it can be affordable) or overdesigned for longevity.

At that time I had designed a flyover with a brief of 15yrs design life. I am obviously a failure as its still in use some 35yrs later!!
 
The major tragedy is that the life raft was in a position where it could not be launched. In 2013 Yacht Nina went missing in the Pacific, last year another boat was lost in a storm with all crew on the atlantic (I can't remember the name) and now Cheeki Riffiki. In each case no life raft has been found either with or without crew. I am sure that at least two crew of CR ended up in the water and triggered their PLBs. We need a better design/education about the way life rafts are stored and deployed. I would be in favour of a complete ban on valise type life rafts. I wonder how may yachtsmen have died in the water when their boats have sunk taking the life rafts with them?
 
There is quite a good thread on Sailing Anarchy. http://forums.sailinganarchy.com/index.php?showtopic=157365

A couple of pics from the thread. The first is the keel grid from inside This is the bilge as well. The second pic is a close up of the underside. It looks like the keel grid detached from the hull and took a large piece of laminate with it. Many are of the opinion the keel suffered previous damage.

keelgrid_zps6d942d6c.jpg


keel_zps0864c138.jpg
 
The major tragedy is that the life raft was in a position where it could not be launched. In 2013 Yacht Nina went missing in the Pacific, last year another boat was lost in a storm with all crew on the atlantic (I can't remember the name) and now Cheeki Riffiki. In each case no life raft has been found either with or without crew. I am sure that at least two crew of CR ended up in the water and triggered their PLBs. We need a better design/education about the way life rafts are stored and deployed. I would be in favour of a complete ban on valise type life rafts. I wonder how may yachtsmen have died in the water when their boats have sunk taking the life rafts with them?
That is a bit harsh - there is very good reason why the liferafts are stored where they are on the Beneteau, and that is a result of hard won experience in other tragedies. Too many liferafts stored for example on the pushpit have been washed away in heavy weather long before they were needed - and there have been examples of lives being lost as a result. All liferaft positions are going to be a compromise, but IMHO the solution is one of the best.

Had the crew been in the water and conscious they could either have attached themselves to the upturned boat or made an attempt to launch the liferaft from the cockpit (I am a bit unsure about how much buoyancy a liferaft valise has)
 
That is a bit harsh - there is very good reason why the liferafts are stored where they are on the Beneteau, and that is a result of hard won experience in other tragedies. Too many liferafts stored for example on the pushpit have been washed away in heavy weather long before they were needed - and there have been examples of lives being lost as a result. All liferaft positions are going to be a compromise, but IMHO the solution is one of the best.

Had the crew been in the water and conscious they could either have attached themselves to the upturned boat or made an attempt to launch the liferaft from the cockpit (I am a bit unsure about how much buoyancy a liferaft valise has)

In this case, the thing that would probably have made the most difference to their chances of survival would have cost very little - carry a spare four man valise liferaft. They would then have been able to deploy it as soon as they detected a problem and cut it loose if they succeeded in fixing the leak. As it was, with just one liferaft, they would have been unwilling to risk wasting it and would have kept it stowed thinking that the problem was controllable.
 
There is quite a good thread on Sailing Anarchy. http://forums.sailinganarchy.com/index.php?showtopic=157365

A couple of pics from the thread. The first is the keel grid from inside This is the bilge as well. The second pic is a close up of the underside. It looks like the keel grid detached from the hull and took a large piece of laminate with it. Many are of the opinion the keel suffered previous damage.

keelgrid_zps6d942d6c.jpg


keel_zps0864c138.jpg

Seems odd they couldn't identify were it was leaking from if that is the keel bilge from a 40.7. If the bolt was leaking you would see it
 
Isn't that as much to do with improvements in metallurgy as design? Certainly a modern car uses more sophisticated steels than 40 or 50 years ago.

I doubt if there has been much change in the properties of the steel used for cars in that time. It is used a lot more intelligently than it was fifty years ago, though.
 
In this case, the thing that would probably have made the most difference to their chances of survival would have cost very little - carry a spare four man valise liferaft. They would then have been able to deploy it as soon as they detected a problem and cut it loose if they succeeded in fixing the leak.

Would it have been practicable to tow an inflated four person liferaft all the way to the Azores, in all weathers?
 
As someone with experience in fibreglass work my first thoughts on seeing those pictures were more focused on the colour of the laminate. I had seen that colour on a C&C that had been witness water intrusion from a past botched repair. And didnt this crew report taking on water but being unable to locate the source? Seems to me that this wasn't as sudden as first appearance....just to the unsuspecting crew. Sadly we have witnessed the loss of four fellow sailors.
 
I doubt if there has been much change in the properties of the steel used for cars in that time. It is used a lot more intelligently than it was fifty years ago, though.

Don't you believe it. A modern car is chockablock full of high performance steels.
A while ago I wanted to drill some holes on the back of seat squabs in my car. I was astonished to discover that even that was difficult......I struggled to drill the steel at all. (Yes the drill was fine!). One of the ways they reduce weight is to use thinner steel; that needs higher grades to be specified.
 
Would it have been practicable to tow an inflated four person liferaft all the way to the Azores, in all weathers?

No, but my point is that if they had had a spare liferaft aboard, they could have deployed it early while they were trying to fix the leak and cut it free if they had succeeded. As it was, they had a single liferaft aboard and would have been reluctant to do anything that could have meant that it was wasted. The spare could have been a fairly basic unit costing £500 to £600 - they would still have been better off in it than in the water as they ended up. The USCG knew where they were and arrived in less than 12 hours.
 
Seems odd they couldn't identify were it was leaking from if that is the keel bilge from a 40.7. If the bolt was leaking you would see it

The leak was probably quite slow until close to the final disastrous failure. By the time they noticed that it was leaking, they probably had an inch or two of water across the bilges and with it sloshing around it could have been difficult to see where it was coming from.
 
>if they had had a spare liferaft aboard

I've never known a long distance boat carry two life rafts it just adds more weight. If they had had a heavier boat they could have carried their life raft on the stern rail which we did not in a locker.If they had they would probably be alive now. It also seems they hadn't replaced the batteries, before leaving the UK, in the two PLB's and the EPIRB that was not fired but for the EPIRB there could be another reason.
 
The leak was probably quite slow until close to the final disastrous failure. By the time they noticed that it was leaking, they probably had an inch or two of water across the bilges and with it sloshing around it could have been difficult to see where it was coming from.

Err, any leak in a modern GRP /Plastic hull is surely a warning sign of very bad things to come, just like a leak in your Bath Tub, at home, ignore at your peril :( bath tubs, and craft, are not designed to leak, full stop .
With Timber craft, its sometimes a way of life, as the work, so to speak.
 
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