Bayesian Interim Report

Personally I suspect it was a Bermudian rig because it looks cooler...

One thing I'm genuinely interested to find out is what windspeed would have tipped it over with everything the same as the loss condition but keel down. Right now I'll bet that speed is still surprisingly low, and not actually that much higher.
 
DreadShips said:
Personally I suspect it was a Bermudian rig because it looks cooler...

One thing I'm genuinely interested to find out is what windspeed would have tipped it over with everything the same as the loss condition but keel down. Right now I'll bet that speed is still surprisingly low, and not actually that much higher.
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The keel is deep and heavy. Obvioysly the windage of that mast, and rigging, is enourmous. But I reckon the keel would nearly double the righting moment, which increases the wind speed by maybe 25%? It’s quite possible the wind speed was over 25% more than was needed to take the boat beyond it’s AVS. Though hopefully the AVS is noticeably increased too.
 
DreadShips said:
Personally I suspect it was a Bermudian rig because it looks cooler...

One thing I'm genuinely interested to find out is what windspeed would have tipped it over with everything the same as the loss condition but keel down. Right now I'll bet that speed is still surprisingly low, and not actually that much higher.
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Ok it's accepted that it tipped over...sailing yachts do this, but I don't think it tipping over should have so quickly sink,even beyond AVS it surely should have remained afloat for a reasonable time.
 
Chiara’s slave said:
The keel is deep and heavy. Obvioysly the windage of that mast, and rigging, is enourmous. But I reckon the keel would nearly double the righting moment, which increases the wind speed by maybe 25%? It’s quite possible the wind speed was over 25% more than was needed to take the boat beyond it’s AVS. Though hopefully the AVS is noticeably increased too.
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With the keel down it would have slowed everything a bit I think, it's not only the weight of the keel it's also the energy required to shift that flat area through the water..
 
billskip said:
With the keel down it would have slowed everything a bit I think, it's not only the weight of the keel it's also the energy required to shift that flat area through the water..
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With that much energy on the beam....I wonder if the fin would be strong enough to resist.....fully down with the majority of its immense weight at the heal.....a structure that is movable. What if it simply bent sideways against the water pressure
 
Bouba said:
With that much energy on the beam....I wonder if the fin would be strong enough to resist.....fully down with the majority of its immense weight at the heal.....a structure that is movable. What if it simply bent sideways against the water pressure
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I think with full rag up and a good breeze it could heel over and the keel would have to take that.
 
Bouba said:
With that much energy on the beam....I wonder if the fin would be strong enough to resist.....fully down with the majority of its immense weight at the heal.....a structure that is movable. What if it simply bent sideways against the water pressure
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Naively, it was taking sufficient force that the leeway was a couple of knots (the rest being taken by the dragging anchor). Doesn't feel huge?

The counter to that is what effect does that water pressure have on the righting arm? Hence my suspicion the increase in windspeed to roll it with keel down but everything else the same might not be as high as expected.
 
billskip said:
Ok it's accepted that it tipped over...sailing yachts do this, but I don't think it tipping over should have so quickly sink,even beyond AVS it surely should have remained afloat for a reasonable time.
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The interim report doesn't go anywhere near this. File that under "suspicious".
 
Thinking about the whole keel up thing - I wonder if the motion of the boat might have been uncomfortable at anchor (and motoring) with the keel down - like a yacht without it's mast having too fast a motion? That that's the reason they had it up, even though they had plenty of depth? Also, having it down would cause more wear on the mechanism, so might only be done when needed (sailing)(I know from a Tartan 37 I spent time on that the centreboard would clonk to and fro horribly if not sailing)? Or could keel-down have caused hunting at anchor - hence avoiding putting it down? Lastly, might something have got lost in translation from the Italian - rather than "motoring condition", saying "when not sailing"(which would include at anchor)? Just ideas, but so far I have heard no actual explaination why it was up.

Whatever the case may be, I have to commend a crew who can go from asleep to a flurry of pertinent activity in 6 minutes at the very worst part of the circadian cycle. They didn't win, but not from lack of effort.
 
dunedin said:
Can you provide any sources for these suggestions?
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No, so Hitchen's Law applies.

However, I'm sure we all watched the commentary at the time and followed the detailed Sailing Anarchy thread and, from memory, I have no recollection of anyone suggesting this was a true sailing yacht, and plenty of evidence that it absolutely wasn't. It takes on water at just over 40° heel. It has generators and air con that stop working at quite low levels of heel. It has a strict operating procedures that prevent it sailing in more than (IIRC) 15 knots.

So yeah, everything I'm saying can be discounted because I'm not going to back it up with facts. I'm still pretty sure I'm right!
 
KevinV said:
Thinking about the whole keel up thing - I wonder if the motion of the boat might have been uncomfortable at anchor (and motoring) with the keel down - like a yacht without it's mast having too fast a motion?
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It was widely reported that the keel was always left up at anchor due to the noise of it clanking around.
 
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Mark-1 said:
No, so Hitchen's Law applies.

However, I'm sure we all watched the commentary at the time and followed the detailed Sailing Anarchy thread and, from memory, I have no recollection of anyone suggesting this was a true sailing yacht, and plenty of evidence that it absolutely wasn't. It takes on water at just over 40° heel. It has generators and air con that stop working at quite low levels of heel. It has a strict operating procedures that prevent it sailing in more than (IIRC) 15 knots.

So yeah, everything I'm saying can be discounted because I'm not going to back it up with facts. I'm still pretty sure I'm right!
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We didn't all follow it.
 
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