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Old 13-08-2014, 14:45   #76
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Re: Alpha 42 Designer's Rebuttal

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Brad, that made for some interesting reading, thanks for posting it. I'll stand corrected that some cat's have successfully deployed them in actual storm conditions. But reading the stories also shows that nearly as many failed as had success.

PBR, absolutely, the conditions we had where only gale force. Probably doing nothing would have ultimately been ok but that's not in my dna. I still think, and most likely will never be convinced otherwise, that due to the bridgedeck of a catamaran, they should not use sea anchors in storm force conditions due to breaking waves. I don't think most can handle the force of water exerted on them where mono's can. And, as happened to the Catana, if the bridle breaks, they stand a chance of flipping over backwards.
As a builder I can tell you categorically your theory about catamaran bridge decks in breaking waves is dead wrong, in my opinion catamarans ride even better on sea anchors than mono hulls due to their light displacement and stability. I think Brad and I have provided enough data based on experience to support having a sea anchor on board. My only reason for carrying on the dialog this far is to protect the readers of this thread from what I consider to be flawed theory and conjecture. (No offense)
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Old 13-08-2014, 15:11   #77
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Re: Alpha 42 Designer's Rebuttal

Believe me there is no offense taken as the only reason I brought up your post is to protect the readers from deploying a sea anchor in the - IMO - false assumption it will protect them during storm situations. You haven't provided anything except opinions. Brad provided some good info from 30 years ago.
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Old 13-08-2014, 15:37   #78
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Re: Alpha 42 Designer's Rebuttal

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Believe me there is no offense taken as the only reason I brought up your post is to protect the readers from deploying a sea anchor in the - IMO - false assumption it will protect them during storm situations. You haven't provided anything except opinions. Brad provided some good info from 30 years ago.

I dont get it, what you can do in 50 knts with a disabled cata and a dangerous rocky lee shore in your way????
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Old 13-08-2014, 15:53   #79
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Re: Alpha 42 Designer's Rebuttal

The same thing they did - call for help??? That wasn't the situation here though. I guess if they had been 1 mile off shore with the same situation then the outcome would have basically been the same - the boat's lost.

But the discussion is so far off topic I'll leave it.
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Old 13-08-2014, 16:17   #80
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Re: Alpha 42 Designer's Rebuttal

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The same thing they did - call for help??? That wasn't the situation here though. I guess if they had been 1 mile off shore with the same situation then the outcome would have basically been the same - the boat's lost.

But the discussion is so far off topic I'll leave it.
Thank you!
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Old 13-08-2014, 21:08   #81
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Re: Alpha 42 Designer's Rebuttal

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As a builder I can tell you categorically your theory about catamaran bridge decks in breaking waves is dead wrong, in my opinion catamarans ride even better on sea anchors than mono hulls due to their light displacement and stability. I think Brad and I have provided enough data based on experience to support having a sea anchor on board. My only reason for carrying on the dialog this far is to protect the readers of this thread from what I consider to be flawed theory and conjecture. (No offense)
pbr - as a builder, what are your thoughts on the wave-piercing-bow design? I understand the general concept behind them - but it just seems a bit suspect to me on a cruising cat...especially in big waves like in the A42 case. It seems that with the downward force of the design (i.e. - piercing the wave - not rising with it), you'd be much more likely to experience a lot more force of water at the bridge deck beam - which would then drive you back just as reported with the A42.
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Old 13-08-2014, 22:12   #82
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Re: Alpha 42 Designer's Rebuttal

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I was part owner of the company .
I took this as part owner of a company that produced sea anchors, not actually as a builder of the cats. PBR, which cat did you build?

Good question Smack.
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Old 14-08-2014, 03:30   #83
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Re: Alpha 42 Designer's Rebuttal

Manta possibly? Think they built around 130 or so. Just an uneducated guess, but the Mantas were very well equipped. Can't think of any other cats that could possibly come with a sea anchor
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Old 14-08-2014, 04:51   #84
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Re: Alpha 42 Designer's Rebuttal

Never been in survival conditions, but as I have ocean voyage in the close future in front of me, I have spent time thinking of preparations and plan what to do.

The biggest issue I see with a sea anchor is ---- What is the upper limit conditions (wind speed, sea state) a short handed crew can perform a successful deployment of a sea anchor. Whatever it is, much earlier than when you actually would need it.

Secondly, I think its a (low) percentage game if you actually going to be successful. Hurt yourself, damage things like getting the whole thing wrapped around the rudders, unless doing very very early and had some practice before in calm weather.

My plan as I'm thinking is .... keep it simple. Rather than a very early deployment of sea anchor, use speed to try to escape the worst of the predicted weather. When things starting to be real bad, if the boat starts surfing too fast, start dragging things after the boat. Start with the smallest anchor. If still too fast, drag another. If going too slow and risks of being popped, cut one off. If running out of sea room and cannot use the upcoming land for protection, call rescue.

So in short, keep it simple. The boat can take more abuse than man so save your energy by not doing too demanding tasks.
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Old 14-08-2014, 05:44   #85
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Re: Alpha 42 Designer's Rebuttal

We are getting off topic for this thread (and there have been other threads on storm tactics for catamarans). Sure, drogues (and especially series drogues) have their proponents and would probably be my first choice SO LONG AS I HAD SEA ROOM. But again, this was not the issue with the Alpha 42.
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Old 14-08-2014, 06:37   #86
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Re: Alpha 42 Designer's Rebuttal

P.S. In the case of the Catana 44, the bridle did not break. Rather, the crew had attached the bridle to one of the bows and the center of the forward cross-member - contrary to common sense and Paratech's instructions. When the boat was recovered, not surprisingly, the cross-member had failed at the center-line.

It should be clear that the forces generated by a sea anchor in 80 knot winds and 25-30 foot seas (as experienced by the Catana) are far too great for an aluminum cross-member. What is more, by deploying the sea-anchor off the boats centerline, the boat would tend to lie to an angle, rather than facing the seas head-on. Finally, one should also pay attention to the length of the tether. Bayete deployed only a 400 foot nylon tether, whereas Paratech recommends at least 10 - 15% of the boats LOA - in the case of a 44 foot Catana, 440 to 660 feet in length. A nylon tether stretches under load and, the longer the tether, the less force that will be generated on the attachment points for the bridle.

I would agree that an improperly deployed sea-anchor likely increases the risk to a catamaran in those conditions. I do not believe that we can conclude, however, that this would be true for a sea anchor that was properly deployed.

Brad
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Old 14-08-2014, 06:50   #87
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Re: Alpha 42 Designer's Rebuttal

Cruisingkrol, I just saw your post and congratulations on the purchase of your new Alpha 42. I, for one, still very much like the design and would think that you can take some comfort in the fact that the design has now had a rather extreme shake-down! Furthermore, in spite of the loss of hull#1, that Hank Schmitt still considers the boat to be very well built overall.

Alpha have indicated that they have addressed the leaking portlight problem in subsequent hull numbers and I gather the same is also true with respect to the jib sheet leads. Can you advise how they have addressed the issues with respect to the steering system? I assume that they are now thru - bolting the rudder heads to the rudder stock? Have they upgraded the welding of the internal stainless steel rudder plates to the rudder stock? Are there any other upgrades?

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Old 14-08-2014, 09:39   #88
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Re: Alpha 42 Designer's Rebuttal

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pbr - as a builder, what are your thoughts on the wave-piercing-bow design? I understand the general concept behind them - but it just seems a bit suspect to me on a cruising cat...especially in big waves like in the A42 case. It seems that with the downward force of the design (i.e. - piercing the wave - not rising with it), you'd be much more likely to experience a lot more force of water at the bridge deck beam - which would then drive you back just as reported with the A42.
The reverse wave piercing bow for a racing cat can offer reduced drag and pitching at higher speeds. I think in a cruising cat it can allow more spray and water on deck than desired. The reverse bow design when taken to the extreme can make anchoring a bit more problematic as well.

I have recently put a new design concept out with the Manta 46 that incorporates what I call a modified Z wave piercing bow that gives you the low wave making drag and extended waterline of a wave piercer but with the flair, reserve buoyancy, and profile of a conventional bow above the water line to reduce water and spray on deck .

As for the sea anchor, there are several choices for safe deployment from actually attaching to the existing anchor chain and deploying with the windlass as you would with a conventional anchor and its bridles, or deploying from the cockpit. When venturing offshore it is simple enough to pre-rig either way so it is ready to go when you need it. As I said before it is a nice option to have on board, and I would include it in any safety package for a vessel cruising offshore.
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Old 14-08-2014, 09:49   #89
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Re: Alpha 42 Designer's Rebuttal

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We are getting off topic for this thread (and there have been other threads on storm tactics for catamarans). Sure, drogues (and especially series drogues) have their proponents and would probably be my first choice SO LONG AS I HAD SEA ROOM. But again, this was not the issue with the Alpha 42.
Again the point and my original point with the Alpha cat situation is, with a sea anchor they would have had a much better chance of performing some kind of repair with the bows into the waves and rudders not flopping around. The captain in fact stated he almost lost a couple of fingers while working in the confined space with the uncontrolled motion of the boat and rudders.
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Old 14-08-2014, 10:16   #90
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Re: Alpha 42 Designer's Rebuttal

pbr, I understood the point you were attempting to make. However, even with a sea anchor deployed, the rudders would not remain stationary: not all waves will come from directly ahead and, in addition, the boat will yaw. While the motion with a sea anchor deployed may have made their efforts at making repairs more comfortable, with one of the rudders bent on the stock at an angle and ther other spinning on its stock, they would have still been unable to effect repairs sufficient to enable them to continue underway.

Brad
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