Hull Cracked / Deck Damaged - Beneteau 311

[Jackdaw]

If we're going to compare your anecdotal observations:

• Of the failures you quote, how many of them were supporting hull structure failures as opposed to chainplate or rig failures? In this instance the chainplates and rig are still intact, it's the supporting structure that failed.
• Of the failures you quote that were actually supporting structure failures, what were the ages of the boats? If we're comparing apples to apples, age is a factor.
• Of the failures you quote, how many of each model were produced? This figure gives us a failure rate for the design, design being in question right now. For example, there were roughly 7,000 Catalina 30's produced compared to roughly 120 Beneteau 311's. An equivalent failure rate would be 58 Catalina 30's to this one B311 and again, that's supporting structure failures.

Please refer to the pictures I provided of my previous boat. Although difficult to see in the perspective, both the jib and staysail overlapped the mast and the chainplates were bolted to the hull sides. That's a 1970's design.
Yet he designed the most successful 30 footer in history, naval architect or not. I'd suggest using a different example.
What do you mean up to snuff? What about the Catalina history was not snuff-worthy? I'm not suggesting Gerry Douglas' work is not outstanding, it certainly is but what was in defect before he arrived?

Well right, they are my observations. But I actually saw them. Two of the damn things almost hit me. And yes the failures are related to failure of the chainplate support area, but that's kind of my point. ALL these designs are good until they fail. That failure is caused by damage, wear&tear, or material breakdown. When in good condition, rigs don't just fall down. That's true on ANY boat. Thats why the OP needs to sort out his boat.

The pix you show are cutters. That's totally different. And for whats its worth, I don't think that they are Catalinas.

I sense you're starting to take this personally and that's not my intent. So I'm going to drop this.

 

[Old Skool Neil]

Nothing personal here. I'm merely questioning statements that I find incorrect or skewed in my personal experience. Your apparent preference for current engineering and construction is noted. It's not my choice but I haven't derided yours.

 

[anchorclanker]

I believe there is enough information to conclude this boat is original/unmodified. That leaves two possibilities for failure, previous unknown and unseen damage, or a design flaw.

Going solely on the OP word, this boat passed a survey showing no outward appearance of previous damage or repair. Also, the damage happened to BOTH sides, which almost totally rules out previous damage.

Over tensioned shrouds? I could see one side letting go, but not both. All structures have a weakest link, and like a chain, its doubtful both sides of the boat could be equally strong or equally weak. Excessive tension would tend to pull whichever side was weakest up, reducing tension below the threshold, it should have spared the other side. OTOH, if the shrouds were too loose all bets are off.

But even if that were the case, I am not sure we would want to see the deck tearing open? If I had one of these I would be quite concerned. And I would likely look into adding a knee (or knees) or some other type additional structure to increase its strength in that area.

 

[wetass]

I believe there is enough information to conclude this boat is original/unmodified. That leaves two possibilities for failure, previous unknown and unseen damage, or a design flaw.

Going solely on the OP word, this boat passed a survey showing no outward appearance of previous damage or repair. Also, the damage happened to BOTH sides, which almost totally rules out previous damage.

Over tensioned shrouds? I could see one side letting go, but not both. All structures have a weakest link, and like a chain, its doubtful both sides of the boat could be equally strong or equally weak. Excessive tension would tend to pull whichever side was weakest up, reducing tension below the threshold, it should have spared the other side. OTOH, if the shrouds were too loose all bets are off.

But even if that were the case, I am not sure we would want to see the deck tearing open? If I had one of these I would be quite concerned. And I would likely look into adding a knee (or knees) or some other type additional structure to increase its strength in that area.

Personally, I am still putting my money on shrouds that were tensioned over what the designers figured for an outside limit - The reason is that the hull didn't fail the same way on both sides according to the OP. He stated "A similar bubble was starting to swell on the starboard side at the chainplate U Bolt. " (Emphasis added). This isn't the same failure as it sounds like it was starting to pull the u-bolt up through the deck AND this could have occurred simultaneously, not afterwards, and just went unnoticed until the crack on the opposite side was found. IN other words, the deck integrity on the starboard side won out over the sheer on the port side. It also tells me that the shrouds and u-bolt was actually stronger then the attachment point (hull). If thats right, then I think if any argument is to be made against this design, its that on most hulls, the rig is the first to fail. On this design, its the hull/deck (But again, with so many out there and so few failures, its apparently adequate for how they are used).

 

[wetass]

My guess is the previous owner wanted to have the rig "tuned up" to show off its sailing abilities and to maybe make the boat feel/sound solid. He either did it himself or hired a horrible rigger and then way way way overtightened the rig. I have seen it before where if you brush by the stays, it feels like you hit the corner of a brick wall.

 

[Jackdaw]

Occam's Razor, guys.

The notion that DESIGN of an entire generation boats is bad based on one failure is a bit far fetched, when the simplest and probably mostly likely explanation is CONSTRUCTION ERROR on this one boat.

 

[sailandrelax]

I think perhaps we are starting to beat a dead horse here without any further response from the OP as to what really caused this.

Would I buy another Beneteau 31 or a Catalina 34? Of course -- 2 known problems like this between hundreds of boats of both brands simply doesn't point to a design flaw or even a question of one.

By the way, there is extra support (knees) in these boats at that point on the hull as our Canadian friend pointed out. In the B31 it is that tube he photoed, and in the 323 and 311 it is located behind the cabinetry (the cabinet attaches to it.)

Speculation without any justifiable evidence begins to lead to people taking things personally and tarnishing the reputation of designers with many years of excellence, all without warrant. We can continue to guess, but I'm not sure of the benefit.

Catalina & Beneteau are strong, worthy brands, but nothing is impervious to X,Y, Z unknown/unexpected stress.

 

[Old Skool Neil]

I really hope Raul reaches a satisfactory outcome and hope he posts back with a debriefing. Without it all we have is speculation and there's been puhlenty of that.