VIDEO - Sunk Bertram Discussion

After sleeping on it, this seems the most plausible scenario. It seems such an unreasonable event from one single wave because it is an unreasonable event. But if this boat had slowly been breaking up beneath the skin and behind the walls, then it makes complete sense that the right wave impact would trigger so many points of failure at one time.

I have encounterd the one in a million wave in 2/4& 3/6ft that would, if you were in the wrong position, swallow a poorly constructed vessel just like this one was. The deep steep trough that is encounterd when waves merge or conflict is more than a sea story!!I also think the rudder/ transom damage was caused by a midnight parts run attempt.

Actually had an owner do that on a Carver with Cummins. Big bang, but surprisingly no damage even to the trannys much less the boat.

Just a note with no bad intentions, but your posts will always be viewed with a jaded eye as long as you "speak" as if you are texting like a teenager and you do not spell check.

More like pure fantasy.

I am thinking this way too. If you look at pictures or videos of a 63 from the helm, you cannot see the bow at all while driving. I am thinking it is possible the bow had been coming apart for some time as he was running and the captain was unaware until it gave in completely. A boat that size running at cruising speed could shed skin where you cant see it or feel it from the bridge. There was only one other person on the boat (who was also on the bridge). If it peeled like "Certifiable" he could have been down to the core material on the bow when it stuffed and there was no strength left.

http://www.yachtsurvey.com/bad_news_for_Bertram.htm

At that point it would "cave in" just like he described. It would have been sort of like your hood popping open while going down the highway. This would explain the foredeck being pulled off.
Now the transom? I am still stumped by that one....

Pure speculation: If the boat came down on the starboard aft (which would explain the rudder folding) is it possible that the boat racked enough to break brittle corners when the hull loaded in a way that was never in the design considerations? Except for a hurricane grounding or a drop from a travelift, I can't imagine how a boat would experience such an impact on a single point.

Reality is that when the prevalent wave height is 3-4' the significant wave height will be 5-7'. Usually the waves come in sets of 3 and from about 10-15* off prime bearing, counter clockwise in the northern hemisphere, clockwise in the southern. If I'm coming off the back of the first of the 7's, especially one that has locked with a common wave making it steeper, at a speed (and 25kts would be that speed) where I'm slowly passing the waves, I'll start surfing and by the time my bow is going down into the trough, I'll be doing 27-30 kts and I'll have all the pressure of that wave pushing behind me shoving the bow into the trough and wave in front of me. There's a lot of energy absorbed and transfered at the bottom. This is an expected condition though and is far far from "extreme". EVERY boat that is meant to operate in unprotected waters should easily be able to run in these conditions all day long. In the picture in my avatar I'm on a clients old 58' Predator just leaving Glen Cove LI. Less than an hour after that picture was taken, I was bucking 16'ers coming around Sandy Hook and proceeded to run that entire day in 12' following seas all the way to Norfolk VA at 27kts. That boat was perfectly comfortable with it as should any boat meant to run offshore.

That's one of the issues with composite construction, often the failure mode is completely hidden until it goes catastrophic. Most likely having a view of the bow would not have provided any lead indicators.

The transom came from bouncing along the bottom for a mile in a storm that came by after the boat sank. That is only consequentially related damage. All the damage at the stern is typical of a oat bouncing along the water for a ways.

Listen, the fact of the matter is, a lot of us have been asking ourselves, could this happen to our boats, Bertram or other brands? I know for myself, I called the factory that manufactured my boat and found out exactly what process was used to make my boat. I did some homework and I feel more comfortable with what I have.

But, the real question is, how many boats, say in the past 30 years, have experienced this kind of failure, if it is proven that this boat actually sunk as a result of faulty workmanship, and the verdict is still out on this? My guess is that the number is extremely small, compared to the number of boats built. Is there any record on the number of hull failures?

That raises an interesting question. What % of fiberglass boats are still floating 30 years later and is that number increasing or decreasing with new coring, resins, etc.. I'd love to hear that # broken down by manufacturer.

Other than a Jet Boat or Outboard I am yet to see a propeller driven boat (CPP Excluded) that can do this with or without Electronic Controls.

USCG has this information but re-sale value is normally a better indicator IMO as the market does a good job of separating the wheat from chaff...

That video is too disturbing to watch in one sitting, I had to stop and walk away several times. Although there are several theories explaining how the boat got to where it is, not one can explain why the hull is so **** thin.

The very beginning of this video shows a profile shot from the helm to the tip of the bow. You can draw a straight line between these two points. To me this is an indication that this boat was upside down resting on the remainder of the bow and helm station. The bow has been basically ground down to the condition you see it in now. Some of what you are seeing damage wise was caused by the time spent on the ocean floor.

It looked to me like the tower is still up, (or at least the outriggers). That would make it unlikely that the boat was ever upside down. Even if it was that would not make it delaminate.
Also, the "full throttle reverse" theory is unlikely. The engine mounts look intact and most electronic controls have built in delay's to prevent that sort of thing.

All i can say after watching the video is i dont think that big broad flat area between the chine and sheer made up of 2 to 3 layers of biaxe cloth on each side of some 3/4 inch foam core stood a chance against tons of water being driven down into with a 100 thousand pounds of boat behind it.

Regardless whether the foam was defective or not there is simply not enough material there without any sort of interior framing or structural bulheads to withstand the kind of forces that area of the boat is recieving.

My take on this is if the history of the failed secondary bonding on the bulkhead tabbing on other Bertrams is indicative of how well this particular Bertram was bonded at the deck cap and the hull,than there lies the beginning of the failure.This bonding may well have been failing from the beginning of the 1st sea trial and may have very well have been totally seperated before the boat left that day as this unbonding would have been hard to detect unless somebody was looking for it.

So it was just a matter of time and the right wave to finally cave in that paper thin hull as once the deck and hull connection was no longer solid a major structurial component of that area was gone.
So the boat goes into a particularly large trough and takes a slight dive . The hull no longer strengthend by the deck folds in like a wet shoe box and the water pressure being redirected upwards by the folded back forward hull section is shot up under the deck and foldes it back and destroys the interior.

GAME OVER

Massive deceleration bends the tower and the weight of the captain and crew against the console dislodges it.

Only the sealed off engine room is keeping this thing from immediatly sinking.

That there is all fact

Now how the transom recieved such a clean break is a mystery to me. I am not real famaliar with where the stern cleats and hawsepipes is located .From the video i would say the cleats are gone with the stern section and the break looks to have occurred where the hawse pipes pass thru the coaming?

I might be able to buy that the transom damage occured from the boat grinding across the bottom if 1. There was some real bottom there to grind on not sand , and 2. The aft section of the bridge had similar damage.There is no way that boat bobbed across the bottom balancing on just the transom .
There is something fishy going on there.

As far as the rudder being bent i can say i have twice pretzeled a 1 3/4 rudder shaft grounding it and that damage from a 100 thousand pound boat sitting on it as the boat came to rest on the bottom is to be expected.

Props are Nibral and sharp they simply settled in the sand the rudders are broad and deeper and the shafts are not hardened and the housings are soft bronze.

Just for the record i used to work for one of the leading Custom Carolina builders for a stint ,and comparing that Bertrams constuction against it would be like comparing a ping pong ball with a golf ball.

I agree about the bulkhead tabbing. You could see one detached in the original set of pictures. It wasn't "torn". I looked more like it "de-bonded"

and this
" So the boat goes into a particularly large trough and takes a slight dive . The hull no longer strengthend by the deck folds in like a wet shoe box and the water pressure being redirected upwards by the folded back forward hull section is shot up under the deck and foldes it back and destroys the interior."

is almost exactly how I pictured it too......

This is exactly what it looks like on many performance boats when they stuff. The deck peels off and it ends up looking like they ran into a wall. They are usually going 70-100mph but then they only way 10,000-15,000 lbs.

I could imagine a 100,000 lb yacht like this hammering into a rouge wave and just exploding like this. No, it should not happen, but I can see it.