Well, let us be grown ups about this. Clearly, with the prospect of a 50Kva generator rattling away allied with domestic pumps, HVAC plus other ancillaries……not to mention a remote UMS panel outside the engineroom………the door was closed.
Put the bulletproof “powerabout” in front of a camera and no doubt his/her experience and delivered would be seamless.
It is my belief that this contributor makes some valid points particularly regarding permanent ballast and the swing keel.
I am distressed that you are disappointed with his dissertation…….not.
I only referred to one point.
It was you jumping to conclusions that the wrote off the whole vid
PS what dissertation?
Your reference to one point was churlish. Clearly, the contributor was mistaken. We all realise that.
He also mentioned the crew made a mistake like many others but what mistake was that?
Besides being on a boat the NA’s designed and class passed that sank in a bit of wind?
Yeah, the last time I was on any kind of floating anything that was anchored and I thought I was in danger from capsize or sinking in a storm was when I was caught out in a nasty storm in a Penguin. (12 foot sailing dinghy)
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I am amazed that so many people assume the yacht was good and the crew was bad.
Like na’s and class havent designed death traps before.
In actual fact, he was very guarded and measured in his commentary regarding the crew.
“In a bit of wind”……somehow, this bit of wind happened to heel this 56m bare pole vessel to a position whereby down flooding occurred allied with an exceedance of calculated AVS. An extreme event.
It is apparent that the traditional means of determining Metacentric Height via an inclining experiment is no longer valid and the “NA”’s need to review their approach regarding stability calculations. Perhaps a downburst experiment…….
Don’t be too hasty in blaming Naval Architects. They design to rules established by other entities.
Away from the “Aussie Debating Club”:
We were once hit by a Derecho storm about 0300. It sounded like Satan’s Own Freight Train coming at us, I barely had time to get all the hatches closed. This was to keep rain out of the cabin, not to prevent sinking. I was very worried about dragging anchor into someone or something else or having someone upwind drag into us. The wind and rain were so intense I could see nothing at all. We were in no danger whatsoever of the boat sinking or even laying over much past 30 degrees.
Sudden storms with winds that can easily be in the 60-80 knot range or worse - and this one was much worse* and caused widespread damage - are a thing in this part of the world at least that can happen with little warning. They do not leave a trail of capsized boats except for maybe dinghy types. Boats that need special handling at anchor in a storm in 4 foot waves are just not a common thing.
- at first it was assumed to be a giant tornado outbreak it did so much damage.I also have a photo somewhere of being chased by a waterspout, these are assumed to be dangerous in being able to suck people off the boat, but not actually able to capsize a boat.
Sure it was designed to a standard but the weather went past it most likely?
Not hard to do a calc on the force required to hold it down and the force x wind to do that, then how long it would take to sink it with the known downflooding openings.
Pretty sure we are going to learn all that soon and how many other yachts might have sunk had they had been in the same conditions.
This one has a huge rig so maybe the worst case ever designed and just got unlucky?
STABILITY BOOK OF YACHT
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None of the hundreds of large yacht engine room doors I have passed through many times including those large Perinis and still regularly pass through have a second door in series with the w/t door. Some have a “cosmetic” door covering the sliding w/t door between crew and guest spaces.
My take on that video was it is just another pile on bit of speculation click bait for the magazine.
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Methinks the GA explains the WT vs. joiner door theory neatly …. Just sayin.
Separately … if she rolled to SB, the engine room WTD in any case would then have been located on the „high“ side and not contributed to progressive flooding until the yacht settled in the water well beyond the centerline…. Ahem. Good news for the chief if reports are to be believed……
So … did most or all of engine room flooding come via the SB ventilation openings (if provided) until it was too late?
Also, for a separate line of thought, sliding glass doors are typically balanced against one another on the drive belt so if the belt is intact, they don’t move until actuated. Never seen that tested at 90 deg however……
And the yacht I’m on has exactly a sliding WTD at eng rm Fwd Bulkhead tktop level with a joiner door right in front. As do many by same builder. It’s pretty common.
Might that joiner door be several feet away and at the base of stairway up to guest area and at same level as galley and crew mess?
The space under discussion is a technical/storage area and unless used to access the port side shell door is not guest accessible. Even when used for tender boarding the deck hatch has to also be open to reach the stairway down to that level. Having spent a lot of time on that class of Perini I call BS on the shell door or deck hatch leading to it being relevant.
Steamer,
I think we are posting at cross purposes.
There was rumour the BAYESIAN engine room aft bulkhead WTD was in the open position at time of the incident due to crew error.
I have no idea - but regardless, it may prove irrelevant because the eng rm aft bulkhead WTD door appears from the Perini GA Plan to be at port side. You might know better from a near sistership …
So assuming the above “port side” WTD location is correct, even if the lazarette area flooded due to any reason … with the yacht laid on her “starboard” side, the engine room WT door would have then been on the high side above water and not a cause of progressive flooding of the engine room or conversely - from a flooding engine room into a perhaps otherwise sealed lazarette.
At least until the yacht settled deep in the water on her starboard side and was flooding to a sinking situation regardless because of the various immersed ventilation openings and hatches / doors (time of incident open / closed positions presently unknown) serving each compartment. There was no one onboard to make closures at point in time. However as one poster mentioned, the Belimo dampers might have spring closed (hard to say if they would close against water inrush … it’s only a spring not a powered flap….)
There is no way a closed eng rm WTD would have created an air bubble preventing eng room flooding if it was closed - because the engine room has vent opening on PS so the air inside was not captive.
So in effect, it may prove that it didn’t matter what position:
- The engine room aft bulkhead WTD was in at time of incident
- The bathing platform PS shell door was in at time of incident
- The stern shell door was at time of incident
Because progressive flooding not affected by the position of the engine room WTD was already taking place in multiple compartments.
Something to think about if the finger of blame lands on a crew member that may have left that particular internal WT door open at the time of incident for some reason. And MOST IMPORTANTLY - it is NOT yet confirmed that was the case
Happy to hear more thoughts on the flooding topic.
The initial ABS Load Line Assignment Form LL-11-D showing all the openings might prove helpful if it is somehow “found” on the internet …
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Another thing that puzzles me here: the speed of the sinking. Let’s say all doors/hatches/windows were closed. Only ventilators to manned- and machinery-spaces were open. I just don’t see a vessel sink in 30 minutes(?) from down-flooding through a couple of ventilators . Seems to me it should have taken longer. What is the square-area of the submerged ventilators?
What could have happened is :
- Vessel is knocked down. Water floods through the ventilators on the submerged side.
- The people panic. They open doors and hatches to escape. Including a WTD near the new waterline of the vessel.
- Because the vessel is on its side, resealing interior doors along the avenues of escape is going to be difficult, even if people remember to do it. From my experience, once something floods into a space down below, people just to run. They don’t seal up anything behind them. Let alone doors now hanging at 90 degrees from normal.
- Flooding through the ventilators lowers the draft until the exterior WTD opened to escape now ships water. The rate of flooding rapidly increases. The water floods down the avenues of escape.
But until the exterior WTD is opened, I just don’t see a vessel that size sinking that fast just from ventilators.
Just more speculation…
There are engine room and lazz ventilators on both sides. The port has one just forward of the port shell door and one aft. I don’t recall the exact ducting because I never cared much about it other than noticing it was rather complex compared to a not-a-sailbote arrangement but they are configured so that submerging to the rail on a tack doesn’t sink the boat. The exhausts are piped so that it doesn’t matter if they are deeply submerged, the gases just exit on the high side. An early report said it went down bow first but, again, pure speculation until the crew interviews are made public. Since everyone else is speculating, why not continue. If the tender bays were open and took on water that would have added a few tons forward. If the starboard deck was awash it is quite possible a large slug of water took out the saloon doors and continued forward, taking everything loose with it into the guest areas and down to the galley and crew spaces. The bow would have gone deeper. I have seen a “slug” of boarding water bend the steel ladders on the deck of a containership and stove in the side of the house on a 125K ton tanker so breaking a tempered glass door of substantial area is not out of the question. The doors would not have to be open. This blaming the crew is bullshit.
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Freighterman 1,
Yes, I have been wondering the same myself……particularly when you view the main deck GA. Perhaps, by way of speculation, the starboard fixed glass saloon panels stove in owing to the speed and severity of the knock down. The open stairway to the lower decks is just above and offset to starboard. The fact that the divers discovered 5 of the deceased in one port side cabin possibly indicates that there was an early ingress into the guest areas forward of the engineroom watertight bulkhead.
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