Boat sunk in Glacier Bay

[twistedtree]

The latest NOAA ENC (vector) chart does, raster charts are no longer updated. The thing I haven't found and would love to know is how to figure out when/how the soundings were done for an ENC, with good old raster charts they are listed in the corner somewhere, like the attached example.

I agree. That's VERY important data that seems to be lost with the ENC charts. Or at least I can't find it.


Has anyone found this info with ENC charts?

 

[HTurner]

Let's just be clear that there is nothing to suggest stabilizers had anything to do with the sinking.


And to put minds at ease, in a strange sort of way, a friend got out of place in a narrow entrance earlier this summer and struck and grounded on a rock, then backed of as the tide rose.


The impact scratched up the bottom and broke off the fiberglass shell of one fin, leaving behind the shaft and stainless core of the fin. No other damage other than to the rock. He continued on and is still cruising without interruption.

Sounds like he was lucky, nothing more.

 

[twistedtree]

The owner wrote: “The crew made a valiant effort to secure the boat with both a front and rear anchor, but Mother Nature was too strong and the rocks breached a hole in the bottom of the hull by tearing off starboard stabilizer.”

Ah, OK, there you have it. So it would be really interesting to understand how they were installed. I have seen installations with nothing more than a block of wood epoxied to the hull and the actuator through bolted. I would never go to sea with an installation like that. Naiad even calls for completely glassing over the block so it's effectively embedded in the hull layup. But that doesn't seem to always get done. I greatly prefer the ABT design where instead of an epoxied wood block, there is a huge integral steel flange that spreads the loads across the hull.

 

[Alaskan Sea-Duction]

I suspected the white object on the port side of the exposed hull was a stabilizer. Not a fan of them. Basically a rudder on the side of your hull with no skeg to protect it. The stress on that part of the hull, especially a wood hull....

Sent from my SM-G715U1 using Trawler Forum mobile app

A few years ago, a similar boat sank off the Oregon coast. It had fin stabs. They determined a crab pot got wrapped around the fin, rolled the boat.

 

[Max Simmons]

I too remember going on her at one of the boat shows after seeing her for years from the Ship Canal bridge on my commute into Seattle. What a shame.

 

[jimdavi]

I installed keypower because the fins are foam covered with a stainless frame. They are soft under significant load and will break, not the hull. At least that’s the plan! Also my hull was reinforced properly, eg coosa, G10 and much larger area than the actuator. Then epoxy and fiberglassed over.

Be aware of “availability bias”, ( human tendency to think that things that come readily to mind or recently are more representative than is the case) on fins cause sinking.

 

[twistedtree]

A few years ago, a similar boat sank off the Oregon coast. It had fin stabs. They determined a crab pot got wrapped around the fin, rolled the boat.

I'm trying to imagine how a crab trap could roll a boat, but struggling.....

 

[Alaskan Sea-Duction]

I'm trying to imagine how a crab trap could roll a boat, but struggling.....

Me too, but that was the finding. I will do a search and see if I can find it.

 

[Portage_Bay]

In some areas the sand moves in waves. Just like water waves but more slowly. A crab pot buried in the sand is a very effective anchor. The right combination of vectors from seas, current, wind and boat direction and speed might be capable of capsizing a boat.

Sent from my SM-T500 using Trawler Forum mobile app

 

[Fletcher500]

Me too, but that was the finding. I will do a search and see if I can find it.

https://news.yahoo.com/probe-boats-sinking-leads-crab-013237184.html

This was a fishing boat, not a recreational so not sure if it is what you are referencing: Crab pot lines and Stab interaction. Either way, a low frequency and freak event. We have quite a few lobster pots in our area starting in October and not having two more things sticking out of the water to snag them was one of the reasons I went the Gyro route. People have posted on here as well as other boating sites they have tangled their fins with these, as well as long line fishing gear. Probably easily removed in most cases if one is willing to get wet, and it’s safe to do so considering the sea conditions.

 

[sunchaser]

For those of us that were involved with on the job safety programs whether civilian or armed forces, there are several safety 101 reminders. The most straightforward? The sinking resulted from an unsafe act or practice. Even the owner says the same.

 

[bowball]

It does argue for a life raft.

They probably couldn’t deploy a tender if it was on the boat deck and not being towed.

Yet, how does one enter a boat deck mounted life raft, as so many are?

 

[Old Sea Dog]

If you go back to the original pic, it shows the tender crane raised. So my assumption is that 2 people launched the rib that is in the pic with 2 people in it. The rib would then pick up the 2 that were still on the boat.

Sent from my SM-G715U1 using Trawler Forum mobile app

 

[klee wyck]

This is from the Puget Sound Grand Banks Owners Asso. facebook page:

"Dear friends of Cats ‘N Dawgs,

It’s with great sadness that we share that our Grand Banks is now resting at the bottom of Glacier Bay. We are grateful to report all crew members are safe and healthy.

On July 1st CND was headed up Muir inlet to explore the beauty of Glacier Bay. While setting anchor, an unexpected 6 knot current pushed CND into the rocks. The crew made a valiant effort to secure the boat with both a front and rear anchor, but Mother Nature was too strong and the rocks breached a hole in the bottom of the hull by tearing off starboard stabilizer. Fortunately there was a coast guard helicopter training in the area and they were able to get our crew back to Juneau.

We are sure you all have questions and want to have more details but we’d like to ask for some time as we recover privately. We are still in shock and are trying to come to terms with what happened.

We have so many fond memories on our second home, CND, and she will be missed. We appreciate your love and support and will reach out again soon.

Rest in love CND!

The Padgett and McMahan Families"


Regards,
Scott

Not trying to be critical here, just trying to understand and learn….
What do others think of the part of this FB post that says “an unexpected six knot current push CND into the rocks”

Would you not expect to see that kind of current as you ‘read the water’ preparing to anchor? What can be unexpected with regard to a six knot current? That water is moving pretty fast…..

 

[SteveK]

Not trying to be critical here, just trying to understand and learn….
What do others think of the part of this FB post that says “an unexpected six knot current push CND into the rocks”

Would you not expect to see that kind of current as you ‘read the water’ preparing to anchor? What can be unexpected with regard to a six knot current? That water is moving pretty fast…..

Glacier Bay has a tidal swing of up to 25 feet, making awareness of tides crucial to boaters and kayakers

I suppose one can enter on slack, look around and be caught off guard.
https://www.nps.gov/glba/planyourvisit/tides.htm

 

[DDW]

Ah, OK, there you have it. So it would be really interesting to understand how they were installed.

In a previously referenced article, the same boat snagged a rock in Foggy bay, damaging a stabilizer and breaching the hull, high volume pumps saved the boat which was barged back to Seattle for repair. So the stabilizers on this boat are a multiple offender. Also, owners seem to have trouble avoiding rocks.

 

[GoneFarrell]

For those of us that were involved with on the job safety programs whether civilian or armed forces, there are several safety 101 reminders. The most straightforward? The sinking resulted from an unsafe act or practice. Even the owner says the same.

I agree. There were other/safer options available: explore the bay with the rib, not anchor in a poorly charted glacial estuary. Interesting that its second time for this boat hitting stuff with a fin.

I love exploring the nooks and crannies here and in BC, but I'm pretty careful about how I do that, having been through a couple anchor drag events in squalls.

 

[twistedtree]

In a previously referenced article, the same boat snagged a rock in Foggy bay, damaging a stabilizer and breaching the hull, high volume pumps saved the boat which was barged back to Seattle for repair. So the stabilizers on this boat are a multiple offender. Also, owners seem to have trouble avoiding rocks.

Yup, that really calls into question the whole installation.

 

[DDW]

I'd have thought that stabilizers would be designed so that the shaft would fail before the hull and outside of it. You'd loose the blade but wouldn't sink. I'd also have thought that the shaft would go only about half way down the blade which would allow the tip to get a bit crushed and damaged without losing the whole thing. However "graceful degradation" does not seem to figure large in a lot of engineer's thinking.

 

[twistedtree]

I'd have thought that stabilizers would be designed so that the shaft would fail before the hull and outside of it. You'd loose the blade but wouldn't sink. I'd also have thought that the shaft would go only about half way down the blade which would allow the tip to get a bit crushed and damaged without losing the whole thing. However "graceful degradation" does not seem to figure large in a lot of engineer's thinking.

That's exactly how ABTs are designed, and I expect Naiads too. That's why I'm so suspicious of the installation.


With Naiads, I think it's pretty easy to end up with a weak installation and/or one that becomes weak over time. The actuator footprint is pretty small, and they relay on a mahogany block to increase the footprint against the hull to distribute load. But the hull, wood block, and actuator are through bolted in a sandwich at the smaller radius of the actuator, leaving the block and it's attachment to the hull to do the real work. As a result, strength is highly dependent on how well the block is glassed to the hull. I have seen installations where it's not glassed in at all, but just epoxied to the hull.


With ABTs, the footprint of the actuator is much larger and serves the purpose of the wood block in distributing the load. But it does it with steel, and the sandwiching through bolting is done at the outer radius. So it essentially creates a massive hull reinforcement in and of itself. It's pretty foolproof, as long as the hull is strong enough, and of course any installation is dependent on that.

 

[tiltrider1]

I have heard of boats striking rocks with the fin and sinking. I have never seen pictures of thE installations so I have no idea why this sometimes happens. Most the time I see a boat with the fin gone and a bent shaft.

 

[Retriever]

I have heard of boats striking rocks with the fin and sinking. I have never seen pictures of thE installations so I have no idea why this sometimes happens. Most the time I see a boat with the fin gone and a bent shaft.

About a decade ago I overheard a mayday from a fairly new 58' Ocean Alexander near Petersburg. They'd struck a rock with a fin and were taking on water. USCG sent two helicopters, dropped them pumps, and they made it to Petersburg where they hauled out. I visited with the owner later that night and saw the damage. The fins were Keypower, factory installed, and the hull was cracked where the actuator was. The short term repair in Petersburg was to cut the entire damaged area out and install a patch. The owner ran the boat that way (with just one fin) the rest of the summer, then had a proper repair done in Seattle during the winter.

I know lots more boat owners who have hit fins on rocks, and in the vast majority of cases the damage is confined to the fin itself. Very occasionally I've heard about damage to stabilizer shafts or bearings. Damage that causes flooding seems quite rare, especially on full displacement boats (beefier construction, slower speeds maybe?).

 

[tiltrider1]

Sam, your experience appears to be similar to mine. It would have been interesting to see the installation on that OA 58. On my OA 54 I have a 2' square block that is 2 inches thick glassed in to spread the load of the fin. Not saying that a 10 kt impact couldn't break the hull just that a lesser installation would be more vulnerable.

 

[Portage_Bay]

I've seen two boats on the hard with huge holes from fins hitting rocks. A Nordhaven and a KK42. The owner of the Nordhaven was not around so I could only look at the damage. I did get to talk with the owner of the KK 42. He'd hit at cruise speed a pinnacle. In other words a steeply sloped rock.

Just guess here, assuming on both boats the stabilizers were properly installed, the fin shaft built and installed such that the fin should sheer off with striking a rock. Perhaps the shape of the underwater rock has something to do with the damage. If the rock surface is relatively parallel to the keel and deep enough to not strike the bottom of the boat then the fin should shear off with minimal damage to the hull. If the rock in the direction of travel is sloped up at just the wrong angle then the force on the fin might not be perpinduclar to the fin shaft and could tend to drive the fin and shaft upwards before the shaft fails. Similar to what would happen should a boat in big seas be "dropped" onto a rock at the bottom of the swell. Yes, I know, big swells and shallow rocks..... Just a mental image to visualize the effect of a more vertical force on the fin and shaft.

The two boats I've seen holed by fin damage, the damaged boat in this thread and failures on two fin equipped boats on deliveries I've done and I'm not a fan of fins. Great when they work, but a potential nightmare when they fail.

Sent from my SM-T500 using Trawler Forum mobile app

 

[Mako]

When I was a younger:
We once forgot to put the drain plug back in the boat we took on a dive trip Florida keys!
Later in the day we wondered why we where sitting so low in the water...

Wow, what a meatball , I would never do something like that...

Ahem, took my brothers 20nm out to fish the Pelican Flats and was wondering why the boat was sitting so low towards the end of day. Turns out there was a BIG crack in the hose exiting the bait tank pump. I had been pumping 2 gallons of water into my bilge for every 1 into the bait box. Bilge pump was manual only with no high-water alarm.

Real rocket scientist - Ha!

 

[soin2la]

I've seen two boats on the hard with huge holes from fins hitting rocks. A Nordhaven and a KK42. The owner of the Nordhaven was not around so I could only look at the damage. I did get to talk with the owner of the KK 42. He'd hit at cruise speed a pinnacle. In other words a steeply sloped rock.

These tales of folks tangling with rocks, especially where fins are hitting, is just pure inattention.

It’s like the guy who drives into an underground lot, forgetting he has the camper on the back.

But more than that, how could that KK 42 be travelling at cruising speed, so close to a “pinnacle”? I mean, how far beyond the sides or bottom does a stabilizer extend?

They could just as easily have powered right up on top of that thing.


And....

Great when they work, but a potential nightmare when they fail.

None of what I have read here, is the fault of, or result of, failing stabilizers

 

[sunchaser]

Sointula
Your point is well taken. Avoid cruising near or anchoring on a rock seems prudent. Page 262 of the Douglas Hemingway guide should be believed, showing a picture of a boat on a rock in - Muir Inlet?

 

[twistedtree]

These tales of folks tangling with rocks, especially where fins are hitting, is just pure inattention.

It’s like the guy who drives into an underground lot, forgetting he has the camper on the back.

But more than that, how could that KK 42 be travelling at cruising speed, so close to a “pinnacle”? I mean, how far beyond the sides or bottom does a stabilizer extend?

They could just as easily powered right up on top of that thing.


And....


None of what I have read here, is the fault of, or result of, failing stabilizers

Good point. The boat sank because of where and how it was being operated, not because the fins jumped off the boat. As a result of the boat operation, the fins are what gave way first. In the absence of fins, it probably would have been some other part of the boat. Getting hammered on rocks is unlikely to end well for any boat.



Now I think we all have to admit that having fins increases chances of clipping something where you might otherwise escape disaster. But if you just graze a rock, call yourself luck, not wise that you didn't have fins. And on reflection, examine why and how you ended up so close to that rock, not whether or not you should have fins.

 

[Portage_Bay]

These tales of folks tangling with rocks, especially where fins are hitting, is just pure inattention.



It’s like the guy who drives into an underground lot, forgetting he has the camper on the back.



But more than that, how could that KK 42 be travelling at cruising speed, so close to a “pinnacle”? I mean, how far beyond the sides or bottom does a stabilizer extend?



They could just as easily powered right up on top of that thing.





And....





None of what I have read here, is the fault of, or result of, failing stabilizers

Regarding the KK 42 fin damage I agree with your point about operator error. In speaking with the owner that's exactly what it was, operator error. The hazard mark is on the north side of pinnacle, he approached from the south. Either incorrectly reading the chart or failing to consult the chart at all.

I was trying to reason out how / why fins could be driven into the hull when they are designed to shear off. Not passing responsibility for the hull damge off to the fins or fin designers.

A fuller explaination regarding the two fin stabilzer failures I mentioned.

One was on an 85' boat at sea in moderately heavy weather. The Niad system went berzerk. We never did figure out what went wrong. Fins turning the wrong direction and or sticking in full or near full deflection are not a good thing at all. A real PITA as we rolled beam to seas securing the fins. It also happened to the owner during close quarters maneuvering. Essentially an additional rudder he had no control over.

The other was on a 45' boat in what was for that boat heavy seas. They began to fail, the first signal of trouble being a dry bearing squeal that sent me to the engine room to locate the source of the sound. Upon locating the sound at the fin drive mechanisim I noticed in addition to the failing bearing the hull flexing at the mount. Again no joy in rolling in beam seas as we secured the system.

Taken togehter, failure of fins to shear off in some circumstance and the system failures I have personal experience with I remain no fan of fins.

I've contributed enough to the thread drift. If we want to continue the discussion of fin stabilizers I suggest a new thread. This thread is about the boat sinking in Glacier Bay.

Sent from my SM-T500 using Trawler Forum mobile app

 

[gc9773]

They say a person has a 50/50 chance of making it 50 feet to shore in the cold water

When I was working aboard ship in the Pacific Northwest, our survival tables gave 30 minutes in that water...