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  #1  
Old 09-08-2009, 01:19 PM
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Concepts for Self-righting Aluminum Center Console

Hello All:

I was thinking that a self-righting Centre Console, sportfishing boat would help save alot of lives.

I saw an example of this with the Coast Guards Rescue boats. Just wondering if anyone might have a sound grasp of the "necessary concepts" to achieve such a feature in something like the "ever popular" 20-29 Ft Center Console fishing boats we see being pulled up and down the highways every Holiday.

I look foward to all critical ideas, recommendations, suggestions and just plain babble... . . . . .
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Old 09-08-2009, 02:08 PM
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For a Coast Guard rescue boat, that must be able to go out and do its job in absolutely horrific conditions, self-righting makes sense.

However, I don't think it would be a useful feature on a typical 20 to 29 foot centre console fishboat.

From a technical standpoint, the large deckhouse needed to provide the buoyancy to self-right simply cannot be fitted to a centre console fishboat while maintaining the large, open cockpit/deck area that is the main reason why people buy these boats. You could do it, but it wouldn't be a centre console fishboat anymore.

But perhaps more importantly, a self-righting boat will be of absolutely no safety benefit whatsoever unless the captain and crew have seamanship to match. The level of seamanship needed to safely recover a self-righting Coast Guard rescue boat from capsize, applied to the existing centre console fishboats, would give those fishboats a virtually perfect safety record.

We can throw all the technology we want to at a problem, but to save lives, the people using that technology need to know how to use it....
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Old 09-08-2009, 03:56 PM
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Quote:
Originally Posted by marshmat View Post
But perhaps more importantly, a self-righting boat will be of absolutely no safety benefit whatsoever unless the captain and crew have seamanship to match. The level of seamanship needed to safely recover a self-righting Coast Guard rescue boat from capsize, applied to the existing centre console fishboats, would give those fishboats a virtually perfect safety record.
We can throw all the technology we want to at a problem, but to save lives, the people using that technology need to know how to use it....
If that was´nt a quote (and I assume it was your word), may I use it in the future?

Regards
Richard
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Old 09-08-2009, 09:47 PM
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ratrace2 ratrace2 is offline
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Marshmat,
Outstanding observation, learned point of view, and practical analysis, but a
practical concept can be pulled from your observation.

I think you understand the concept well; so it must be true that, " the large deckhouse needed to provide the buoyancy to self-right" is what I thought is the necessary element to achieve "self-righting.

All we need is something large enough to keep the bow buoyant; thus, allowing the stern to role up under the boat; thus, we just need enough volume on top of the console, or at, or about the hardtop height.

OR,

We can develop a hardtop and console with enough bouyant volume to bring the craft back 50%, and then let some sort of Ballast/keel configuration bring it back the other 50%.. . . . .. I like this idea...."a virtually perfect safety record".

After all, what fun is fishing if you don't live to tell about it???
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Old 09-08-2009, 11:58 PM
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Quote:
Originally Posted by apex1 View Post
If that was´nt a quote (and I assume it was your word), may I use it in the future?

Regards
Richard
Ditto!

Then again.....purely from a technical standpoint....
They do actually make self-inflating badders that are attached to the radar arch that will self right a centre console. They are quite common on RIB's
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Old 09-09-2009, 12:33 AM
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" "They do actually make self-inflating b[L]adders" [.]" I didn't know that. Hum?????

Why don't they make them mandatory equipment on 20-29' CC's
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Old 09-09-2009, 01:22 AM
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Oops - my mind works faster than my fingers!
Simple... $$$ ... and as Matt pointed out, there's no guarantee that it'd make them any safer in untrained hands
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Old 09-09-2009, 01:35 AM
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Bear in mind, also, that a roll-over of a 41' "roll-over" will create much damage, including stripping antenae and crew needs to be strapped in and main hatch cover dogged to even have a chance of survival. Also, crew do not always get through the forces involved nor the time submerged.
These little boats you consider, 20' to 29' center consoles, are typically outboard powered and will be not much more than something to hang on to if rolled, anyway. I, personally, feel that rolling over would suck and would strive to keep upright as an alternative.
Plenty of people die using "unsinkable" boats, BTW. Selling points aside, there is no substitute for learning, paying attention, and practicing seamanship as if your life depends on it.
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Old 09-09-2009, 01:37 AM
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..... and practicing seamanship as if your life depends on it.
Because it does....
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Old 09-09-2009, 01:43 AM
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"Why don't they make them mandatory equipment on 20-29' CC's" - More regs! Or we could just ban CCs, Mr. "Unsafe at Any Speed".
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Old 09-09-2009, 05:05 AM
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On a project I know... It was suggested to make the Centre console so voluminious that the boat were unstable in the upside down position. Testing showed that one tiny man (me, Norwegian winter... ). Could give the inverted boat a clasp on the arse, and it immedeately started to rigthen. The moment needed to start rigthetning was less than what was needed to lift myself up to breast height. Didn't look too bad either, strangely enough.

Added cost to the design this way is close to mimimal.

btw, if I recall correctly; the requirement for rescue boats is not self rightening, but that two men in water shall be able to righten the boat (SOLAS), So the boat shall at least be close to self rightening or equipped with a co2 inflatable rightening bag on the targa beam(?correct name??).
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Last edited by Knut Sand : 09-09-2009 at 05:10 AM. Reason: btw.....
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Old 09-09-2009, 09:49 AM
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Quote:
Originally Posted by apex1 View Post
If that was´nt a quote (and I assume it was your word), may I use it in the future?
Regards
Richard
Yes.
Quote:
Originally Posted by mark775
Bear in mind, also, that a roll-over of a 41' "roll-over" will create much damage, including stripping antenae and crew needs to be strapped in and main hatch cover dogged to even have a chance of survival. Also, crew do not always get through the forces involved nor the time submerged.
These little boats you consider, 20' to 29' center consoles, are typically outboard powered and will be not much more than something to hang on to if rolled, anyway. I, personally, feel that rolling over would suck and would strive to keep upright as an alternative.
Very true. If you roll a centre-console fishboat, the engine powerheads, console, all the electronics, batteries, etc. all get soaked. If you then get it back upright, you have something that sort-of floats, but certainly cannot move under its own power.
The Coast Guard RIBs that have those inflatable bags on the arch also have extensive modifications to the systems and the engines so that they will have at least some chance of being usable after a capsize. Needless to say, these boats cost more than double what civilian counterparts of similar size and performance go for.
Quote:
Originally Posted by ratrace2
so it must be true that, " the large deckhouse needed to provide the buoyancy to self-right" is what I thought is the necessary element to achieve "self-righting.
All we need is something large enough to keep the bow buoyant; thus, allowing the stern to role up under the boat; thus, we just need enough volume on top of the console, or at, or about the hardtop height.
OR,
We can develop a hardtop and console with enough bouyant volume to bring the craft back 50%, and then let some sort of Ballast/keel configuration bring it back the other 50%
Yes, you probably could. Again, though, I'm not sure people would buy it. The appeal of a CC fishboat is that the whole thing is open deck- you can walk all the way around the boat, with hip-high bulwarks in many cases. If you want this boat to self-right, you have to make it shed water and you have to give it a lot of superstructure volume- thus negating the centre console's main advantage. Ballast is not an option for buyers in this class- they want speed, lots of it.

The thing is, I have yet to hear about a centre-console fishboat capsize that was due to a design flaw in the boat itself. Every single one I've seen in the news has been attributed to poor seamanship- things like overloading, taking a boat farther out than it really ought to go, failure to keep bilge pumps clean and operational, allowing the boat to lie beam-on or stern-on to the seas, everyone running to one side to help net/photograph a fish (while the boat is beam-on to the seas).... and in an awful lot of cases, the survivors (if there are any) are plucked from the water in T-shirt and shorts, with the lifejackets still safely secured somewhere in the bow locker. Some people even try to leave the capsized boat and swim for shore- something any kid with a few years of swimming lessons can tell you is a definite Bad Idea.

As far as open boats go, I'll stick with the cruising catamaran approach to capsize: Don't flip it in the first place.
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  #13  
Old 09-09-2009, 10:28 AM
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Quote:
Originally Posted by Knut Sand View Post
On a project I know... It was suggested to make the Centre console so voluminious that the boat were unstable in the upside down position. Testing showed that one tiny man (me, Norwegian winter... ). Could give the inverted boat a clasp on the arse, and it immedeately started to rigthen. The moment needed to start rigthetning was less than what was needed to lift myself up to breast height. Didn't look too bad either, strangely enough.

Added cost to the design this way is close to mimimal.

btw, if I recall correctly; the requirement for rescue boats is not self rightening, but that two men in water shall be able to righten the boat (SOLAS), So the boat shall at least be close to self rightening or equipped with a co2 inflatable rightening bag on the targa beam(?correct name??).
Yes, this is kind of what I was thinking.. . . At least it would be a perfectly acceptable compromise.
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Old 09-09-2009, 12:00 PM
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This "rescue boat" you're talking about might be a life raft - if it deploys upside down, it can be righted before the stability chambers fill up with water. Speaking of forces that most don't imagine, in weather that causes a capsize, inflatable life raft can tumble with shredded or collapsed stability chambers trailing behind. There are those that have died from getting thrashed inside a cartwheeling raft.
About a RIB that the CG might use in a rescue; just last winter, kudos were received by a helicopter crew here for saving some hikers on a beach (Latitude 59.65N and Longitude -151.12W) who had a capsized boat...and crew of a CG rescue boat of the inflatable targa technology half-turtle alongside her, doubling the victim count needing rescue. What is the boat you are talking about doing in this weather?
Should wool clothes under a mustang suit be required to be worn, as well? A way to start a fire? Helmet, mouthpiece, steel-toed shoes, cup, confined space entry permit? I say, ban CCs entirely and be done with it.
Curious to see the, say, 25 footer that a guy could grab onto and pull right-side-up - let alone in the same **** that would capsize it.
Have fun with your self-righting plan. Please, tho, don't make me, one day, come and instill logic into some bureaucrat goofball about this.

Concepts for Self-righting Aluminum Center Console-2584882030_4b21887a93.jpg
Doesn't look like it could be too bad here, does it?

Concepts for Self-righting Aluminum Center Console-fern-harbor-sea-otter-30_glacier-bay-national-park-alaska.jpg
This witness, later interviewed, said that, in his opinion, Nebraska kids with cool, self-righting technology are still Nebraska kids (and lucky to be alive).
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Old 09-09-2009, 11:35 PM
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Having trained for, and experienced a self righting bladder deployment on a

Canadian CG Zodiac, I'd take a slew of self rescue gear before one of those

things. Several points to consider: you're not likely to get it running again

and if you do, you've got this bloody huge air sausage sticking out like a

sore thumb. You are no longer an asset but a liability now needing rescue.

Give me a PFD, dry suit, strobe, parachute flares, smoke cannisters, EPIRB

(Emergency Position Indicating Radio Beacon) and sealed marine VHF radio

and I'll see you back on shore. Better yet, don't get yourself in the position

of needing any of that gear in the first place! This is by far the best option.

You're kidding yourself if you think any of this gear is necessarily going to

save your sorry ass BUT you wouldn't catch me out in a nasty sea without
it.

-Tom
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