Unsinkable boats realy?

We have an unsinkable boat ,A US Navy 50 ft Utility.
Open boat , looks like like a big yacht club launch

One design consideration was the boat which services carriers with deep draft is the boat would not swamp when filled with water.

Would be hard making 153 phone calls to relatives because of a big wave!

Second was it could be bulldozed off the carrier deck should the carrier be hit , to serve as a lifeboat.

Only problem is sufficient foam flotation takes a HUGE amount of room out of the vessels volume.
While a Boston Whaler or even a 50 ft launch could float with a 4ftx4ft hole , the more usual use of a collision bulkhead and compartment sub division works too.

It can be done , our 33ft sail boat has a collision bulkhead and 2 water tight doors.

Not too expensive , and not very heavy in aluminum. Bilge pumping does get a bit more complex.

 

I think the term "unsinkable" is misrepresented (and abused).

First define "unsinkable".

The problem with "laws" are that they now replaced common sense as if a law can think and apply reason. I have yet to hear those making laws taking responsibility for their flaws.

 

A good effort, but maybe not foolproof

eg.
"Toilet is behind a watertight bulkhead 2 inches above the waterline."

So, can the door withstand half a ton of water, from either side ?

If he got holed through the toilet area of the hull, does he have substantial dogs to hold the door closed against water inside the head area, or just the usual little lock fittings for privacy ?

His comments " ...... I sail with less anxiety now when plowing through heaving seas at 6 knots at night in mid-ocean." may not be founded on sound engineering principles.

 

Looks like the Australian buoyancy requirements only apply to boats under 6m in length, with sailboats, canoes/kayaks and various other types of boats exempt. Also air chambers can be used if buoyancy is assessed with the two largest air chambers flooded. Several different standards can be used to assess buoyancy including ABYC (very similar to the USCG standards) and ISO.
http://www.anzsbeg.com.au/files/2613/2095/8835/ABP_Ed_4.pdf
http://www.anzsbeg.com.au/boating-safely/australian-builders-plate/

 

positive flotation can be overcome enough heavier than water items attached to the boat, like an outboard, anchor and chain, batteries, tool boxes, fishing sinkers and of course treasure chests full of gold.

Just saying.

I stopped by the MacGregor dealership in Marin, CA and the guy said he once installed 6 batteries in one (plus outboard) and I'd wonder if that boat would then sink if flooded. I'd expect whatever the batts were for were also heavier than water.

I think any 'unsinkable' plan needs to include emergency heavy object ejection.


IIRC the only Brit sub ever captured by Germans in WW2 surrendered to a floatplane after becoming disabled on the seabed and releasing its keel ballast.

IMO, ANY keelboat for anything but closely supervised racing should have keel release provision, even if that leaves the boat floundering on its side. Lot easier to spot 30' of white fiberglass and metal buy
eye or radar than a couple heads bobbing in the waves.



In addition to inflatable life rafts for use OUTSIDE the boat, how about a system that inflates some big bags INSIDE the boat. It would be basically a large trash bag and a CO2 or something non-flammable. Multiple units depending on boat size, and different ways to activate: manually, when it senses 3' of water depth, etc.

 

Where I go boating there is no one around to help me if I get into trouble and they could only get to me by helicopter if I could contact the rescue services. Why would I not want all of the saftey and self help appliances I can carry so I can make it back to my secluded boat ramp.

There must be very good reasons why Aussies want to buy NZ unsinkable boats for their patrol work.

 

The reason to make everything compolsory is a wonderful way to create a business income.

 

Knowing my luck I would be the one in 3 months. Bloody hard to swim without legs to.

 

Tom barcrusher have a factory in melbourne, I would say thats how they won the contract. Plus over here work doesn't stop every time a sheep truck goes past.

 

I think a lot of standards are based on the uscg requirements. The rules are good and the 6 mt limit covers most of the turkeys that get into trouble because they think the skippers ticket they spent all afternoon getting qualifies them to cross bars and take the family offshore. I must admit I am surprised at how many of you are against the idea.

 

Actually it is the other way around The USCG requirements were for the most part adopted from ABYC standards. ISO, Canada, Australia and other countries have adopted much of the ABYC standards and then altered them to fit their own needs. For instance in the Recreational Craft Directive (the EU standard taken directly from ISO) the test for level flotation is performed differently, but the results are the same.

The idea behind flotation, whether it is level flotation, or Basic (the boat just floats with some part of the boat out of the water), is to provide a platform for people to be in, or hang onto. A capsized or swamped boat is far easier to find than a head sticking out of the water. Additionally if the boat floats level the people can stay in the boat and actually have some part of their body, the upper torso, out of the water reducing hypothermia. Some boats achieve this particularly well, such as Boston Whaler. On their outboard models the powerhead is still out of the water when the boat is swamped and the engine can be started and the boat gotten underway

As has been said, somewhere around 22 to 26 feet on a monohull boat this becomes impractical because of the interior volume of the boat and the amount of load it can carry, so above that length it is more practical to depend on watertight bulkheads and hatches, and other techniques.

And we regulators do make mistakes and hopefully we get them corrected eventually. Unfortunately it is actually harder to get rid of a regulation than it is to enact one, even though that isn't an easy process either. Contrary to popular myth regulators (including the EPA and IRS) cannot make regulations by fiat. I could go into the whole process at length but it would bore you silly.

PS: most boating fatalities are cause by falls overboard or capsizing, both resulting in people going into the water. Wear your lifejacket!

 

life jackets have to be worn here in boats under 5 mt or when alone or crossing bars.
As far as I know the rule is for level flotation. Foam under the gunnel. I know someone with a fifty foot wetliner . He does not have to carry a life raft because the boat has positive flotation.

 

I became interested in the development of the USCG load and floatation requirements in the early 1970's when John Gardner was writing about proposed load and floatation requirements in National Fisherman. My recollection is that ABYC was heavily involved in the formulation of the regulations. However I don't think that before the USCG started the process of developing the requirements ABYC had any floatation standards other than what is now called "basic floatation".

 

I am surprised no one has come up with a large airbag system like a car that could be deployed throughout the hull in an emergency. A emergency panel located somewhere with the switchs to set them off.

 

If an unconscious person is in the space when the airbag deploys, then what? Look, floatation requirements for small craft exist and work. Once again, there's a practical limit for these approaches, so you move to the next practical approach, which is compartmentalization. It's not a matter of law, so much as simply physics and practicality. We could go way over the top, but costs and practicality will come to play. For example, a ballistic recovery chute on all small aircraft could solve a lot of mishaps, but they cost a lot a bit, increase operational costs (inspections, rocket replacement, etc.) and they are only practical on small craft, though with some vision and a large array of really really big chutes, you might be able to save a loaded C-130 that's slowed to stall speed. God help what's under it when it touches down though.

It would be nice if we could venture into dangerous positions (unnatural human environments) and have little to know fear, but then folks would be clamoring for a device, that can sense when you're about to die and alert a standby helicopter, that'll rush you the a waiting trauma team, to deal with your tweeted ahead situation.