Mini scuba tanks instead of escape hatches?

[a64pilot]

Originally Posted by P3sailor

If not a certified scuba diver I wouldn't recommend the compact O2 bottle. Escape hatches aren't just there to enable escape from a swamped or overturned vessel. You've got to think about other emergencies that may arise, particularly fire! If you have no alternative escape route and a fire is preventing you from safely evacuating your vessel, you're screwed. Just saying.

Well you don’t carry an O2 bottle, because breathing O2 at a depth deeper than 20’ will kill you.
It’s compressed air, and even in a panic it has way more than a minute or two, I think 5 is conservative and that’s from practice, but just like any emergency procedure, if you expect to pull it off, you best practice it.
Besides all you Cat guys tell me two things, first you can’t sink and secondly there is a lot of trapped air in the hull. So where is the emergency? Where is the panic? I can imagine that opening an escape hatch could very quickly allow some of that trapped air to escape though.
Sit down collect yourself, think about it awhile and put the spare air in your mouth and exit slowly. You have 5 min to make it what 20 ft? If you can’t find the spare air, how are you going to find the hatches?

We don’t have a Cat, so I don’t have escape hatches, but in the event of a fire that the companionway is blocked, I’m climbing out of an overhead hatch. Wouldn’t it be the same in a Cat?

[redneckrob]

Originally Posted by a64pilot

I flew the AH-64 over the Yellow Sea, we carried “HEEDS” bottles on the left side of our survival vests and of course trained with them, HEEDS is of course an acronym, it stands for Helicopter Emergency Egress Device something, it’s been twenty years so I forgot.
Anyway these HEEDS bottles are nothing more than what Scuba divers call spare air, they are widely available, and you should train with them and they are refillable just like a Scuba tank.
Google found the HEEDS bottle, it’s just a spare air, don’t waste your money on a helicopter price https://www.aviationsurvival.com/-HE...e-17_p_35.html
There are a few differences with them over regular diving, to begin with nothing covers your nose, normally a mask does of course, but without a mask water gets in your nose when you breathe and that takes some getting used to.
Then of course you cannot have an auto inflating life vest or a regular buoyant one as it would just pin you to the top of the boat.

The Spare air bottle should give you about 5 min of air at very shallow depths and 5 min is a very long time. A major problem with suddenly being flipped over in a helicopter and I assume a boat is disorientation, we were trained to keep our left hand attached to the hand hold and use that as a reference to where you are, many People in training in the Dunker in NAS Jax where we received our initial training would head the wrong way and further trap themselves.
After Retirement I started cave diving and learned some more things there.

If were to have a Cat I’d want a couple of spare air bottles mounted in an obvious location, but I’d also want a light, just a decent dive flashlight would be fine, and a thin line that would lead me to the way out, this line could be attached to the roof so it would be out of the way which would of course become the floor. With just a little training a line can really be calming and ensure your heading the right way.

In cave diving a guy named Forrest Wilson invented the line arrow, it’s just a plastic triangle that attaches to the line and of course always points the way out, before the line arrow there were some deaths where people got confused and went deeper into the cave thinking they were headed out.
https://www.diverite.com/products/reels/line-arrow/
Forrest is an old guy now but still dives or was when I stopped anyway.

If you go with a spare air bottle, you need to at least become accustomed to breathing one underwater, and it can be the middle of the night of course. I would be very comfortable with a spare air myself with a light and a line.

I'll add from also having flown with HEEDs for 20 years that it's a lot more difficult than you might think to escape from something upside down under water even without any debris in the water. For naval aviation helo pilots on initial qualification and I think every 7 years afterward you had to do the 9D5 dunker which was a giant drum simulating a helicopter with 2 people strapped in the front and 6 strapped into seats in the back (you did a much easier small version every year). They put painted over goggles on you and dropped the trainer in the water, you had to wait for it to invert, and then everyone had to go out the door they specified in the brief (you did it 4 or 5 times to practice every exit). On probably every third ride they either had to have the safety diver pull someone out or they pulled the whole ride out of the water because someone got confused about where they were and became fixated on exiting out a non-exit. Add to that the fact that you are either going to get a significant amount of water in your sinuses if you maintained your reference points (which is a drowning sensation) or you're going to lose your reference point and end up trying to exit a blind corner if you try to hold your nose.

The saving grace in a cat is that almost certainly you'll have air left in each hull if you're inverted so you can stand up, get yourself to an escape hatch, and egress easily with no turns and keeping your hand on your reference point without having to turn upside down. If you have to egress through the saloon, you now have to make several underwater turns, have a half dozen blind corners to get stuck in, and may easily end up upside down, plus there's going to be crap floating everywhere. I would guess that 50% of untrained folks won't be able to do that successfully in warm water, 75%+ in cold, and the HEEDs bottle isn't going to really change those numbers much.

If you don't have escape hatches I'd say that you would stay that way because you think the chances of flipping while you're below don't warrant them. I wouldn't consider a HEEDs bottle to be a replacement in any way unless you accompanied it with serious egress training.

As an aside to address the scuba training issues, although I was a PADI open water certified diver and understood all the compressed air issues, they never mentioned any of those issues in HEEDs training. So either they didn't think they would be a problem, or they figured they'd just patch you up if you managed to survive and the air embolism was the least of your worries. Certainly everyone who ran the egress trainers and set up the training programs was a highly trained and experienced diver, so they weren't ignorant of the compressed air issues.

[MJH]

Originally Posted by Thetis

Our newly bought (second hand) Schionning does not have any escape hatches and we want to avoid building them in. We are considering the purchase of small scuba tanks, 0.5 or 1 l, to be used in an emergency situation (boat upside down and you need to escape out of one of the hulls). They could also be used for a quick inspection dive. Is there anybody out there who can share his/her experience with one of these tanks? Plus: There are some comparatively cheap Chinese ones on the market, which come with a manual pump. We cannot imagine that this will work. Again: Can you share your experience?

A number of years ago my neighbor flipped his Gemini one afternoon with his brother and elderly mother aboard in our local Puget Sound waters which are notoriously cold year round. He was thrown off the boat and his brother was able to swim out from the overturned hull...his mother was not and she remained inside. Rescue took well into the darkness (rescuers used a helicopter floodlight) and she was finally freed by them cutting through the hull, airlifted to the local hospital where she had a heart attack or stroke, can't remember which, but survived.

Offshore would have probably been a very different matter.

I don't sail a catamaran but think some well thought out escape plan would be in order to cover possibilities such as this.

~ ~ _/) ~ ~ MJH

[Lepke]

I'd worry about fire.

[Thetis]

Sorry Manateeman, I forgot to mention that we are acceptably experienced divers. Thanks for your warnings. I do agree with you that nobody should do this without any diving experience.

[Dsanduril]

As A64 alluded to above, I'm not sure I would even consider the main saloon door if I couldn't use/didn't have escape hatches. Once through the saloon door you then have to navigate underwater through the cockpit (which frequently has some type of enclosure) and out from under the bridgedeck. That puts you in the water outside the structure of the boat.

If I'm going to end up outside the structure then it seems the overhead (now underfoot) hatches in the hulls would be much easier. Most cats I've seen upside down float stern down, with a hatch forward possibly only 1-2' (30-60cm) underwater. Our forward hatches are also our largest, in order to get sailbags in and out. Wade forward, get down on knees, open hatch, then it is a short down and up to be outside the boat. That's breath-holding territory.

The advantage to escape hatches, in this scenario, is that you end up on the upturned bridgedeck in an area with "walls" created by the hulls. Any swimming scenario has you ending up outside the vessel's structure and at risk of drifting away before you can secure yourself and climb aboard.

Overall I don't like escape hatches, IMO they cause more problems than they solve, so I can understand not wanting to have them, but in the turtle event they sure would be nice to have.

[redneckrob]

Originally Posted by Dsanduril

As A64 alluded to above, I'm not sure I would even consider the main saloon door if I couldn't use/didn't have escape hatches. Once through the saloon door you then have to navigate underwater through the cockpit (which frequently has some type of enclosure) and out from under the bridgedeck. That puts you in the water outside the structure of the boat.

If I'm going to end up outside the structure then it seems the overhead (now underfoot) hatches in the hulls would be much easier. Most cats I've seen upside down float stern down, with a hatch forward possibly only 1-2' (30-60cm) underwater. Our forward hatches are also our largest, in order to get sailbags in and out. Wade forward, get down on knees, open hatch, then it is a short down and up to be outside the boat. That's breath-holding territory.

The advantage to escape hatches, in this scenario, is that you end up on the upturned bridgedeck in an area with "walls" created by the hulls. Any swimming scenario has you ending up outside the vessel's structure and at risk of drifting away before you can secure yourself and climb aboard.

Overall I don't like escape hatches, IMO they cause more problems than they solve, so I can understand not wanting to have them, but in the turtle event they sure would be nice to have.

I'd add that at least FP cat's have hardware to allow you to permanently mount a line that runs fore and aft at escape hatch level outside the hulls. I seldom see the line actually mounted, but it would sure be nice to have something to grab onto and pull yourself around on once you popped out that hatch!

[Dsanduril]

Yes. Our boat has escape hatches. I don't like them, but have not (yet) gone to the trouble of replacing them with something inset or a breakaway panel. Maybe one day.

On the bottom of the bridgedeck about 6" (15cm) from the hull joint there is a webbing jackline permanently installed (and since it is there, inspected each time we haul). It is possible to reach out through the hatch and clip in a harness before you crawl out the hatch. Never having had the boat upside down I've never really tried it.

[Thetis]

Thanks a lot, everyone, for your valuable pieces of advice. Overwhelming! Even if we are trained divers and have hatches big enough to escape in case of a fire, I'm impressed by the many points well worth thinking about.



Thetis

[Chuck Hawley]

After the loss of Andrew "Bart" Simpson in the run-up to the 34th America's Cup on SF Bay, i served on a committee that looked into making the America's Cup safer. We met for six days and came up with a long list of recommendations, many of which made it into the Louis Vuitton Cup and America's Cup. Of great interest was entrapment, either upside down in the dockpits or possibly held underwater by the trampoline.

(This was a long discussion with lots of great ideas, so I am not trying to be precise about the solution, but it's pretty germaine to what's being discussed.)

Originally, the crews used either the small Spare Air bottles, placed in critical locations around the boats, primarily in secure locations in the cockpits. I believe that all were the small size to start. As I recall, the teams migrated to having a Spare Air of either size on each sailor, and felt that having a flexible hose between the tank and the mouthpiece was superior. That way, the tank remained attached to the sailor at all times and could not be jarred loose, although the mouthpiece could be...

One of the other areas of improvement was both a system to "find" the sailors (really have them check-in electronically) after an accident, combined with a set of three very bright LEDs, which were intended to help locate a trapped sailor in the turbid water of the Bay. After much testing, I remember that the team came up with a bright orange LED as having the greatest conspicuity under water.

The ability to know how many sailors were "checked in" was vital after the experience with Bart. When Artemis folded up/capsized near Alcatraz, it became very difficult very quickly to find out how many sailors were missing, if any. There were two engineers on the boat in addition to the 11 crew, and the crew did not have obvious numbers or IDs on them. The RIBs swept in from Team Oracle and Artemis and began pulling sailors out of the water and placing them on the sole(s) of the RIBs. No one could tell how many sailors had actually been found and were safe. The first rescue diver from Team Oracle got to the accident site in about 90 seconds, donned his gear, and found that he had extremely poor visibility, was in a terribly dangerous diving environment, and didn't know how many sailors he was looking for.

Sorry for the long digression. The discussion of Spare Air reminded me of this terrible accident, and the techniques that were developed to make racing safer.

Cheers,

Chuck

[singlespeed]

My old Lagoon ('93) has escape hatches the sit about four inches above the waterline. In 11years of cruising full time, the escape hatches never leaks, no matter how bad the conditions. Weekly, I exercise each hatch if I am in a chop free anchorage. The hatch latches and hinges can easily corrode in place, making it almost impossible to open. Every time I haul, I put in a new gasket. Thorough cleaning of the gasket mating sufaces is critical for good, even adhesion.

[tekdiver]

Originally Posted by Thetis

Our newly bought (second hand) Schionning does not have any escape hatches and we want to avoid building them in. We are considering the purchase of small scuba tanks, 0.5 or 1 l, to be used in an emergency situation (boat upside down and you need to escape out of one of the hulls). They could also be used for a quick inspection dive. Is there anybody out there who can share his/her experience with one of these tanks? Plus: There are some comparatively cheap Chinese ones on the market, which come with a manual pump. We cannot imagine that this will work. Again: Can you share your experience?

I'll take a bite.
I'm a Scuba instructor and ex-dive Store owner.
We tired the mini bottles for an alternative to a pony bottle 40 Cubic ft vs around 60 breathes when your calm. I would say hell no. Students who were just trying to swim from the pool bottom to surface had issues with them. Add an emergency not sure which way is up or down not enough air plus care and maintenance. Mine were called spare air. I know folks have tried to use em when they clean hulls and with work like that get 20 - 30 breaths. Just my .02

[thinwater]

Dumb question. I don't know.


Egress from a flipped cat is NOT a time-critical emergency. It's not like a sinking helicopter where a few minutes are vital. They generally float upside down for a long time. First, you should take a few minutes to let things settle down and to orient yourself. Then, assuming it is your boat and you are familiar, hold you breath and swim out.


Dealing with breathing gear is going to make this very complicated for anyone who does not use the gear on a regular basis. You will probably be in pitch darkness and probably a bit paniced. This is a real problem!



Are there any known cases of someone not being able to escape an inverted cat? Or is this a made-up problem? I don't know. I am honestly curious.

[a64pilot]

There is nothing complex with spare air, place in mouth, breathe. That’s it.
Maybe hold your nose if you have the luxury, cause water up your nose and in your sinus isn’t pleasant, but I got over it, others can too.
So far as how long they last, I’m a Tri-mix diver and full cave, one of the things you compute for both is what your surface air consumption rate is, that way you can compute how much gas you will breathe at what depth your at, so you know how long each tank will last.
My SAC rate swimming is or was .67 cu ft per min. A spare air bottle holds 6 cu ft of air, and as we are not at depth we can pretty much ignore that, so a spare air bottle will last me almost 10 min.
But let’s say for whatever reason I’m panicked and breathing hard, it’s still going to last at least 3 min.

But as I said earlier, you guys tell me that they don’t sink, and there is plenty of air in the hull when your inverted, and I believe I’ve read accounts of people basically living in an upturned boat for long periods of time waiting on rescue, my assumption was that in heavy weather and seas that may overturn one, possibly being inside is more survivable?

But anyway, there ought not be any kind of panic emergency? Sit down, calm down and then take the spare air bottle and swim out?

Just me, but I wouldn’t knock large holes in my boat that could cause problems on their own, for a one in a million chance of something happening. I assume Cats turtling is about as likely as a mono rolling?

[FlyingScot]

Mine doesn't have them and I'm thankful for that.
As mentioned only once above, I'm going to open the now underwater hatch and swim out that way.