>Dave, you need to stop posting.  I don't have enough time to spend all
>of it debunking this shit.


Then feel free to not bother. My system (which -guys-, is
-exactly- the same way most of us dive) works.


>First off, climbing a ladder with all of your cylinders attached to you
>after a long or deep dive is pretty stupid.  This sort of exertion
>immediately following an ascent is likely to induce a type 1 DCS hit,
>if you were anywhere near your ceiling upon surfacing.  This is what
>surface support and other team members are for.



On a NE salt water dive boat, the relality is if you dawdle at the ladder
you are going to get smacked up. We have no -support team-.
We cannot simply tread water at the side of a ladder heaving
10+ feet and unclip our stuff and hand it up. Sorry!



>Second, pony bottles of any type are a bad idea.  Putting a gas
>cylinder in a location that necessitates either using a long SPG hose,


(tucked under my chest strap where it bothers nobody..)


>where it is possible to have a second stage in any position on your
>body that might get confused with either of the back gas regulators,

Poseidons for mains, one over each shoulder and a -bagged-
Poseidon Odin with the pilot valve switched to surface for 02.
Hard to confuse 'em, eh?


>A gas should
>only ever be breathed from if you can make a one hundred percent
>positive identification without any sort of tactile aid.

See above. Different regs for different gases. Made deliberately
difficult to deploy (just bagged)


>Third, 190ish is not the borderline depth for air vs. trimix.  If you
>accept the liability imposed by the narcotic potential of air at
>anything approaching that depth, and the damage done to you by the
>nitrogen when decompressing, you need to take a serious look at your
>risk/benefit analysis.


Been there, done that. I'm diving trimix now all of the time.
Been in chanmers to 160 -many- times as an inside tender
for training dives. Been to 250 in the chamber a half-dozen
times for training. Know all about it. 190 would be my early-years
cutoff for air. Now it's more like 140.

Aint technology grand? BTW, I was diving mixed gas offshore
in 1977, so it's not rocket science.


>Better yet, quit diving and take up golf.

If I quit now, I'd still have more time in deco than you surelyhave
diving total. I do not mean this as a put-down at all. Far from
it. Of course that's easy when you are doing 1000'+ sat diving
where deco is measured in days. Remember the Westinghouse
Cachalot sat system? Take a look at the divers in the photos and
you'll see a certain smiling version of myself. Regardless of
those who poo-poo commercial experience, doing open ocean
saturation diving to those depths is a good way to learn the
use of all available technologies. Locking out of a bell in a
helmet and rebreather is not kids stuff. Diving where a 80 foot/3
AGA bailout system gives an even dozen breaths if you screw your
umbilical is as complex as any cave diving. Using CCR-1000's
as bailout rigs and using all of the stuff that we were given was
a blast, but as demanding as -any- technical diving. I have the
advantage of a formal education in the technology (UT, Florida
Tech, 1977) as well as a formal education in hyperbaric physiology.
So, suffice it to say, I'm not quitting anytime soon.




I>Fourth, a 40 of oxygen filled to supply pressure (2015-2200 psi)
>contains more than enough gas to deco out on for that dive, unless you
>are doing ridiculous bottom times, in which case you should ask
>yourself if you can do two shorter dives instead of one long one, or
>you are doing a ridiculous deco for a given dive, or if your RMV is
>poor and you need to hit the gym.


Agreed. Actually I jam mine to about 3000 and am happy with it.



>Fifth, ignoring the possibility of being blown off the anchor line is a
>complete lack of foresight.  Carry all of your deco gas with you,
>unless you can guarantee you will be swimming back over it, such as is
>the case with caves, where you either come back to it or you die.



I don't cave dive. I have never been blown off a line and hope
never to be. My answer is that if I am, I'm probably dead anyhow.
I'm going to need to free-deco and without a EPIRB I'm sharkbait.
This is why I take the anchor line as seriously as an overhead environment.
It's my path to safety. Maybe I ought to carry an EPIRB. Hmmm.....Maybe.



>Sixth, closed circuit apparatus introduces additional complexity to the
>system in the form of electronics, and additional failure modes.

No shit, sherlock. You sound like a Halcyon advert. I've been diving
CCR-1000's since 1980. Had them to 1000' as saturation system
bailout rigs. Fighter airplanes introduce additional complexity too
and I manage to fly them. Shit, side mounts add additional complexity.
you need to be -trained-. The electronics are about 1/10 as complex as
a video camera. You ever see one of them just plain crap out? Even
in a housing?



>I could see using a rebreather for extremely long exposures which
>would require several stages of bottom mix, or when hypothermia
>is an issue in very cold water.

Thanks! You describe the mission profile perfectly!
That's why we use them.


Best regards,


Dave Sutton


--
Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'.
Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.

Navigate by Author: [Previous] [Next] [Author Search Index]
Navigate by Subject: [Previous] [Next] [Subject Search Index]

[Send Reply] [Send Message with New Topic]

[Search Selection] [Mailing List Home] [Home]