equipment configuration

[MikeFerrara]

I just started reading this thread and I can't believe what risk-takers some people are. Going to 200' on air! Doing deco recreational dives on one tank! Not allowing any room for problems in their dive planning! Heck, doing deco recreational dives at all. Why??? Sure, you might get away with it, but this type of activity will catch up to you sooner or later. Mother nature's lessons can be harsh.

Why?

Because the profiles required to dive the wrecks and caves that we dive require staged decompression. We do more than just get away with it. We don't do it on single tanks or air though.

Aside from that, anytime you get compressed you must get decompressed.

 

[ew1usnr]

The US Navy Standard Air Decompression Table goes to 190-feet. The table continues to 300-feet under the heading "Exceptional Exposure". They allow a 5-minute "bounce dive" to 200-feet with a one minute decompression at ten feet.

Reference: http://www.coralspringsscuba.com/usn/Chap09.pdf

While not recommended, this could be accomplished on a single 80.

 

[cornfed]

While not recommended, this could be accomplished on a single 80.

The list of achievable yet bad ideas is quite long.

 

[ew1usnr]

The list of achievable yet bad ideas is quite long.

That's a quotable quote.

The original post asked for thoughts on equipment configurations. Following Pug's lead, I would bring a little bit of hardware on the trip and rig a couple of tanks as side-mount bottles. It would only take a couple of minutes. Then I could wear one 80 on my back and have the option of wearing one or two stage bottles at my side, depending on the depth of the dive.

I've dove in fresh water with that type of set-up with no problem. Sea water would be a little different, but after a test dive or two I'd be ready to go. Independent back mounts with bands (assembled on-site) would be another option, but I would have to buy more equipment and it seems (to me) less flexible and more of a complication than leaving the tanks separate.

 

[jo8243]

"Exceeding 130 feet without propper training and equipment is just plain stupid" -- is probably more correct. However that is also a message which requires quite some more explanation (what is "propper training and equipment"??), and as such may not work welll in the PADI "Adventures in diving" context (which is to introduce various areas of diving, without doing into "depth" with each area - pun intended).

Actually, the direct quote on p.71 in the PADI adventures book is "Exceeding 130 feet on a single cylinder and using recreational scuba equipment isn't technical diving -- it's just being stupid."

Pretty good summary I think...

 

[Diver0001]

<snip>

With a moderate SAC and a big tank (as mentioned, I drag around an 18 litre 200 bar thing) <snip>

I'm curious why you would choose for this instead of a double-10. Care to go in to that?

R..

 

[DFC5343]

I did a deco dive in Cabo to 250 on a single 80. My bottom time was 10 minutes and 3 stops, 30 for 1min., 20 for 4 mins. and 10 for 7 mins. It can be done but under the most extreme dive planning and related experience. I wouldn't suggest such a dive profile to any diver using SCUBA.

 

[nyresq]

what is your sac? are you sure you're breathing??

how fast did you get to bottom and how fast did you come up from 250 feet???

10 minutes at 250 feet on a single 80?

taste death live life huh?
thats way over the edge for me....

 

[DFC5343]

Pretty much a freefall off lands end so getting there was easy. Ascent was the long part. I still had air left as well.

 

[RiverRat]

Hey I'm only a rec diver.....but what about taking 10 or 20 spare airs instead of a pony? Just kidding of course.....but this post is giving me the willies.....
beche de mer be safe man, don't do anything crazy dude!