Deep Diving 108 feet w/ a single AL 80 (Air.) No redundancy.

Went back to my logs from Blackbeard's in the Bahamas.
118' for 34 minute
121' for 34 minute
and a few more over 100' with 40+ minute run times.
All done on a singe AL80

 

11L tank for a 30m non deco dive is plentiful if you have relatively good gas consumption.
I won't even blink an eye if someone suggesting to me!

 

Now, hell no.....

With that said the first time i went deep was 103 with a AL 80.... being young and dumb as I was back then.

 

I've gone to 140' on an 80. I'd do it again for fun. But with students, as an instructor, I want more air just in case.

 

If an aluminum 80 was all that's to be had then that's what you dive - NDL and gas volume aside no matter the tank size, it's a recreational dive...... I'd want you to be aware and have a plan for a low pressure hose failure but we should always be aware and have a plan for that...

I wouldn't even say there's "more room for error" with a bigger tank - every little bit counts maybe but at 1000psi in an 80 verses a hp120, you got 9cf more gas.

Is it worth diving that with an 80? I'd be looking for a set of doubles personally.

 

With good vis, no risk of fouling, no responsibility, no deco and a clear path to the surface I wouldn’t have a problem with it. But there’s very few wreck dives at 108 feet in my area that would fit that plan.

 

Hello. Very nice account.
Thanks.
Cheers.

 

At the depth you mentioned 108 ft which is approximately 33m I probably would not do this on air today, although I have done deeper dives on an AL80 years ago but with very short time at that depth in the Red Sea off Jeddah when I lived in Saudi back in the 80s/90s

Today I rarely dive air unless I have shallow dives planned (less than 18m), and I always carry a pony / stage with EAN50.

We have several dive sites that at 30m and plenty divers do this on air using a single AL80, whereas I prefer EAN34 for that additional bottom time (square profile dive) and will switch to EAN50 at 21m on ascent. I've become more realistic about my own mortality as I've grown older. I usually surface with 80-90 bar in my AL80 and use around 40-50 bar in the AL30 pony.

 

Ok, so now we are saying NDL divers need more contingency than cave divers? Anyone can be as cautious is they choose for themselves, but this is a bit over the top. Start the ascent at 1500, sure depending on your SAC that may be prudent. I would probably wait for about 1000, but would likely hit NDL first. All that said, I haven't dove to any significant depth with a single in years.

 

I wouldn’t blink at this sort of dive either. Any little problem at depth will become a big problem pretty fast, the margin isn’t really there, and a buddy isn’t giving you much more either and you might be safer alone. I would feel better about it with a pony and / or a steel 100 but I’ve done it before and will do it again if the reward seems worth the risk.