What defines technical diving - and how to get there?

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JeffG

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highflowdiver

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guess you missed the second half of my post.

FWIW, no, I've never dived a quarry, though I don't see why I would treat it any differently than an OW ocean dive.

Come to the midwest and I would be happy to take you quarry
diving. You would then notice that a quarry is much more
benign than the ocean. You don't have to worry about:
getting blown out to sea, tide, surge, current, dangerous
animals, falling to thousands of feet deep,salt eating up
O rings, getting hung up in nets, fishing line,etc. Then you might realize, hmmm, breathing a side bottle here is a piece of cake.
Kal
 

Bismark

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No. We just don't believe he dives.

Unless X-Box has a new diving game that I am not aware of...........

Jeff, you game for a 15 min bottom time at 350' with nothing other than back gas and some interesting deco gases? Maybe we should try it with a goat first........
 

Blackwood

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Unless X-Box has a new diving game that I am not aware of...........

Jeff, you game for a 15 min bottom time at 350' with nothing other than back gas and some interesting deco gases? Maybe we should try it with a goat first........

Let's see, I'm assuming at 350 he'll be on 10/70, so theoretically he should be on travel gas for the first 30 feet or so.

I'll also assume he's really motoring it down there...

60 FPM from 30 to 350 => 5minutes * 7ATM * .7CFM/ATM = 25CF of backgas for descent

350 for 15 => 15minutes * 11.5ATM * .7CFM/ATM = 120CF of backgas at depth

First switch at 200 (which despite his claim in post 43 is at 1.4 not 1.6 ZOMG SOMETHING GUE DOES IS RIGHT) assuming he doesn't do any deep stops => 5minutes * 9.5ATM * .7CFM/ATM = 33CF of backgas to the first bottle.

From his posts in other threads, I don't think he believes in maintaining a reserve for his dive partners. If so, he could justify doing that dive on double 95s with no stages.

Off the cuff, 'Rock Bottom' for that profile would be about 140CF (making even double 130s inadequate), so personally: hell no.


edit: and since he's using Vplanner, that backgas at depth figure will be reduced by about 1/3 (I believe it would count the descent towards the 15 minutes).
 

JeffG

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Unless X-Box has a new diving game that I am not aware of...........

Jeff, you game for a 15 min bottom time at 350' with nothing other than back gas and some interesting deco gases? Maybe we should try it with a goat first........

Stage bottle, lots of back gas (dual 130's) and its doable. (plus 3 deco bottles, 120/70/20)

The Athel Viking is around 300ft and open circuit has been used on the Britannic (400ft). But a rebreather starts looking better at that depth.

(Note: I was the support diver for the Athel Viking dives)
 

nereas

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Let's see, I'm assuming at 350 he'll be on 10/70, so theoretically he should be on travel gas for the first 30 feet or so.

I'll also assume he's really motoring it down there...

60 FPM from 30 to 350 => 5minutes * 7ATM * .7CFM/ATM = 25CF of backgas for descent

350 for 15 => 15minutes * 11.5ATM * .7CFM/ATM = 120CF of backgas at depth

First switch at 200 (which despite his claim in post 43 is at 1.4 not 1.6 ZOMG SOMETHING GUE DOES IS RIGHT) assuming he doesn't do any deep stops => 5minutes * 9.5ATM * .7CFM/ATM = 33CF of backgas to the first bottle.

From his posts in other threads, I don't think he believes in maintaining a reserve for his dive partners. If so, he could justify doing that dive on double 95s with no stages.

Off the cuff, 'Rock Bottom' for that profile would be about 140CF (making even double 130s inadequate), so personally: hell no.

I stopped doing long-hand dive plans a long time ago, when V-Planner was published. It does a really good job, and it's a lot more accurate than anything you yourself can do with a pencil. Plus it does not make mistakes.
 

JeffG

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"This message is hidden because JeffG is on your ignore list. "

Here is a really good way to clean up a lot of meaningless crap.

<snicker>
 
https://www.shearwater.com/products/peregrine/

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