horizontal decent

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Hey Cadet,
Head first kicking is only necessary in very strong current while drifting to hit a wreck. I descend like that anytime the surface is ripping unless I'm doing the superman off a descent line.
 
any thoughts on the speed of descent

30 ft/min ~ 100 + ft/min

include pro or cons with your thoughts

posissioning, NetDoc nailed it
 
head first and kicking is also useful when you drop something like a torch - yes experience talking, not advisable though!!

"Sky Diving" in a ripping current is the best, especially on a long drop in good viz....
 
I have finned to 200 without a problem before. I am not sure I see any reason not to, as long as your buddy is with you, why not?
 
and NAUI uses it as their max as well. 75fpm!!!

While there are no reasons given, I have heard that the onset of narcosis can be premature on a quick descent. I have no data or study to prove this, as I have only heard it from one doctor. Also the effects of inertia will be present, possibly driving you into the bottom if you try to slow at the last minute.

While I have gone considerably faster than this on occasion (free descent in a ripping current trying to find a wreck) I do not see the need to "conserve air" by consuming it. Relaxed ALWAYS saves more air than excersize. You would probably conserve more air by chilling out and letting gravity do it's thing, than by exerting yourself to hasten things along. Less work ALWAYS means more air!!!
 
Well at least its worth knowing and using various techniques, thanks for answering my questions. I will probably still race to the bottom when not leading dives, but I will definately give this horizontal decent business a try.
 
my chase for a torch the problem was I was pushing it to catch the torch so ended up hyper ventilating - took a while to get myself back together after that....
 
Jonathan once bubbled...
my chase for a torch the problem was I was pushing it to catch the torch so ended up hyper ventilating - took a while to get myself back together after that....

Did you at least catch it? Or did you get yourself all worked up over nothing?
 
NetDoc once bubbled...
and NAUI uses it as their max as well. 75fpm!!!

While there are no reasons given, I have heard that the onset of narcosis can be premature on a quick descent. I have no data or study to prove this, as I have only heard it from one doctor. Also the effects of inertia will be present, possibly driving you into the bottom if you try to slow at the last minute.

I can attest to the onset of narcosis with a rapid descent.
say on a 200 ft dive on air [i know, i know, don't start the air thing] at about 75 - 100 feet per minute narcosis hits my like a sledge hammer at 180 feet, [shallower is not a problem]
how ever a rapid descent does not bother my buddy at all.

now if we descend slow and steady i can stay quite a while with out having any obviouse symtoms of narcosis, however with my buddy the longer he stays at dapth the worse he gets.

the inertia thing could also be a factor if there is a bottom. i do some blue water diving, [dives where you are in the middle of the ocean and there is no bottom] this diving is for a specific reason and we descend fairly quickly - about 100 feet/ min. as timing is of the essence

in one perticular case i was to meet my buddy at 300 feet, he was on a rebreather, and went early to perform his task, i then descended down as the videoagrapher, my plan was to shoot to the bottom and start hitting the brakes when i saw his lights as i was videoing on the way down. well guess what, he was hanging out there with out his light on, just drifting along with the line, well i blew right by him. seeing him i hit the brakes and it took me about 50 feet to stop. if there had been a bottom i would have been planted deep in it. [wel not really, as i would have used a different plan]. now i mount a depth gauge onto the video housing for refference.
 
AquaTec once bubbled...
any thoughts on the speed of descent

30 ft/min ~ 100 + ft/min

include pro or cons with your thoughts

posissioning, NetDoc nailed it


I usually descend about 100' per minute. It gets me on the wreck quickly. And I can still do it while staying horizontal. I stop at around 20' on the way down to do my equipment check, then a fast descent to the wreck.

I will however, use a slower descent rate when doing deep air dives, to avoid a rapid onset of narcosis.

And I definitely have to agree with Netdoc's top ten list.
 
https://www.shearwater.com/products/perdix-ai/
http://cavediveflorida.com/Rum_House.htm

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