How do I do a 50m bounce?

[stevewirl]

im a search and recovery diver in ireland and have recovered many divers from deeper depths than they initally decided to go to .

do the course and if you havent already do the boyancy course .

diving deep is not hard . knowing what to do if somthing happens whilst deep or after being deep is the real learning curve . as surfaceing is not always an option .

do the course and then dive with someone who dives down there for a good few dives after the course .

 

[gorcio]

Before there was trimix, divers would dive to 250 ft or more all the time on air and just pay for it with narcosis and a huge deco obligation.

Some still do so. But it already is on the brink on getting OTOXed, and to me personally - it is just stupidity. Not the deep dive itself, but doing it on just air. As someone already pointed out ... buoyancy control, planning and training would help one stay safe. Still, for those who want, it is perfectly doable on air. With all the "blessings" that come along with narcosis, deco time etc. Just my 3 cents

 

[Damselfish]

"build up" dives have their place, but this isn't one of them.

 

[Meng_Tze]

Hallo fellow dive folk I have decided If done enough 40m dives I want to do a 50m dive with a bottom time of say 3-4 mins. How should I go about doing this I have not done any tech training yet so deco I dont know.

HMMM where can I start my search to do this???????

ps build up dives are my friends

How do you do it? Well, you go down to 50m and stay there for 3mins, then you go up. Of course if you want to come up knowing what to do and when, where to stop and how to avoid CF's.....training will help. If you just do this on your own...................you ARE on your own.


Look at it this way............going down is not the challenge...........coming up safely takes some knowledge and experience. Training is a good start.

 

[dkatchalov]

What are your motivations for this dive? BT of 3-4 mins seems pointless. You probably won't remember anything of those 3-4 mins anyway because you'll be narced out of your mind.

Also, why post this in the tech forum? Your dive has nothing in common with technical diving. If tech divers bounce dive they usually have a solid reason for doing so ("40m is not deep enough for me" is not a solid reason). They also have the adequate training, redundancy and planning in order to complete the dive safely.

This reminds me of an old thread where the OP wanted to do a 71m dive ASAP with < 10 dives under his belt. Search for a thread titled "Deep Deep Diver" or similar and see the response he got. I thought that concept was stupid and this thread falls in the same category IMHO.

Apart from that...

 

[lamont]

use 21/35, double tank, deco bottles and proper training and you can stay down there for 30 minutes instead of 3 minutes do it safely and enjoy and remember it, and continue doing it for years without getting hurt. you're placing your life at risk doing bounce dives like that just to get a big number for depth in your dive log.

here's the most recent fatality we've head doing deep air bounce diving in 2007:

http://www.scubaboard.com/forums/accidents-incidents/166222-lost-diver-puget-sound.html

here's the previous one in 2003:

NewsLibrary.com - newspaper archive, clipping service - newspapers and other news sources

i believe this is a third one from 2000:

SEARCH FOR LOST DIVER OFF ALKI BEACH CONTINUES INCIDENT AGAIN RAISES CONTROVERSY ABOUT LIMITS ON FIRE DEPARTMENT.(News) - Seattle Post-Intelligencer (Seattle, WA) - HighBeam Research

the practice that you're asking about does, in fact, have a body count associated with it.

 

[vshearer]

Death - Wikipedia, the free encyclopedia

 

[dkatchalov]

To the OP, this is the thread I referred to in my previous post: http://www.scubaboard.com/forums/basic-scuba-discussions/60261-deep-deep-diver.html

The thread got nasty towards the end and was closed, however it contains a lot of useful information on a sequence of courses than one can undertake to begin becoming familiar with technical diving.

Needless to say, no amount of c-cards will make you a good diver. Only experience, attititude and sheer ability/talent (mental and physical) will make you a good diver.

Doing bounce dives to 50m isn't the right or safe way to go about it.

 

[rookers]

Only experience, attititude and sheer ability/talent (mental and physical) will make you a good diver.

Training is a good place to start, however.

 

[Thalassamania]

So you've been to 40m and want to do 50, as a bounce. OK, it's really no big deal, there are a lot of naysayers here, but then few of them have actually done it, but their instructors (who haven't done it either) were told by their instructors (ditto) that it was a bad idea.

Actually DA's got it right, no big deal as long as nothing goes wrong. If something does, I hope hope you are prepared to do a 50 meter free ascent at a rate that is no faster than 20 meters per minute ... do think about it carefully first.

Anyway, descend to 150 meters in no more than two minutes. Stay there no longer than two minutes. Ascend to 25 meters at 20 meters per minute and stay there at 25 meters for one minute. Ascend to 3 meters at 10 meters per minute and stay there at 3 meters for 5 minutes. Surface at 10 meters per minute or less.

This is not a "technical dive" and technically it does not require any decompression, but the stops that I suggest, while a bit old school, should see you through.

Oh, yes, there is the question of a redundant breathing supply and a buddy of sufficient skill and experience who is willing to accompany you on a dive with such a seemingly small payback.