Planning multi-level deco dive?

[waterpirate]

What would you do if you have an regulator failure at 160 feet? Will you use your backgas at po2 of 1.9?


Ontopic:
I wouldn't do the dive at all. It Would be a deep dive with trimix or a shallow dive with ean32. (Or two dives) But I wouldn't stay most of the dive at less than 100 feet when using trimix. That is a waste of helium for me.

OMG you are going to die!
Every time we get in the water we are taking a risk. Every divers risk assessment is different for every dive. You missed the point that my advice may kill you, it will not kill me. There is safety in numbers and safety in the shallows. Maintain your gear and it will maintain you. If you are not comfortable, do not do the dive.
YMMV
Eric

 

[rjack321]

I would not just instabuddy up for a deco dive. I might if I knew and conversed with the person online beforehand and our mutual Q&A demonstrated that they had a clue. But still wouldn't do more than about 20mins of deco and I'd have a ton of extra helium in my mix to help compensate for the unexpected. I for sure would match gases and have a common understanding of their GFs and backup plans.

 

[tursiops]

Stuart, think about taking a Trimix class from some Pensacola-local TDI instructor. Do the dive(s) on the O. You've got a buddy, less narced, and you are on your way.

 

[Doby45]

Stuart, think about taking a Trimix class from some Pensacola-local TDI instructor. Do the dive(s) on the O. You've got a buddy, less narced, and you are on your way.

Your wisdom oozes forth and is spot on.

 

[stuartv]

Stuart, think about taking a Trimix class from some Pensacola-local TDI instructor. Do the dive(s) on the O. You've got a buddy, less narced, and you are on your way.

I will only have 1 day to pop over to P'cola while I'm down visiting family in Tallahassee for Thanksgiving, which is not enough time for a Trimix class.

Plus, it's kinda ironic. Before I started AN/DP, I felt like I was ready and could handle it and so many people on here basically told me no, don't do it. They said I didn't have sufficient experience, etc.. Now, I feel like I am not ready to move on to full normoxic Trimix. I want more experience doing deco dives and managing one deco cylinder before I step up to managing multiple deco cylinders. So, I don't feel ready for Trimix yet and now you are not the first person in this thread to suggest I go ahead and take Trimix (or otherwise learn how to manage multiple deco cylinders) in prep for diving the O. Kinda ironic. I do appreciate the advice. I am tentatively planning to do Trimix next Fall. But, I am not stepping up to that just yet. As quoted by the bard, Dirty Harry, a man's got to know his limitations.

 

[boulderjohn]

Different people progress at different rates by following different paths. Less than two years ago I met a brand new OW diver to begin his AOW class only a few days after he completed the OW. It was the first time he had seen a dry suit and a BP/W setup, and he was intrigued. I don't remember how many months later he joined me for tech training. At the same time he was doing that, he was working on his DM rating. He was soon an instructor, and soon after that he was full trimix certified as well. Today he is working as a full time dive professional, and he is in training for commercial diving.

How did he do that? He pretty much made it his job to get where he wanted to be. I would guess that in those two years he has completed several times as many dives as some of the people telling you to take it slow, and these were not just repetitions of introductory dives. If you dedicate yourself that way, you can progress a whole lot faster than someone who goes out and repeats the same basic OW dives every other weekend. Such a person does indeed need a long time to get to more advanced levels, if they ever get there at all. With proper training and enough practice, you can progress very quickly.

 

[Tassi Devil Diver]

have not gone through and read this whole thread.

A lot of my deco diving is multi level exploring deep reef, I usually have no idea what the profile will be, some times the max depth is uncertain.

I basically plan for a maximum time to surface, might be 30 minutes, 40 minutes or an hour, and plan bailout or deco gas accordingly, if I go deeper obviously bottom time is shorter. I use two deco computers, one as a back up, don't carry a written plan. I will play around with depths and profiles beforehand on multideco looking at a couple of scenarios.

But to make the most of this sort of diving you really need two computer.

 

[RainPilot]

The bonus of two computers of course is to run an "emergency " GF on one, say 80/90

That will give you the "least gas used" ascent for those pesky gas loss moments

 

[barth]

OMG you are going to die!
Every time we get in the water we are taking a risk. Every divers risk assessment is different for every dive. You missed the point that my advice may kill you, it will not kill me. There is safety in numbers and safety in the shallows. Maintain your gear and it will maintain you. If you are not comfortable, do not do the dive.
YMMV
Eric

For me it doesn't make sense to make an easy dive so complicated. It could just be an dive with doubles and a stage filled with decogas.

Your plan is adding a stage with a bottomgas.

I do understand that every time I get into the water I'm taking a risk. But why taking more risk and make it so complicated for 3 minutes less deco or something like that?

Maybe I'm wrong or missing something, but I don't understand why somebody would do a dive like that.

Maintaining gear is always good but has nothing to do with the diving plan I think.

 

[Diver2018]

I do realize this is an old thread. tbh, I found the conversation very enlightening.
My question, did you ever do the dive? And if so, what did your plan end up being?