Info Helium is expensive and deep air is not my thing. -Let's talk about "Big" dives.

[grantctobin]

TDI is phasing this out before long ? "Extended Range (air)?" Or will it continue?

TDI has attempted to do so a few times, and then a small subset of instructors claim "no, it's still safe and relevant and we don't have options," and then it stays.

 

[lermontov]

There’s nothing smart about doing 60 -70m dives On air that sort of chestthumping BS is from a previous generation that has no place in today’s technical diving
Sadly those who do those dives on air seem to want to tell everybody about how they did the dive on air more so than what they actually saw- Probably because They can’t remember anything

 

[Learner Diver]

Plan a dive to 40 meters on Air with 40 minutes bottom time.
Total Dive time is 100 minutes with ~35 minutes spent with deco 50% between 6-3meters.

Would doing two of those dives you have described above in a single day be considered a big dive? Could I ask how long of a surface interval would be appropriate for you?

 

[johndiver999]

There’s nothing smart about doing 60 -70m dives On air that sort of chestthumping BS is from a previous generation that has no place in today’s technical diving
Sadly those who do those dives on air seem to want to tell everybody about how they did the dive on air more so than what they actually saw- Probably because They can’t remember anything

Yeah, but YOU need to get with the times. A Gopro is so cheap that you can now film the entire (deep air) dive; so even if you don't remember it, you have a nice recording of it.

 

[SelfDiver]

Would doing two of those dives you have described above in a single day be considered a big dive? Could I ask how long of a surface interval would be appropriate for you?

You can plan two dives to 40meters for 40 minutes in a day with a 3 hour surface interval.
The OTU should be below 300 and %CNS should be below 70% on air with 50% and 80% deco gasses.
Your second dive will have a much longer decompression obligation and the gas plan should account for that.
But, I am an idiot on the internet and you should learn to plan consecutive deco dives from a proper instructor.

 

[SelfDiver]

Honestly I mostly see a giant mess of cylinders here and zero thoughts about any kind of video or mentor feedback. So knock yourself out, but you are mostly giving yourself a false sense of confidence that your bottle rotations actually are clean and you could in theory deal with an emergency midwater etc.

I mean right off the bat I can say you aren't going to be doing a 100m OC dive on 4x 80s anywhere North of FL and that would be iffy too.

I agree with everything you are saying except "A giant mess of cylinders" 4 tanks are not a giant mess.

I apologize if my original post did not state some assumptions about the level of divemanship (is that a word?)
The assumption is that you are already qualified and trained to dive Trimix to 80 meters and beyond. This implies that you have had "video or mentor feedback", your "bottle rotations actually are clean" and that you can "deal with an emergency midwater etc."

I think that 80-100 meters is still OK for OC but too expensive. (Every bubble from the regulator is like $3)
The jump to CCR is needed for anyone doing more than 10 helium dives a year.

 

[divezonescuba]

Yeah, but YOU need to get with the times. A Gopro is so cheap that you can now film the entire (deep air) dive; so even if you don't remember it, you have a nice recording of it.

That is an interesting idea.

My symptoms are more anxiety or paranoia like, not classical narcosis symptoms. Usually in the form of wanting to get the dive over with, which I might not otherwise want to do, if I was using He.

I will have to video myself, not the dive, to actually see if I can actually notice any strange behavior. Maybe even do a few math problems, etc.

 

[rjack321]

I agree with everything you are saying except "A giant mess of cylinders" 4 tanks are not a giant mess.

I apologize if my original post did not state some assumptions about the level of divemanship (is that a word?)
The assumption is that you are already qualified and trained to dive Trimix to 80 meters and beyond. This implies that you have had "video or mentor feedback", your "bottle rotations actually are clean" and that you can "deal with an emergency midwater etc."

I think that 80-100 meters is still OK for OC but too expensive. (Every bubble from the regulator is like $3)
The jump to CCR is needed for anyone doing more than 10 helium dives a year.

Shrugs fine then you were awesome and A+ coming out of class (unlikely but ok) how do you know you're actually maintaining proficiency not getting sloppy?

Maybe its time to skip the 60m+ dives.

 

[Learner Diver]

You can plan two dives to 40meters for 40 minutes in a day with a 3 hour surface interval.
The OTU should be below 300 and %CNS should be below 70% on air with 50% and 80% deco gasses.

How can I plan these two dives theoretically speaking?

But, I am an idiot on the internet and you should learn to plan consecutive deco dives from a proper instructor.

This info you have graciously provided is your personal experience? Are there technical instructors who have dived twice a day to these depths?

 

[lermontov]

Yeah, but YOU need to get with the times. A Gopro is so cheap that you can now film the entire (deep air) dive; so even if you don't remember it, you have a nice recording of it.

why bother i can live vicariously through scuba board