Differences Between UTD and GUE

[boomx5]

Not that well, really. He did a full 7 hours on Monday and went back for 2 more hours yesterday. He still has some residual numbness in his right hand. The doctor is pretty sure he took a hit to the spine.

There was an additional complicating factor in that we had to cross a pass with a couple thousand feet of elevation gain about 3-4 hours after the dive. In preparation for that, we finished off the AL 40s of O2 and the AL80 safety bottle (only half full) while we were driving. We thought we were OK, but his came on while he was trying to sleep that night.

Wow! That's really terrible! Hopefully he get's well soon! For us, we have to drive up over 7,000'...back down to Truckee and then back up over the Donner Summit again which is over 7,000'...then back home to the Sacramento Valley. I can stay roughly at lake level till the summit...but it's a longer drive if I'm diving the Nevada side of Tahoe. I personally never have liked using strickly O2 for deco...I've just never got out feeling that great on some of the longer bottom times (60+ minutes) in 100' range. Slowing down the ascent through the 40' & 30' segments have helped that a bit though. We're looking at doing some doppler next year leading up to and during our project. Hopefully we can get some good data.

 

[Blackwood]

You said VP gives more O2 time than RD for this dive. What did you calculate the O2 time at on RD? I get 15 minutes from VP (I didn't bother to add the elevation info). I don't get less time on RD, but curious how you're calculating the requirement.

Are you figuring it both ways? Time over MDL would result in 5 minutes less deco than the 150 setpoint.

Personally, and this is neither here nor there, but that dive profile is a bit aggressive for my taste. Maybe it's my inexperience talking, but when the O2 time starts clicking up above 20 (of 15 on 5 off as the case may be), I'm going to start eyeballing a 70-bottle.

 

[Rainer]

Are you figuring it both ways? Time over MDL would result in 5 minutes less deco than the 150 setpoint.

Personally, and this is neither here nor there, but that dive profile is a bit aggressive for my taste. Maybe it's my inexperience talking, but when the O2 time starts clicking up above 20 (of 15 on 5 off as the case may be), I'm going to start eyeballing a 70-bottle.

I did it two ways and got the same answer. 150 setpoint is 43-10 (33 min of deco). For the table way I only take a 10% depth credit for 25/25, so get 120', so again, 33 min over NDL (edit: that is assuming a pretty conservative NDL limit, so yeah, the table method *could* lead to even less required deco).

I'd also do the O2 segment at 20' then five up.

This does seem like a pretty aggressive dive, though. What's the UTD Tech 1 limit for max deco?

John, how many other dives like this had you (and more importantly, your buddy) done without problems? Any chance you got the average depth wrong?

 

[boulderjohn]

I did it two ways and got the same answer. 150 setpoint is 43-10 (33 min of deco). For the table way I only take a 10% depth credit for 25/25, so get 120', so again, 33 min over NDL.

I'd also do the O2 segment at 20' then five up.

This does seem like a pretty aggressive dive, though. What's the UTD Tech 1 limit for max deco?

John, how many other dives like this had you (and more importantly, your buddy) done without problems? Any chance you got the average depth wrong?

I've got to run, so this is the last message for a while. I was very sure of the average--at least that is what my Uwatec bottom timer gave me.

 

[Blackwood]

For the table way I only take a 10% depth credit for 25/25, so get 120', so again, 33 min over NDL.

Oh okay, I was giving it 20%.

I'd also do the O2 segment at 20' then five up.

Yah, without giving it much thought, just looking at his bottom segment I'd probably have called it as (starting at 90') 1-1-2-2-3-3-4-15-3(ascending and coming off the bottle).

What's the UTD Tech 1 limit for max deco?

It's a bit esoteric, but the meat of it is 15 minutes of O2 time.

 

[Rainer]

Oh okay, I was giving it 20%.

And as I note in my edit, I was being pretty conservative with the NDL (10 at 120), so yeah, you could come up with even less required deco.

Yah, without giving it much thought, just looking at his bottom segment I'd probably have called it as (starting at 90') 1-1-2-2-3-3-4-15-3(ascending and coming off the bottle).

I'd shape it slightly differently in the pre-20' range (more exponential) but the time is about right (I'd do slightly less). I'd have done like John and added in the extra 3 minutes over planned time as well.

It's a bit esoteric, but the meat of it is 15 minutes of O2 time.

That's what I'd figured. This dive is definitely right up against those limits. I'd have brought the 70 bottle, but I'm still really surprised to hear the buddy got bent.

 

[radagalf]

Thanks for the links Blackwood, I'll check those out tonight.

For those interested I found these websites to provide some interesting material. It does look like the whole GI / AG thing started more on a he said / she said thing... someone please update me if I'm missing something.

Ratio Deco Discredited and Disowned? - Page 2 - FiNS Forum

http://forum.5thd-x.com/viewtopic.php?p=4463&highlight=#4463

 

[M_Bipartitus]

wow, interesting links. Most of it only reinforces the impression I've gotten about GUE being ego driven at the top. I don't understand how anyone from GUE can legitimately accuse an instructor of being motivated by money when JJ is the CEO of a manufacturing company.

 

[Blackwood]

wow, interesting links. Most of it only reinforces the impression I've gotten about GUE being ego driven at the top. I don't understand how anyone from GUE can legitimately accuse an instructor of being motivated by money when JJ is the CEO of a manufacturing company.

Like radagalf mentioned, it's a lot of "he-said-she-said."

 

[boomx5]

Like radagalf mentioned, it's a lot of "he-said-she-said."

I remember when all this crap was going down. I actually called AG when he was in Austrailia and told him about the venom George was spewing. There was an incident with (at the time) a local guy that had a runaway inflator issue and George was blamming in on the Argon mounting system that AG was promoting. The fact is, Halcyon made the same system, but Andrew was getting blammed for promoting his version. It's funny to read this stuff now and see all the glaring holes in Georges attacks on Andrew. There are a lot of other things that went on with this...I'm just glad we've all moved on.