V-Planner

[Sloth]

Is 180 a new T1 limit?
Mine was ~160ft max but really the limit was more like ~25mins deco regardless of the depth you accumulated that at - long shallow vs shorter deeper.

Oh sorry, that's my personal comfort zone with my TDI trimix training using a 70' and 20' bottle, which is of course considered beyond GUE Tech 1 level. I'm not going to pass on a good dive in the 180 range just because I've now done Tech 1

T1 I think is the same limits as you mention. I didn't really pay much attention to the depth limits in class.

 

[Sloth]

Oh roger. Yeah and once you start extending deep stops into the 2 min range RB just keeps climbing too...

You are losing me. You are not extending deep stops to 2 mins. It's add one more minute for an emergency at depth then you are ascending faster through the "deep stops" (not really a good term for Tech 1 depths.) at 20ft per min instead of 10ft per min. I believe this change of ascent rates was in response into recent studies that showed that long deep stops aren't beneficial for short, shallow deco dives aka Tech 1 range.

At the tech 1 ranges I think its a wash. Old way for min gas at 150, 8 min ascent time to 70 including the minute for the gas switch. New way looks to be the same 8 mins but just shaped differently.

Just keep in mind that I have no idea what min gas calculation for Tech 2 range is now. I think I remember Gideon saying it was staying about the same as it was before. A dive buddy is in Tech 2 now so I'll see what he says.

 

[rjack321]

You are losing me. You are not extending deep stops to 2 mins. It's add one more minute for an emergency at depth then you are ascending faster through the "deep stops" (not really a good term for Tech 1 depths.) at 20ft per min instead of 10ft per min. I believe this change of ascent rates was in response into recent studies that showed that long deep stops aren't beneficial for short, shallow deco dives aka Tech 1 range.

At the tech 1 ranges I think its a wash. Old way for min gas at 150, 8 min ascent time to 70 including the minute for the gas switch. New way looks to be the same 8 mins but just shaped differently.

Just keep in mind that I have no idea what min gas calculation for Tech 2 range is now. I think I remember Gideon saying it was staying about the same as it was before. A dive buddy is in Tech 2 now so I'll see what he says.

For 150ft or even 160ft you get to 50% of depth basically when you get to the EAN50, so 1 min deep stops are fine.

For 180ft you need to put in more than 1 min deep stops starting at ~90ft (50% of depth)

Depending on the total exposure, the expanded deep stops from 50% of depth up to the EAN50 switch are typically 2 to 3 mins each.

For instance a 30min 200ft dive would have the following deep stop schedule:

200-30
2 mins up
150-1
140-1
130-1
120-1
110-1
100-2
90-3 (2 also probably ok, 30mins exposure is on the cusp)
80-3
70-switch

Warning this is not necessarily the strict GUE way. I can't figure out what the Tech2 rules are for deep stops nowadays. UTD's rules are much clearer and that's who I've been doing these dives with so that's what's shown above.

 

[Sloth]

I got you. My examples and changes were only for Tech 1 ranges using 1:1 RD compared to Tech 2s 2:1 RD where you start pushing time down into your deep stops. I'm not sure if GUE changed 2:1 RD to use 20 ft per minute until your first true deep stop or if it is still 10 ft per minute to your first deep stop.

 

[rjack321]

I got you. My examples and changes were only for Tech 1 ranges using 1:1 RD compared to Tech 2s 2:1 RD where you start pushing time down into your deep stops. I'm not sure if GUE changed 2:1 RD to use 20 ft per minute until your first true deep stop or if it is still 10 ft per minute to your first deep stop.

20ft/min (or worse 10ft/min) just to get UP to a deep stop is way way too slow. That is what most people do (we all tend to move too slow off the bottom - slow ascents have been drilled into us in excess), but you're basically ongassing throughout that time. You need to get UP off the bottom roughly 2ATAs before you're offgassing at all. Both deco planner and VPM illustrate this well. Then keep moving at a decent clip 30sec pause, 30sec slide for the "1 min stops" (or 10ft/min as its now described, same thing).

5mins to even get up from 200ft to a 150ft deep stop would require ALOT of rock bottom too.

 

[Sloth]

20ft/min (or worse 10ft/min) just to get UP to a deep stop is way way too slow. That is what most people do (we all tend to move too slow off the bottom - slow ascents have been drilled into us in excess), but you're basically ongassing throughout that time. You need to get UP off the bottom roughly 2ATAs before you're offgassing at all. Both deco planner and VPM illustrate this well. Then keep moving at a decent clip 30sec pause, 30sec slide for the "1 min stops" (or 10ft/min as its now described, same thing).

5mins to even get up from 200ft to a 150ft deep stop would require ALOT of rock bottom too.

I think you miss understood what I wrote. 200ft to 150ft would still be 30ft per min. I was referring to the rate of ascent from your 75% of depth to your first true deep stop or your gas switch depending on which comes first. Old GUE Tech 1 method was the 10ft per min rate or the 30 sec pause, 30 sec slide you mention. The new Tech 1 rate is 20 ft per min or 15 sec pause, 15 sec slide. What I don't know is if Tech 2 is now 20 ft per min until your first "true deep stop" (110 feet in your example) or if it is still 10 ft per min.

To me the 150 ft mark in your example isn't really a deep stop as much as a speed bump to slow down your rate of ascent. In my mind your 110 stop is your first true deep stop. To me anything with 1, 1, 1, (or less) for stops is a rate of ascent and not true stops. Probably not a good way for me to look at it as it does get confusing.

I think I am muddling the water

 

[rjack321]

I think you miss understood what I wrote. 200ft to 150ft would still be 30ft per min. I was referring to the rate of ascent from your 75% of depth to your first true deep stop or your gas switch depending on which comes first. Old GUE Tech 1 method was the 10ft per min rate or the 30 sec pause, 30 sec slide you mention. The new Tech 1 rate is 20 ft per min or 15 sec pause, 15 sec slide. What I don't know is if Tech 2 is now 20 ft per min until your first "true deep stop" (110 feet in your example) or if it is still 10 ft per min.

To me the 150 ft mark in your example isn't really a deep stop as much as a speed bump to slow down your rate of ascent. In my mind your 110 stop is your first true deep stop. To me anything with 1, 1, 1, (or less) for stops is a rate of ascent and not true stops. Probably not a good way for me to look at it as it does get confusing.

I think I am muddling the water

Ummm ok I guess, whatever works for you. I wouldn't be the slightest bit surprised for "deep stops" to change between GUE T1 and T2 depths. KMD just took GUE T2 so maybe he could comment.

We do "1 min" stops which are really about a 30 sec stop and 30sec slide. Sometimes they might be a 45sec stop and 15sec slide, sometimes the reverse, its not critical if you are using runtime. And before the uwtec tech2gs and X1 etc were invented everyone used the simple bottom timers so this was more obvious. Nowadays the advent of "seconds" has made things more complicated.

These "1 min stops" are the same thing across all depths they might be applied. Ie. a 1 min deep stop on a 150ft dive is the same as a 1min deep stop on a 210ft dive, they just happen at different depths.

 

[Sloth]

Talked to buddy who just finished Tech 2. moves from 75% of depth is still 10 ft per min until 50% of depth at which point it becomes 5 ft per min until gas switch. So unlike UTD method of moving half your intermediate stops down to your 50% of depth deep stops GUE is saying just do 2s from 50% of depth until gas switch.

So I guess your dive from a GUE Tech 2 standpoint would be:

200-30
2 mins up
150-1
140-1
130-1
120-1
110-1
100-2
90-2
80-2
70-switch

Pretty much the same I guess. Heh, guess the difference between UTD and GUE comes down to a minute or two

 

[rjack321]

Its a bit more complicated than that: Once you go over 60mins deco the 75% deep stops change to 2 mins each. And 50% deep stops change to 2mins at 30mins and 3mins at 45mins, 4mins at 60mins...
I'm not doing dive with more than about 60mins of deco gas time so I can't say how these might actually be applied. We round a bit in the 45 to 60min deco time window and exponential "shape" the stops from 50% of depth up the switch a little.

Still does not look anything like V-planner output :d

Talked to buddy who just finished Tech 2. moves from 75% of depth is still 10 ft per min until 50% of depth at which point it becomes 5 ft per min until gas switch. So unlike UTD method of moving half your intermediate stops down to your 50% of depth deep stops GUE is saying just do 2s from 50% of depth until gas switch.

So I guess your dive from a GUE Tech 2 standpoint would be:

200-30
2 mins up
150-1
140-1
130-1
120-1
110-1
100-2
90-2
80-2
70-switch

Pretty much the same I guess. Heh, guess the difference between UTD and GUE comes down to a minute or two

 

[Sloth]

Its a bit more complicated than that: Once you go over 60mins deco the 75% deep stops change to 2 mins each. And 50% deep stops change to 2mins at 30mins and 3mins at 45mins, 4mins at 60mins...
I'm not doing dive with more than about 60mins of deco gas time so I can't say how these might actually be applied. We round a bit in the 45 to 60min deco time window and exponential "shape" the stops from 50% of depth up the switch a little.

Still does not look anything like V-planner output :d

ahh cool, thanks for filling in the gaps. Figured i missed something when talking to my buddy.

i wonder if GUE and UTD will ever deviate so much that the systems are radically different and incompatible. Somehow i doubt it.