Cutting tables

[Zen Diver]

For example, if I'm divining with someone that is running a VR3, I know they'll have to do a 2 minute deep stop, so we leave tthe bottom 2 minutes early, go up and wait at the first deep stop for the run times to catch up, and then follow the table (this keeps the VR3's happy).

Hey Scott

If you are truly DIVINING with someone, you probably wouldn't need any kind of table, would you?

Sorry, couldn't resist

-Valerie

[Joshua Smith]

Lol- no, I'll pass on the Ratio for now.

Here's why I do what I do: If I'm doing a dive that I know will be below 200', but more than likely above 220', I cut a table for 220, and probably a BT of 20-25 minutes.....depends on what the dive is, and how much gas I wanna schlep, buddys, whatever. I will be very concientious about not overstaying my time, or descending below target depth. But, let's just say this is for a dive on a wreck that bottoms out at 240'- there are a couple that fit this profile I can think of. I'll probably cut another table for 240' and a slightly longer BT. Who knows what's gonna happen down there? We might see something really tempting a little deeper than our first plan. Someone could get tangled up in fishing line on the way back to the upline, causing the team to overstay planned bottom time. If I go even a little bit deeper or stay a little longer than my first plan, I will switch to my second. I've also cut up to 4 different plans for a range of bottom times and depths, but I don't like that approach as much. Some of my dive buddies like it, so I usually use it when I dive with them, but I prefer my way.

How would you do that dive?

[Joshua Smith]

For example, if I'm divining with someone that is running a VR3, I know they'll have to do a 2 minute deep stop, so we leave tthe bottom 2 minutes early, go up and wait at the first deep stop for the run times to catch up, and then follow the table (this keeps the VR3's happy).

Hey Scott

If you are truly DIVINING with someone, you probably wouldn't need any kind of table, would you?

Sorry, couldn't resist

-Valerie

Deco and "DIVINING" are very similar, actually!

[Burntchef]

wish i knew how to do a screen shot so i could post a schedule. i run one depth that has 10 feet added to it, then 4 different bottom time spreads spaced 2 minutes apart. and each b/t has a additional minute added to it as well.

great discussion though thanks for adding some good questions chris.

[vbcoachchris]

Wow this is a loaded question.

First I agree with you that decompression is not an exact science and that our body probably doesn’t know the difference between doing 2 min at 40 feet, 4 min at 30 feet or just doing 3 min at each stop. It is still 6 min total, so for me it's all about having a system that is easy to remember and very versatile.

If was doing the Al-IND-ESKA-SEA or the Governor (both about 240 ft to the mud, but more than likely a 220 foot dive) It would be planned accordingly.

First the Governor dive would require EVERY team to have their own boat; the AL may require this depending on conditions.
I would have an in water safety diver with each team. This diver will not have zero deco responsibility so they are free to move to the surface at anytime.

There is obviously a lot more to the logistics, but let’s just do the deco plan.

I will try to keep the time I arrive at my first gas switch the same, even if I go a deeper. I will not extend my time unless there is an issue that causes me too. If I see something cool that would make me want to stay longer, I will just come back and dive the site again a different day, since we try to have a coordinated meet time with our safety diver and I do not want them solo diving for any extended time.

Since 5 minutes at 220 feet is approximately equal to 10 min of additional deco there is no way I would plan a dive to that depth for that wide (20-25 min) of a time range. It would mean my safety diver would be hanging out alone for ten minutes.

My profile would look something like this:

Here is what v planner recommends/ what I would do.

Let me add that the reason I do what I do is it is easy to remember and easy to adjust if needed. I will ALWAYS put my exact profile(s) into v planner manually and see if it accepts it or see if it recommends I add additional stops. I always start my first deep stop 60 feet off the bottom on tech dives as it is the approximate location when VPM/RGBM puts them and since we travel at 30 ft /min it always takes me 2 min to get to my first deep stop. You will notice that I do a few more minutes deep and a few less shallow, but VPM/RGBM is FINE with this. I end up doing a few more min overall than VPM/RGBM recommends but again it is EASY to remember and EASY to adjust.

This is for 220 ft for 20 min

VPM on +2 / my profile (which is actually closer to +3)
160 no stop recommended/1 min
150 00:00:40/1
140 00:01:00/1
130 00:01:00/1
120 00:01:00/1
110 00:01:00/2
100 00:02:00/2
90 00:02:00/2
80 00:03:00/2
70 00:02:00/4
60 00:02:00/4
50 00:03:00/4
40 00:05:00/4
30 00:06:00/4
20 00:21:00/15
5 min up to the surface

With the above profile I will be at 70 feet (my first gas switch) at a 35 min run time

240 feet for 15 min
160 00:00:20/1
150 00:01:00/1
140 00:01:00/1
130 00:01:00/1
120 00:01:00/2
110 00:01:00/2
100 00:01:00/2
90 00:02:00/2
80 00:03:00/2
70 00:02:00/4
60 00:02:00/4
50 00:02:00/4
40 00:04:00/4
30 00:05:00/4
20 00:18:00/15
5 min up to the surface

Again with the above profile I will be at 70 feet (my first gas switch) at a 35 min run time.

No change to my safety team

If I do stay longer I have run several contingency profiles to account for the additional decompression.

There is a lot more to dive planning than this, such as gas reserves, but this gives you an idea of what my team does.

Scott

[vbcoachchris]

wish i knew how to do a screen shot so i could post a schedule. i run one depth that has 10 feet added to it, then 4 different bottom time spreads spaced 2 minutes apart. and each b/t has a additional minute added to it as well.

great discussion though thanks for adding some good questions chris.

This is my question: Why? I see what you do, but I would like to know the reason behind it. I am most defiantly not saying it is incorrect; I would just like to know the different thought processes.

The problems I had with this system are (and yes I did use it for a short time).


1. What if you did over stay your time by more than 10 min? Example you stay 6 because you saw something cool and then the "fit hits the shan" and it takes you SEVERAL minutes to sort out the issue. How would you deal with this since your schedule has only a 10 minute range? Assume reasonably shallow depth (150 ft or so) so gas is not an issue.

2. What if you over shot your depth by 15 feet (assuming your mix was flexible enough). Would you just bail on the dive?

3. Do you use run times or stop times? I used run times with this system and I found out if I was a little slow on the ascent I had to move over profiles. If you are 1 min late going from 60 ft to 50 ft do you really need move over to the next profile? This could amount to SEVERAL minutes of addition decompression.

4. What if you planned for 25-35 minutes of bottom time on your schedule, but you only stay 15 min. Do you do the deco for the 25 min schedule? If so how do you do the subtraction for your run times?

These are just a few issues I had with this system. Just curious how do you deal with them?

I was told to use this method because it is more conservative than straight VPM/RGBM, but I have found that if I need more conservatism, I just adjust my profile to match the higher level of conservatism that the program gives me, instead of just adding phantom minutes and depth.

In the end we should all do what make us feel warm and fuzzy inside.

Just curious about the different thought processes

I will check in later tonight ( I am off to DIVE)

Scott

[Joshua Smith]

Well, I can't speak for anyone else, but my thought process is this:

I plan for what I consider to be a reasonable range of contingencies. You can't plan for everything. Ratio is an interesting concept, but it scares me. I've heard a lot of stories about people getting bent doing it. I have no idea if any of them are true, but I'd love to see a real study on it some time. I see your point- ratio is great, because no matter what, you can always come up with a schedule.....but that's what my bink.....I mean my computer is for! Computer dies at max depth? I carry a range of schedules on the wetnotes in my pocket. Shark eats my wetnotes? I'll probably end up doing my own version of ratio, which I call "faking it". I've punched out a lot of plans on vplanner, and I have a pretty good idea what a dive profile should look like for a lot of different depths and times. I question everything, and I'm very new to this- I've only been planning and doing tech dives for a little more than a year and a half, so I consider myself a greenhorn. One thing about all the deco dives I've done so far that pleases me is that I've never been bent. I've had dives where I felt like I'd been hit by a truck afterwards, just real tired and sleepy, and I'm sure that it was sub-clinical DCS. I bet every tech diver has had dives like that. I started lingering a little longer at my 60 through 20 foot stops, and when I got the Meg, I started to play with elevating my p02 above 1.3 for intervals on deco, and I surface feeling just fine, these days. The point I'm making is that I started off diving like the people I was diving with did it......because I trust them, and they have been doing this successfully much longer than I have. (I'm consider myself lucky to have made some terrific friends with vast amounts of knowledge and experience that they share freely. I've learned as much about dive planning on dive boats and in the bar over cold beers as I did in the classes I took.) To me, real-world experience speaks much louder than a PHD in advanced lemon-wedge statistical mathematics analysis or whatever....So, to answer your "why" question, I guess it boils down to:

1- because people I trust have been doing it this way successfully for years

2- because it works for, and makes sense to, me.

But I'm always learning new stuff, too. Like Matt DenHaan says: "The more I learn, the less I know."

[boydski]

If you are truly DIVINING with someone, you probably wouldn't need any kind of table, would you?

Sorry, couldn't resist

-Valerie

OK Valarie, I just ordered myself a new keyboard. That's my Story and I'm sticking to it!

[boydski]

1. What if you did over stay your time by more than 10 min?

2. What if you over shot your depth by 15 feet. Would you just bail on the dive?

3. Do you use run times or stop times?

4. What if you planned for 25-35 minutes of bottom time on your schedule, but you only stay 15 min.


Scott

Hi Scott,

I hope you had a good dive today. I've been chained to my "broken" keyboard all day.

I can't answer for others but here are how I handle your questions above, which really boil down to, "what do you do when your dive plan goes down the drain"?

I carry a full set of VPM decompression tables with me (which gives me something to read on those Loonng deco stops). If you are over your contingencies, then pull out the table and figure out a new schedule. My preference is to follow a written schedule if I can. This helps when my mind wanders (sort of like my typing)...

Other options for getting safely out of the water when a dive is thumbed early or similar situation would be to fall back on ratio deco, or for short, shallower dives where I had to really get out of the water fast, I might even believe what my dive computer is telling me (but it lies a lot).

YMMV,

[Pez7378]

wish i knew how to do a screen shot so i could post a schedule. i run one depth that has 10 feet added to it, then 4 different bottom time spreads spaced 2 minutes apart. and each b/t has a additional minute added to it as well.

great discussion though thanks for adding some good questions chris.

This is my question: Why? I see what you do, but I would like to know the reason behind it. I am most defiantly not saying it is incorrect; I would just like to know the different thought processes.

The problems I had with this system are (and yes I did use it for a short time)....................


Scott

I hear you asking why he runs the schedule that he does. And, I hear you saying that before you identified some problems following that system, you also used to run that schedule. Why did you run that schedule? My guess is that the answer to the question "why" is that people dive the way that they are trained to dive. At least until they are exposed to another way of doing things, or find something else that works "better" for them.

[vbcoachchris]

Well, I can't speak for anyone else, but my thought process is this:

I plan for what I consider to be a reasonable range of contingencies. You can't plan for everything. Ratio is an interesting concept, but it scares me. I've heard a lot of stories about people getting bent doing it. I have no idea if any of them are true, but I'd love to see a real study on it some time. I see your point- ratio is great, because no matter what, you can always come up with a schedule.....but that's what my bink.....I mean my computer is for! Computer dies at max depth? I carry a range of schedules on the wetnotes in my pocket. Shark eats my wetnotes? I'll probably end up doing my own version of ratio, which I call "faking it". I've punched out a lot of plans on vplanner, and I have a pretty good idea what a dive profile should look like for a lot of different depths and times. I question everything, and I'm very new to this- I've only been planning and doing tech dives for a little more than a year and a half, so I consider myself a greenhorn. One thing about all the deco dives I've done so far that pleases me is that I've never been bent. I've had dives where I felt like I'd been hit by a truck afterwards, just real tired and sleepy, and I'm sure that it was sub-clinical DCS. I bet every tech diver has had dives like that. I started lingering a little longer at my 60 through 20 foot stops, and when I got the Meg, I started to play with elevating my p02 above 1.3 for intervals on deco, and I surface feeling just fine, these days. The point I'm making is that I started off diving like the people I was diving with did it......because I trust them, and they have been doing this successfully much longer than I have. (I'm consider myself lucky to have made some terrific friends with vast amounts of knowledge and experience that they share freely. I've learned as much about dive planning on dive boats and in the bar over cold beers as I did in the classes I took.) To me, real-world experience speaks much louder than a PHD in advanced lemon-wedge statistical mathematics analysis or whatever....So, to answer your "why" question, I guess it boils down to:

1- because people I trust have been doing it this way successfully for years

2- because it works for, and makes sense to, me.

But I'm always learning new stuff, too. Like Matt DenHaan says: "The more I learn, the less I know."

The stories are NOT true. Almost every person I have heard of that gets bent using ratio deco (and ther have only been a hand full) does so because of some creative depth averaging, not the profile itself. The profile would have worked fine had they really been at that depth for the time they thought.

Nowhere in my post did I say I ran ratio deco. I am a NAUI Tech Instructor and NAUI says NO to ratio deco. I always check every profile I run as well as every contingency profile to make sure VPM and RGBM are good with it. Don't get me in trouble.

Thanks for the insight behind your method.

Scott

[vbcoachchris]

Well, I can't speak for anyone else, but my thought process is this:

I plan for what I consider to be a reasonable range of contingencies. You can't plan for everything. Ratio is an interesting concept, but it scares me. I've heard a lot of stories about people getting bent doing it. I have no idea if any of them are true, but I'd love to see a real study on it some time. I see your point- ratio is great, because no matter what, you can always come up with a schedule.....but that's what my bink.....I mean my computer is for! Computer dies at max depth? I carry a range of schedules on the wetnotes in my pocket. Shark eats my wetnotes? I'll probably end up doing my own version of ratio, which I call "faking it". I've punched out a lot of plans on vplanner, and I have a pretty good idea what a dive profile should look like for a lot of different depths and times. I question everything, and I'm very new to this- I've only been planning and doing tech dives for a little more than a year and a half, so I consider myself a greenhorn. One thing about all the deco dives I've done so far that pleases me is that I've never been bent. I've had dives where I felt like I'd been hit by a truck afterwards, just real tired and sleepy, and I'm sure that it was sub-clinical DCS. I bet every tech diver has had dives like that. I started lingering a little longer at my 60 through 20 foot stops, and when I got the Meg, I started to play with elevating my p02 above 1.3 for intervals on deco, and I surface feeling just fine, these days. The point I'm making is that I started off diving like the people I was diving with did it......because I trust them, and they have been doing this successfully much longer than I have. (I'm consider myself lucky to have made some terrific friends with vast amounts of knowledge and experience that they share freely. I've learned as much about dive planning on dive boats and in the bar over cold beers as I did in the classes I took.) To me, real-world experience speaks much louder than a PHD in advanced lemon-wedge statistical mathematics analysis or whatever....So, to answer your "why" question, I guess it boils down to:

1- because people I trust have been doing it this way successfully for years

2- because it works for, and makes sense to, me.

But I'm always learning new stuff, too. Like Matt DenHaan says: "The more I learn, the less I know."

The stories are NOT true. Almost every person I have heard of that gets bent using ratio deco (and ther have only been a hand full) does so because of some creative depth averaging, not the profile itself. The profile would have worked fine had they really been at that depth for the time they thought.

Nowhere in my post did I say I ran ratio deco. I am a NAUI Tech Instructor and NAUI says NO to ratio deco. I always check every profile I run as well as every contingency profile to make sure VPM and RGBM are good with it. Don't get me in trouble.

Thanks for the insight behind your method.

Scott

[vbcoachchris]

wish i knew how to do a screen shot so i could post a schedule. i run one depth that has 10 feet added to it, then 4 different bottom time spreads spaced 2 minutes apart. and each b/t has a additional minute added to it as well.

great discussion though thanks for adding some good questions chris.

This is my question: Why? I see what you do, but I would like to know the reason behind it. I am most defiantly not saying it is incorrect; I would just like to know the different thought processes.

The problems I had with this system are (and yes I did use it for a short time)....................


Scott

I hear you asking why he runs the schedule that he does. And, I hear you saying that before you identified some problems following that system, you also used to run that schedule. Why did you run that schedule? My guess is that the answer to the question "why" is that people dive the way that they are trained to dive. At least until they are exposed to another way of doing things, or find something else that works "better" for them.

It only took few dives for me to figure out that method would not work for my style of diving. I was told only that it was more conservative. That didn't sit well, so I start to look deeper (I always want to know “why?”). I have found that I like the conservatism that the program gives me and not one that I make up, but I am always looking for more source of information. I was just hoping to find out something new.

Scott

[vbcoachchris]

1. What if you did over stay your time by more than 10 min?

2. What if you over shot your depth by 15 feet. Would you just bail on the dive?

3. Do you use run times or stop times?

4. What if you planned for 25-35 minutes of bottom time on your schedule, but you only stay 15 min.


Scott

Hi Scott,

I hope you had a good dive today. I've been chained to my "broken" keyboard all day.

I can't answer for others but here are how I handle your questions above, which really boil down to, "what do you do when your dive plan goes down the drain"?

I carry a full set of VPM decompression tables with me (which gives me something to read on those Loonng deco stops). If you are over your contingencies, then pull out the table and figure out a new schedule. My preference is to follow a written schedule if I can. This helps when my mind wanders (sort of like my typing)...

Other options for getting safely out of the water when a dive is thumbed early or similar situation would be to fall back on ratio deco, or for short, shallower dives where I had to really get out of the water fast, I might even believe what my dive computer is telling me (but it lies a lot).

YMMV,

Now this is the answer I am looking for. I can follow "why" you do what you do.

Vis was great at cove 2

Thanks

Scott

[Joshua Smith]

1. What if you did over stay your time by more than 10 min?

2. What if you over shot your depth by 15 feet. Would you just bail on the dive?

3. Do you use run times or stop times?

4. What if you planned for 25-35 minutes of bottom time on your schedule, but you only stay 15 min.


Scott

Hi Scott,

I hope you had a good dive today. I've been chained to my "broken" keyboard all day.

I can't answer for others but here are how I handle your questions above, which really boil down to, "what do you do when your dive plan goes down the drain"?

I carry a full set of VPM decompression tables with me (which gives me something to read on those Loonng deco stops). If you are over your contingencies, then pull out the table and figure out a new schedule. My preference is to follow a written schedule if I can. This helps when my mind wanders (sort of like my typing)...

Other options for getting safely out of the water when a dive is thumbed early or similar situation would be to fall back on ratio deco, or for short, shallower dives where I had to really get out of the water fast, I might even believe what my dive computer is telling me (but it lies a lot).

YMMV,

Now this is the answer I am looking for. I can follow "why" you do what you do.

Vis was great at cove 2

Thanks

Scott

And, it's pretty close to my own answer- cheers, Boydski!

Scott- sorry, had no intention of getting you into any trouble with anyone- just looked like you were a r/d advocate. As I said above- I know absolutely nothing first hand, but would love to see a real study done on the topic. For now, I am following in the footseps of more experienced divers who have been doing the dives I want to do for years and years. And none of them uses ratio- if ratio was the tool they used, I'd probably be using ratio- but none of them are. I want to know someone who has actually used a technique personally, and talk to them and get to know and trust them, before I try something new. Then, I'll see how it works for me, and perhaps consider making adjustments to it. Sound about right?

[Burntchef]

ok let me start off by stating i am a fng to the tech diving world, and as a good fng i follow what my instructor has trained me to do but allways learning from those who are doing the dives cleanly for years. but i do ask why and just like you scott i am sure over time i will develop a method that works for me and my buddy. and speaking of buddies we havent mentioned that yet, what works for me may not for my buddy and that is something that is worked out ahead of time.

yes i wondered why i would alter a program that wasnt really meant to be altered but in the simplest terms it made sense to me and still does. i havent really played with the conservatism factors in v-planner yet but have plans to do so. probably cut one table my way then change setting and do a plan that way and dive both and see what i like.

as far as going over depth if i have allready lied to v-planner and added 10 feet i dont go 20 feet over period. that is another reason i added 10 feet, if there is something cool a little deeper then i am still good. if we get to depth and vis sucks and we decide to bag it and i dont have a plan for 5 minutes of b/t i will come up with a plan on the fly and keep it close to my first schedule. if everyone is fine im not concerned with getting out of the water fast, i didnt spend stupid amounts of cash to be dry

if we over stay our last schedule by a few minutes due to a issue again we will come up with something on the fly as well and use my lost deco gas schedule as ending point since that is worst case scenario. my l/g schedule is allways for longest b/t .

and as to question 3 if we go over one minute going from 60 to 50 no we dont move over to the next schedule, if deco was that exact we would all be using exact computers and it would be called science not theory.

if this makes sense cool, if not lets continue on.

[vbcoachchris]

ok let me start off by stating i am a fng to the tech diving world, and as a good fng i follow what my instructor has trained me to do but allways learning from those who are doing the dives cleanly for years. but i do ask why and just like you scott i am sure over time i will develop a method that works for me and my buddy. and speaking of buddies we havent mentioned that yet, what works for me may not for my buddy and that is something that is worked out ahead of time.

yes i wondered why i would alter a program that wasnt really meant to be altered but in the simplest terms it made sense to me and still does. i havent really played with the conservatism factors in v-planner yet but have plans to do so. probably cut one table my way then change setting and do a plan that way and dive both and see what i like.

as far as going over depth if i have allready lied to v-planner and added 10 feet i dont go 20 feet over period. that is another reason i added 10 feet, if there is something cool a little deeper then i am still good. if we get to depth and vis sucks and we decide to bag it and i dont have a plan for 5 minutes of b/t i will come up with a plan on the fly and keep it close to my first schedule. if everyone is fine im not concerned with getting out of the water fast, i didnt spend stupid amounts of cash to be dry

if we over stay our last schedule by a few minutes due to a issue again we will come up with something on the fly as well and use my lost deco gas schedule as ending point since that is worst case scenario. my l/g schedule is allways for longest b/t .

and as to question 3 if we go over one minute going from 60 to 50 no we dont move over to the next schedule, if deco was that exact we would all be using exact computers and it would be called science not theory.

if this makes sense cool, if not lets continue on.

Nope that’s good information. I most certainly wasn’t criticizing you I was just curious.

Thanks

Scott

[narcosis Junky]

Just my two cents.
I use V-planner. and I use conservation at +2.

If I plan my dive at 200 feet for 20 min. Instead of changing any of the times, I write the 200 feet for 20 min on my slate, and as a back up , I write both 210 feet for 20 min. and 200 feet for 25 minutes. So if I deviate from the plan for any reason, I look at the back up plan. I try to write down on my slate 2 to 3 back ups. Ever tried to change the numbers on your plan when you are narked up. Not a good mix. So the best thing to have is a back up plan. There is a lot of room on a slate. It's ok to write 3 plans on there. That's my two cents. Keep it simple! Oh if you stick to the original plan, Things go a lot smoother. Keep it simple.

[dsteding]

Note that this is all for certain depths, times, and gases, I haven't run all the combinations:


For those of you using V-Planner (or VPM-B based deco software):

For a ~150 ish dive on 21/35 and 50% you'll see the following:

If you set "levels" of 110-80 for one minute and then a switch to 50% at 70 feet with a 3,3,1,1,2,6 profile (from 70-20) what you'll see is that VPM gives you 4 minutes of deco at 10 feet (3:40 actually).

If you do this for 140 for 25, or 130 for 25 or other variants (using the same "levels" coming up, deep stops at 110 or 100 and extending to 80 feet with a 3,3,1,1,2,6 from 70-20) you'll see remarkable similarities in terms of the time at 10 feet (anywhere from 0-4 minutes).

What this says to me is that you can treat a deco dive within the 150 range as a "multi-level" dive in one sense of the approach. Plug it into VPM and VPM won't penalize you for the deep stops (makes sense because ~100-110 is where you start to offgas on these profiles), run your stops from 70-20 as you are, and then validate you ten foot stop with VPM. Make any sense? You really need to run the numbers to see how this shakes out.

Therefore, in that range of 150 for 20, 140 for 25, or even 160 for 15, the deep stops from 110-80 feet for a minute and then 3,3,1,1,2,6 works for VPM. Not the "default" profile that VPM would spit out but one that will clear you with 4 minutes at 10 feet.

That 3,3,1,1,2,6 profile can then become the "default" one in your head.

Long way of explaining that you can really simplify all of the above approaches in the ~150 range on these gases . . . VPM validates that you can reduce those dives to a ~20 minute bottom time and run a standard type profile. If you overstay your time, adding time to that profile will get you out of the water, and if you understay your time or have a shallower depth, you are being a bit more conservative.

[LCF]

And that type of analysis, Doug, is where Ratio Deco came from!

[Burntchef]

so i have one real honest non war starting question, this is not to discredit ratio deco or any poo flinging!! if it goes south i will have the mods wipe it out. and this is more for me and knowing my mental capacity of memory storage.

if on a tech dive and you are using ratio do you still have tables to confirm what your mind has told you? if not my biggest worry would be if the fit hits shan do you still have the clarity to sort out a schedule? this is where i would default to my computer. and no you cant use your buddy since i am assuming it is he who had the issue you had to sort out.

[dsteding]

if not my biggest worry would be if the fit hits shan do you still have the clarity to sort out a schedule? this is where i would default to my computer. and no you cant use your buddy since i am assuming it is he who had the issue you had to sort out.

Honestly, if my buddy had the issue, yes, I know I can maintain a clear enough head to refigure deco on the fly. If I have a problem, I am quite confident in all the people that I tech dive with in terms of their ability to do the same. I do however, plan with v-planner to verify what I'm planning.

I've buddy breathed off the bottom while managing a maskless diver, and have had the crap hit the fan in class more than I know will ever happen in reality. Multiple failures that just kept coming and coming and coming and coming all the way to the surface-we needed to keep the schedule, keep track of each other, and think through the problems as the arose. That was the purpose of class-Andrew's whole goal was to ensure you were able to maintain a cool head and a 'zen-like state" when the poo goes flying. He's quite capable of teaching that.

Keeping track of depth and time is all there is to it. If you aren't doing that on tech dives, then there are bigger issues, imho (as a tech diving newbie).

[Joshua Smith]

Best reasoning I've heard for R/D yet. I want to run some R/D profiles vs. V-planner and see what they look like. What ratio do you use? I think I've heard 1:2 for <200, and 1:3 for greater? Or am I totally making that up?

if not my biggest worry would be if the fit hits shan do you still have the clarity to sort out a schedule? this is where i would default to my computer. and no you cant use your buddy since i am assuming it is he who had the issue you had to sort out.

Honestly, if my buddy had the issue, yes, I know I can maintain a clear enough head to refigure deco on the fly. If I have a problem, I am quite confident in all the people that I tech dive with in terms of their ability to do the same. I do however, plan with v-planner to verify what I'm planning.

I've buddy breathed off the bottom while managing a maskless diver, and have had the crap hit the fan in class more than I know will ever happen in reality. Multiple failures that just kept coming and coming and coming and coming all the way to the surface-we needed to keep the schedule, keep track of each other, and think through the problems as the arose. That was the purpose of class-Andrew's whole goal was to ensure you were able to maintain a cool head and a 'zen-like state" when the poo goes flying. He's quite capable of teaching that.

Keeping track of depth and time is all there is to it. If you aren't doing that on tech dives, then there are bigger issues, imho (as a tech diving newbie).

[vbcoachchris]

Old school

1:1 at 150
1:2 at 220
1:3 at 270

New School

1:1 at 150
1:2 at 200
1:3 at 250


The above are just basic starting set points.

until you find one that works for you

Scott

[BDub]

I've stayed away from this conversation, deliberately.

However, I would like to add, without derailing the conversation, but it's something I think needs to be said, this isn't something that should be learned on the internet (this is directed more towards the lurkers) as R/D has a set of parameters, one of which is gas selection (backgas AND deco). I'll leave it at that.

Stepping off the soapbox now.....