Stop depths

[JohnD]

Originally Posted by nickb

I reckon it's 1m/min from around 10m up

give the man a coconut! 20m/min descent, 10m/min ascent then 6m-0m at 1m/min. ascent rate set slow for using trimix. descent rate set for my usual buddy using RB

[rossh]

Originally Posted by NotDeadYet

Deco software is different. It has to look ahead through the entire profile and that is where VPM falls down. On multilevel profiles where you are hitting it with relatively large depth and time changes and expecting it to calc the
ascent ceiling then it may just sit and sulk. It can have real trouble tracking the model this way. In Buhlmann it is simple as you only need to track gas loadings but VPM has a host of bubble related calcs to do when a profile is entered and the bigger the change then the more chance of it crashing.

Stuart

The V-Planner implementation of VPM has addressed and rectified all of these problems. Multilevel plans may even produce intermediate deco stops between the selected levels.

Regards

[NotDeadYet]

Hi Ross,

well done! Does that mean I can give it a start and end depth and tell it how long I will take to swim between them rather than just having it assume a constant ascent/descent rate for any depth change?

Cheers,

Stuart

[gobfish1]

Originally Posted by JohnD

Gas availability is a problem for the dive this weekend, so I have to use what I have. I like to keep to an END of 40metres or PPN2 of 3.95, but this is what I have in my twin 12s (using the "rule of 1/3s). I personally would not use a 3litre for anything but a pony, not enough gas available using "rule of 1/2s" for deco for your buddy if he loses his. I will be using 7.5litre sideslungs, more gas available.
GARF, I cant work out the simulation mode on the dive manager software using multiple mixes, but I can do it using the Vytec itself as it changes to the next gas (at its max PO2 set) as you ascend.

The Gas Rules all look ok to me, Not that I stick to them , but I do like to have
plan A B and C

Plan A
Waypoint at 43m for 25:00 (26) on Air, PPO2 1.107, END 43
Deep Stop at 27m for 2:00 (29) on Air, PPO2 0.773, END 27
Deep Stop at 21m for 2:00 (32) on Air, PPO2 0.648, END 21
Deep Stop at 15m for 2:00 (35) on Air, PPO2 0.523, END 15
Norm Stop at 9m for 1:00 (36) on Air, PPO2 0.398, END 9
Norm Stop at 6m for 5:00 (41) on 100% Oxygen, PPO2 1.596, END 0
Norm Stop at 3m for 10:00 (50) on 100% Oxygen, PPO2 1.298, END 0

TOTAL DECO TIME: 22 minutes.
DIVE RUN TIME: 50 minutes.
CNS Total: 25.6%

2655.0 Ltr. of 21.0% consumed. Twin 12L
241.7 Ltr. of 100.0% consumed. 3L cylinder
.

Bailout plan B
Waypoint at 43m for 25:00 (26) on Air, PPO2 1.107, END 43
Deep Stop at 27m for 2:00 (29) on Air, PPO2 0.773, END 27
Deep Stop at 21m for 2:00 (32) on Air, PPO2 0.648, END 21
Deep Stop at 15m for 2:00 (35) on Air, PPO2 0.523, END 15
Norm Stop at 9m for 1:00 (36) on Air, PPO2 0.398, END 9
Norm Stop at 6m for 10:00 (46) on Air, PPO2 0.335, END 6
Norm Stop at 3m for 26:00 (72) on Air, PPO2 0.273, END 3

Or buddy s o2 at 50mins Plan C

TOTAL DECO TIME: 43 minutes.
DIVE RUN TIME: 71 minutes.
CNS Total: 12.0%

3247.8 Ltr. of 21.0% consumed. Twin 12L


A Pony may only be a pony to you , But to me its 600L or 695L of gas and in the case above it’s more than twice the quantity of gas that I need ,




Plan A
Waypoint at 43m for 25:00 (26) on Nitrox 26.0, PPO2 1.370, END 40
Deep Stop at 27m for 2:00 (29) on Nitrox 26.0, PPO2 0.957, END 25
Deep Stop at 21m for 2:00 (32) on Nitrox 26.0, PPO2 0.802, END 19
Deep Stop at 15m for 2:00 (35) on Nitrox 26.0, PPO2 0.647, END 13
Norm Stop at 6m for 3:00 (38) on 100% Oxygen, PPO2 1.596, END 0
Norm Stop at 3m for 9:00 (47) on 100% Oxygen, PPO2 1.298, END 0

TOTAL DECO TIME: 18 minutes.
DIVE RUN TIME: 47 minutes.
CNS Total: 27.6%

2644.7 Ltr. of 26.0% consumed. Twin 12L
190.3 Ltr. of 100.0% consumed. 3L cylinder

Bail out plan B

Or buddy s o2 at 47mins plan C

Waypoint at 43m for 25:00 (26) on Nitrox 26.0, PPO2 1.370, END 40
Deep Stop at 27m for 2:00 (29) on Nitrox 26.0, PPO2 0.957, END 25
Deep Stop at 21m for 2:00 (32) on Nitrox 26.0, PPO2 0.802, END 19
Deep Stop at 15m for 2:00 (35) on Nitrox 26.0, PPO2 0.647, END 13
Norm Stop at 6m for 5:00 (41) on Nitrox 26.0, PPO2 0.415, END 5
Norm Stop at 3m for 20:00 (60) on Nitrox 26.0, PPO2 0.337, END 2

TOTAL DECO TIME: 31 minutes.
DIVE RUN TIME: 60 minutes.

3046.8 Ltr. of 26.0% consumed. Twin 12L
2843Ltr if you go on buddy s o2
and a run time of round 53 mins



The dive on the gas you have ie 21% and 65%
the 36% I just can’t find a purpose for it, on this dive ,
you could drop it to 100 bar and top off with air get a nice 3rd bottom gas
run a longer bottom time ie 35 mins and still stay in within your gas rules

Dive
Waypoint at 43m for 25:00 (26) on Air, PPO2 1.107, END 43
Deep Stop at 27m for 2:00 (29) on Air, PPO2 0.773, END 27
Deep Stop at 18m for 2:00 (32) on Air, PPO2 0.585, END 18
Waypoint at 15m for 2:00 (35) on Nitrox 65.0, PPO2 1.618, END 1
Deep Stop at 12m for 2:00 (37) on Nitrox 65.0, PPO2 1.425, END 0
Norm Stop at 6m for 2:00 (40) on Nitrox 65.0, PPO2 1.037, END 0
Norm Stop at 3m for 13:00 (53) on Nitrox 65.0, PPO2 0.844, END 0

TOTAL DECO TIME: 21 minutes.
DIVE RUN TIME: 53 minutes. Vytec over run +5 =58mins Vr3 ran at 55mins

2524.5 Ltr. of 21.0% consumed. Twin 12L
428.4 Ltr. of 65.0% consumed. 7 L cylinder
.
Bail out
Or buddy s 65% at 53nins

Waypoint at 43m for 25:00 (26) on Air, PPO2 1.107, END 43
Deep Stop at 27m for 2:00 (29) on Air, PPO2 0.773, END 27
Deep Stop at 21m for 2:00 (32) on Air, PPO2 0.648, END 21
Deep Stop at 15m for 2:00 (35) on Air, PPO2 0.523, END 15
Norm Stop at 9m for 1:00 (36) on Air, PPO2 0.398, END 9
Norm Stop at 6m for 10:00 (46) on Air, PPO2 0.335, END 6
Norm Stop at 3m for 26:00 (72) on Air, PPO2 0.273, END 3

TOTAL DECO TIME: 43 minutes.
DIVE RUN TIME: 71 minutes. Vytec over run + 9 = 80mins Vr3 ran at 75mins
3247.8 Ltr. of 21.0% consumed. Twin 12L
less if you get your buddy s 65%



The Vytec / VR3 over run, You would pull That Back as you deco on the fly
Vr3 deep stop 28m 0% Conservatism Zplan deep stop 27m on 10% Conservatism
DDplan 24m Deco planner 24m both on GFlo20% GFhi80%
So take your pick ,
I Think all the above meet your gas rules ,
bottom Rmv 16 deco Rmv 12 , My Rmv
Don’t know if you’ slurp or gulp the gas , so run your numbers ,

Hope this is of some help Have fun and enjoy your dive ,
,
Ps
Next time you see a pony don’t think it’s a donkey , it’s only a donkey when it’s full of 50% nitrox or less Ha I am in for it now,


Steve G,


Most days full sh:t as you can see .

[kjackoj]

Originally Posted by JohnD

below you will find the first dive I asked about planned on the PC using Zplanner. these runtimes will be laminated and carried along with alternate plans. for instance longer, deeper & bailout etc.

Waypoint at 43m for 25:00 (27) on Air, PPO2 1.107, END 43
Deep Stop at 27m for 2:00 (31) on Nitrox 36.0, PPO2 1.325, END 27
Deep Stop at 21m for 2:00 (33) on Nitrox 36.0, PPO2 1.111, END 21
Deep Stop at 15m for 2:00 (36) on Nitrox 36.0, PPO2 0.896, END 15
Norm Stop at 6m for 1:00 (43) on Nitrox 65.0, PPO2 1.037, END 6
Norm Stop at 3m for 12:00 (58) on Nitrox 65.0, PPO2 0.844, END 3

TOTAL DECO TIME: 19 minutes.
DIVE RUN TIME: 58 minutes.
CNS Total: 20.2%
OTU's: 57

Time to Fly: 3.0 Hours

3203.7 Ltr. of 21.0% consumed.
526.9 Ltr. of 36.0% consumed.
400.3 Ltr. of 65.0% consumed.
4130.9 Ltr. total open circuit gas consumed


why 36% & 65%? that Is all the O2 I could get out of the cylinders at clubhouse last night.......

I use the Vytec and had similar problems to Johns. I Emailed the boffins at Suunto and was told that the Vytec should not be used for deep stops, as any stop deeper than the ceiling will increase the stop time when you actually reach the ceiling. Apparently the ascent time is important and must be adhered to i.e. 10mts per minute. If you take longer to ascend your stop time at the ceiling will increase.
From my point of view the best way is as someone has already stated, use in gauge mode for deco dives and plan them with the V planner or similar.

Jacko

[gobfish1]

Originally Posted by kjackoj

I use the Vytec and had similar problems to Johns. I Emailed the boffins at Suunto and was told that the Vytec should not be used for deep stops, as any stop deeper than the ceiling will increase the stop time when you actually reach the ceiling. Apparently the ascent time is important and must be adhered to i.e. 10mts per minute. If you take longer to ascend your stop time at the ceiling will increase.
From my point of view the best way is as someone has already stated, use in gauge mode for deco dives and plan them with the V planner or similar.

Jacko

I think I will have to go with the boffins at suunto
Rather than the boffins on yd this time

[Garf]

Originally Posted by kjackoj

I use the Vytec and had similar problems to Johns. I Emailed the boffins at Suunto and was told that the Vytec should not be used for deep stops, as any stop deeper than the ceiling will increase the stop time when you actually reach the ceiling. Apparently the ascent time is important and must be adhered to i.e. 10mts per minute. If you take longer to ascend your stop time at the ceiling will increase.
From my point of view the best way is as someone has already stated, use in gauge mode for deco dives and plan them with the V planner or similar.

Jacko

This is because, unlike the VR3, the suunto computers do not credit you for the deep stops, they are still seen as being part of the bottom time rather than part of the ascent.