This profile raised questions comments about how long it was etc etc. I found this odd as I did the ratio in my head for the dive and the ascent time was about the same as the computer was asking for.
So I thought id put up this comparison between what my computer spat out and what DOTF works out (by my understanding).
The actual profile asked for by the computer was as follows:
2 @ 27
2 @ 24
2 @ 21
2 @ 18
4 @ 15
6 @ 12
9 @ 9
28@ 6
Including ascent times total deco running 10/85GF was 62mins
I ran it through Deco on the fly and came up with: 47mins @ 47m
1 @ 36
1 @ 33
1 @ 30
1 @ 27
1 @ 24
5 @ 21
4@ 18
3 @ 15
3 @ 12
10 @ 9
26 @ 6
I make this a total 62min ascent
If you ignore the decent time then it was a 42min bottom time avg depth 47m
1:1 ratio based on 45m so add 5mins = 47mins deco
so
1 @ 36
1 @ 33
1 @ 30
1 @ 27
1 @ 24
5 @ 21
4 @ 18
3 @ 15
3 @ 12
9 @ 9
24 @ 6
Total 59mins deco ascent.
As it was we did an extra 10mins deco to clear the VR3. Now i beleive the reasion for this was Howards VR3 would have been running something like 1.25 fixed set point and would asume Helium in the mix all the way to the surface. My computer was plumbed into the unit so it took my actual PP02 inot account including the Helium free time spent on 100% at 6m
If we look at Vplanner for a 1.25 setpoint profile with He in the mix it comes out at this:
Decompression model: VPM - B
DIVE PLAN
Surface interval = 5 day 0 hr 0 min.
Elevation = 0m
Conservatism = + 2
Dec to 47m (3:08) Diluent 21/50 1.25 SetPoint, 15m/min descent.
Level 47m 43:52 (47:00) Diluent 21/50 1.25 SetPoint, 11m ead, 19m end
Asc to 27m (51:00) Diluent 21/50 1.25 SetPoint, -5m/min ascent.
Stop at 24m 1:00 (52:00) Diluent 21/50 1.25 SetPoint, 0m ead, 10m end
Stop at 21m 1:00 (53:00) Diluent 21/50 1.25 SetPoint, 0m ead, 9m end
Stop at 18m 3:00 (56:00) Diluent 21/50 1.25 SetPoint, 0m ead, 8m end
Stop at 15m 4:30 (60:30) Diluent 21/50 1.25 SetPoint, 0m ead, 7m end
Stop at 12m 5:00 (65:30) Diluent 21/50 1.25 SetPoint, 0m ead, 6m end
Stop at 9m 7:30 (73:00) Diluent 21/50 1.25 SetPoint, 0m ead, 5m end
Stop at 6m 30:30 (103:30) Diluent 21/50 1.25 SetPoint, 0m ead, 4m end
Surface (105:30) Diluent 21/50 -3m/min ascent.
If we asume 100% 02 at the 6m stop it looks like this:
Decompression model: VPM - B
DIVE PLAN
Surface interval = 5 day 0 hr 0 min.
Elevation = 0m
Conservatism = + 2
Dec to 47m (3:08) Diluent 21/50 1.25 SetPoint, 15m/min descent.
Level 47m 43:52 (47:00) Diluent 21/50 1.25 SetPoint, 11m ead, 19m end
Asc to 27m (51:00) Diluent 21/50 1.25 SetPoint, -5m/min ascent.
Stop at 24m 1:00 (52:00) Diluent 21/50 1.25 SetPoint, 0m ead, 10m end
Stop at 21m 1:00 (53:00) Diluent 21/50 1.25 SetPoint, 0m ead, 9m end
Stop at 18m 3:00 (56:00) Diluent 21/50 1.25 SetPoint, 0m ead, 8m end
Stop at 15m 4:00 (60:00) Diluent 21/50 1.25 SetPoint, 0m ead, 7m end
Stop at 12m 5:30 (65:30) Diluent 21/50 1.25 SetPoint, 0m ead, 6m end
Stop at 9m 7:00 (72:30) Diluent 21/50 1.25 SetPoint, 0m ead, 5m end
Stop at 6m 9:30 (82:00) Oxygen 1.60 ppO2, 0m ead
Stop at 3m 15:00 (97:00) Oxygen 1.30 ppO2, 0m ead
Surface (98:00) Oxygen -3m/min ascent.
Whilst the Vplanner profiles are nothing like the VR3 profiles this demontrates how much diference it makes leaving He in the mix. It adds 7mins to the dive. Howards VR3 added 8.
I am interested to see what others make of the actual profile? WOuld you do something diferent with the DOTF? i know that at set point and just above the DPTF 1:1 ratio is very conservitave but do you taylor the deco with this in mind or do yo do the same adjustments on all DOTF profiles?
ATB
Mark Chase
So I thought id put up this comparison between what my computer spat out and what DOTF works out (by my understanding).
The actual profile asked for by the computer was as follows:
2 @ 27
2 @ 24
2 @ 21
2 @ 18
4 @ 15
6 @ 12
9 @ 9
28@ 6
Including ascent times total deco running 10/85GF was 62mins
I ran it through Deco on the fly and came up with: 47mins @ 47m
1 @ 36
1 @ 33
1 @ 30
1 @ 27
1 @ 24
5 @ 21
4@ 18
3 @ 15
3 @ 12
10 @ 9
26 @ 6
I make this a total 62min ascent
If you ignore the decent time then it was a 42min bottom time avg depth 47m
1:1 ratio based on 45m so add 5mins = 47mins deco
so
1 @ 36
1 @ 33
1 @ 30
1 @ 27
1 @ 24
5 @ 21
4 @ 18
3 @ 15
3 @ 12
9 @ 9
24 @ 6
Total 59mins deco ascent.
As it was we did an extra 10mins deco to clear the VR3. Now i beleive the reasion for this was Howards VR3 would have been running something like 1.25 fixed set point and would asume Helium in the mix all the way to the surface. My computer was plumbed into the unit so it took my actual PP02 inot account including the Helium free time spent on 100% at 6m
If we look at Vplanner for a 1.25 setpoint profile with He in the mix it comes out at this:
Decompression model: VPM - B
DIVE PLAN
Surface interval = 5 day 0 hr 0 min.
Elevation = 0m
Conservatism = + 2
Dec to 47m (3:08) Diluent 21/50 1.25 SetPoint, 15m/min descent.
Level 47m 43:52 (47:00) Diluent 21/50 1.25 SetPoint, 11m ead, 19m end
Asc to 27m (51:00) Diluent 21/50 1.25 SetPoint, -5m/min ascent.
Stop at 24m 1:00 (52:00) Diluent 21/50 1.25 SetPoint, 0m ead, 10m end
Stop at 21m 1:00 (53:00) Diluent 21/50 1.25 SetPoint, 0m ead, 9m end
Stop at 18m 3:00 (56:00) Diluent 21/50 1.25 SetPoint, 0m ead, 8m end
Stop at 15m 4:30 (60:30) Diluent 21/50 1.25 SetPoint, 0m ead, 7m end
Stop at 12m 5:00 (65:30) Diluent 21/50 1.25 SetPoint, 0m ead, 6m end
Stop at 9m 7:30 (73:00) Diluent 21/50 1.25 SetPoint, 0m ead, 5m end
Stop at 6m 30:30 (103:30) Diluent 21/50 1.25 SetPoint, 0m ead, 4m end
Surface (105:30) Diluent 21/50 -3m/min ascent.
If we asume 100% 02 at the 6m stop it looks like this:
Decompression model: VPM - B
DIVE PLAN
Surface interval = 5 day 0 hr 0 min.
Elevation = 0m
Conservatism = + 2
Dec to 47m (3:08) Diluent 21/50 1.25 SetPoint, 15m/min descent.
Level 47m 43:52 (47:00) Diluent 21/50 1.25 SetPoint, 11m ead, 19m end
Asc to 27m (51:00) Diluent 21/50 1.25 SetPoint, -5m/min ascent.
Stop at 24m 1:00 (52:00) Diluent 21/50 1.25 SetPoint, 0m ead, 10m end
Stop at 21m 1:00 (53:00) Diluent 21/50 1.25 SetPoint, 0m ead, 9m end
Stop at 18m 3:00 (56:00) Diluent 21/50 1.25 SetPoint, 0m ead, 8m end
Stop at 15m 4:00 (60:00) Diluent 21/50 1.25 SetPoint, 0m ead, 7m end
Stop at 12m 5:30 (65:30) Diluent 21/50 1.25 SetPoint, 0m ead, 6m end
Stop at 9m 7:00 (72:30) Diluent 21/50 1.25 SetPoint, 0m ead, 5m end
Stop at 6m 9:30 (82:00) Oxygen 1.60 ppO2, 0m ead
Stop at 3m 15:00 (97:00) Oxygen 1.30 ppO2, 0m ead
Surface (98:00) Oxygen -3m/min ascent.
Whilst the Vplanner profiles are nothing like the VR3 profiles this demontrates how much diference it makes leaving He in the mix. It adds 7mins to the dive. Howards VR3 added 8.
I am interested to see what others make of the actual profile? WOuld you do something diferent with the DOTF? i know that at set point and just above the DPTF 1:1 ratio is very conservitave but do you taylor the deco with this in mind or do yo do the same adjustments on all DOTF profiles?
ATB
Mark Chase