hi all just a quick one I'm about 50 dives In am a rescue diver so I think an basic skill set is there enough ,I currently dive with a sunnto steel when ever finishing a dive I always swim up , ensure my bcd Is deflating the whole time not rising quicker than bubbles but every dive I do my computer logs ascent speed warnings , I really don't feel it's me because I will be sitting neutral give one kick and the ascent bar goes from 0-100% and not even risen half a metre I'm not sure if it comes back to the conservative algorithm of sunnto , maybe it's partly my fault but going off other divers, bubbles and my total ascent time I really don't feel I'm 100% to blame
Ascent Help
- Thread starter SLATSY
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Michael Guerrero
Contributor
If you're making reasonable ascents I wouldn't sweat it. But what Sloth said is correct as far as technique.
Slatsy,
I'm going to teach you a new way of doing this. If you can use it, great, if not. no worries.
My technique will allow you to control your ascent rate and to keep it (at average) exactly pinned to 10m per minute. This is the same technique I teach in my OW course and the same technique I use during all of my own dives, including staged decompression dives.
What you need to do this is (a) your depth and (b) your time.
The ascent goes like this: Suppose we're making a dive to 30m and we planned to leave the bottom with 5 min of NDL to spare.
What you'll do is start watching your clock when your NDL hits 6 min. Suppose your clock says 14 minutes at that point. As soon as your clock flips to 15 minutes your time is "synchronised" with your depth and it's time to start ascending. You swim up from 30m to 20m at what "feels" like the right pace. You can use any cues you want for that. Normally I watch bubbles.
Once you get to 20m you STOP for moment and look at your clock. If you have ascended at exactly 10m per min then your clock will flip to 16min as soon as you get to 20m. Most of the time, however, that does not happen. Your clock will either already show 16 (or maybe even more) or your clock will still show 15 as it did at the bottom.
If your clock already shows 16 (or more) then just roll through the 20m depth and continue to ascend to 10m.
If your clock still shows 15 then WAIT at 20m until it flips to 16 minutes and then resume ascending to 10m.
Do the same thing at 10m before ascending to 5m. At 10m your "perfect" ascent will flip to 17min. If it's more, then just continue on to 5m. If it's less than 17 then WAIT at 10m until it flips to 17m and then go to your safety stop.
On average this will allow for an ascent of exactly 10m per min.
You can, of course, use this same technique for ascents at different speeds. For example, in the shallower parts of an ascent from a deco dive we use 3m per min and you can use your clock and your depth in exactly the same way.
Keep in mind that even though you can choose any ascent rate you want using this technique, you shouldn't ascend from a dive at much faster than 10m per min or much slower than 3m per min. Faster you already understand but If you ascend much slower than 3m per min then you do run a good chance that your NDL will continue to drop to zero (or below).
Does that help at all?
R..
I'm going to teach you a new way of doing this. If you can use it, great, if not. no worries.
My technique will allow you to control your ascent rate and to keep it (at average) exactly pinned to 10m per minute. This is the same technique I teach in my OW course and the same technique I use during all of my own dives, including staged decompression dives.
What you need to do this is (a) your depth and (b) your time.
The ascent goes like this: Suppose we're making a dive to 30m and we planned to leave the bottom with 5 min of NDL to spare.
What you'll do is start watching your clock when your NDL hits 6 min. Suppose your clock says 14 minutes at that point. As soon as your clock flips to 15 minutes your time is "synchronised" with your depth and it's time to start ascending. You swim up from 30m to 20m at what "feels" like the right pace. You can use any cues you want for that. Normally I watch bubbles.
Once you get to 20m you STOP for moment and look at your clock. If you have ascended at exactly 10m per min then your clock will flip to 16min as soon as you get to 20m. Most of the time, however, that does not happen. Your clock will either already show 16 (or maybe even more) or your clock will still show 15 as it did at the bottom.
If your clock already shows 16 (or more) then just roll through the 20m depth and continue to ascend to 10m.
If your clock still shows 15 then WAIT at 20m until it flips to 16 minutes and then resume ascending to 10m.
Do the same thing at 10m before ascending to 5m. At 10m your "perfect" ascent will flip to 17min. If it's more, then just continue on to 5m. If it's less than 17 then WAIT at 10m until it flips to 17m and then go to your safety stop.
On average this will allow for an ascent of exactly 10m per min.
You can, of course, use this same technique for ascents at different speeds. For example, in the shallower parts of an ascent from a deco dive we use 3m per min and you can use your clock and your depth in exactly the same way.
Keep in mind that even though you can choose any ascent rate you want using this technique, you shouldn't ascend from a dive at much faster than 10m per min or much slower than 3m per min. Faster you already understand but If you ascend much slower than 3m per min then you do run a good chance that your NDL will continue to drop to zero (or below).
Does that help at all?
R..
Using the "smallest bubble" would always result in too fast ascents for me as well. I checked and it seems (I don't have the reference) that even small bubbles ascend at about 50 feet/minute. Remember too that as they ascend they expand and travel faster. So if you use this guide, you may want to go a little slower then the smallest and reorient to new "smallest bubbles" as you ascend.
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what she said, bubbles rise a lot faster than you are supposed to. watch the computer and follow that
Kharon
Contributor
I was taught to remain neutral during the entire ascent and use breathing to go up while bleeding the BC slightly to remain neutral. I've found that seems to work. Also taught to ascend in a horizontal position rather than vertical.
Where's your computer? On your wrist or a console?
(I also breathe myself up in a horizontal position)
(I also breathe myself up in a horizontal position)
Right wrist. (When I did my Prism training the unit came set up for the controller on the left, and my instructor couldn't figure out why I was always looking at the back-up Petrel on the right instead of the controller.)
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