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Why would you have to swim up? Not much of a controlled ascent is it.

While not my acent of choice most times, it can be a very controlled acent. If you are slightly negative and vary your finning properly, you can go from slightly decending to a fast accent and everything in between very quickly and with easier control than using a neurtal breath control acent. It's a good choice when following students and you may need to change directions quickly to catch a runaway student.
 
Why would you have to swim up? Not much of a controlled ascent is it.

Why not? I've been doing a swimming ascent since way before BCs were even used. Although I now wear a BC (because some places require it) I don't use it underwater. The only time I put air in it is at the surface.
 
Why not? I've been doing a swimming ascent since way before BCs were even used. Although I now wear a BC (because some places require it) I don't use it underwater. The only time I put air in it is at the surface.

The OP asked about slow ascents. I suspect your slow ascents are a lot faster than mine. I'm not going to swim up if it is going to take 6 minutes to ascend the last 30 feet, which is what most of my repetitive dives look like. But a lot of this is habit. I have not used anything but the rear dump valve for years which favors being horizontal. Certainly being horizontal presents more surface area to the water in the direction of travel and that will slow you down. It's a different approach than the five point ascent taught in ow classes.
 
I suppose the "best" way to ascend really boils down to personal preferences. I have been doing the traditional vertical swimming ascent for around 46 years now. For me, it's the simplest and easiest way to get to the surface. I weight myself to be neutral at the surface with a low tank and look up toward the surface and watch my bubbles as I ascend, going slower than my slowest bubbles.

I've never developed the safety stop habit and I still dive using Navy dive tables. All my dives are within the NDLs according to the tables. I have a computer, but I keep it in gauge mode and use it in parallel with a watch and capillary depth gauge.

I know that this is not the method taught in today's tech dependent dive schools, but it works for me and for the kind of diving I do.
 
Just in case the OP is wondering about measuring his ascent rates, many computers have an ascent rate scale (as well as current depth) on them. This is one of the advantages to a wrist style computer, it is easier to have control of your BCD & look at your computer & still keep your buddy within sight during ascents and safety stops.
 
Yes two different approaches. Slowing down should make fewer bubbles, but staying away from your NDL prevents there being very much gas in solution in the first place to bubble. It may be worth trying both if you feel fatigued after your dives.
 
OK, I am a little confused here. We have many experienced divers ascending two different ways.
A few newbie questions: Which is safer? Which should I practice more? Is one better than the other?
My instructor pointed out that the kicking ascent is used because you always (try to) stay slightly negative which leaves you, not the BC, in ultimate control of your ascent.
To the OP; great question!
Get Wet!
 
OK, I am a little confused here. We have many experienced divers ascending two different ways.
A few newbie questions: Which is safer? Which should I practice more? Is one better than the other?
My instructor pointed out that the kicking ascent is used because you always (try to) stay slightly negative which leaves you, not the BC, in ultimate control of your ascent.
To the OP; great question!
Get Wet!

Slightly negative...I guess during my ascents I am slightly negative in the fact that I have to take a deep breath to ascend but will descend with a "pause" of about 50% breath.

One of the easiest ways to learn to control your ascent is to have a line and mark every foot on it. Then just practice your ascent using a visual reference. If you start going too fast or the wrong direction, you have the line to help square you up again.

During recreational diving well within your NDL's I don't think one would be better than the other. However, if you start tech diving, you want to remain horizontal as much as possible during the ascent because the theory is that you off-gas better in the horizontal position.
 
Posts 6 & 7 cover the whole show on how to get to the surface the right way. A little trick an extremely experienced diver taught me early on is to watch the scatter. No matter where you are diving, except maybe a pool, there are minute particles right in front of you, they're everywhere. The thing about scatter is that it's not going anywhere quickly. If you're not sure of how fast you're moving, up or down, look to the scatter to tell you & if you're going up too fast, dump some air to make things right.
 
OK, I am a little confused here. We have many experienced divers ascending two different ways.
A few newbie questions: Which is safer? Which should I practice more? Is one better than the other?
@stakanak: Although I'm in the ascend-using-breath-control-at-near-neutral-buoyancy camp, I can imagine certain situations when it might be prudent to ascend while being slightly negatively buoyant, e.g., buddy forgot to bring enough lead, boat traffic at surface, etc.

No method is 100% "safe." How many times have you found yourself holding your breath during strenuous exertion? If a diver is severely negatively buoyant and kicking hard to ascend, inadvertent breath-holding would increase the possibility of cerebral arterial gas embolism.

I'd recommend trying both methods of ascending to figure out which method feels more comfortable for you. Contrary to what some people might write here on SB, there is no scuba police.
My instructor pointed out that the kicking ascent is used because you always (try to) stay slightly negative which leaves you, not the BC, in ultimate control of your ascent.
That's not a very convincing explanation. First, staying negatively buoyant during an ascent is going to make ascending more of a work-out than it needs to be. It also begs the question how the diver should maintain depth during a safety stop. Is he supposed to kick all of the time? I do longer safety stops and forcing myself to kick for 7-10 minutes straight is kind of ridiculous. Second, buoyant forces play a role during all phases of the dive, including the ascent. The diver is the one responsible for operating his BCD, so there is no abdication of ascent control to the BCD itself. The BCD is just a tool...it's not an unruly beast that you're riding to the surface.

I would have understood if your instructor said that, for newer divers who don't have the best buoyancy control, it might be safer to stay slightly negatively buoyant during the ascent to protect against an uncontrolled ascent. All the diver has to do is stop kicking and he'll sink. But he didn't say that, did he? :shakehead:
 
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