Need to practise making safe ascents & descents

[satwar]

I'm working on maintaining bouyancy control in 15-25 ft of water. If I mistakenly start floating up, and don,t catch it quickly, I will rapidly ascend to surface. I'm also concerned about falling too quickly.

Any suggestions on how I should be thinking about adding or dumping air from my wing to better control bouyancy during ascents and descents ? For example, using a quick tug on wing inflator hose makes recovery from an unintentional ascent very effective.

What should I be thinking and doing to make safe ascents and descents. I'd like to be able to stop at any depth during a descent or ascent. How do I learn this ?

 

[sabbath999]

Honestly, at 15 feet you shouldn't have much if any air in your wing.

At the end of your dive, you should have an empty wing at 15 feet with 500psi left in your tank and be able to control your buoyancy with your breathing if you are properly weighted.

When you put air in your wing or vent it, use TINY hits on your low pressure inflator or your dump. TINY.

 

[diver 85]

To me, you're over weighted--ie "falling too quickly" in 15 to 25 feet........

and, have some air trapped somewhere ie "mistakenly start floating up" in 15 to 25 feet........

 

[gcbryan]

It's just a matter of staying ahead of the curve. When descending just use a short tap of the inflator. If that doesn't work take a deep breath and only use another short tap if breath control isn't enough. You have to give it time to work.

Ascending is the same approach. Start deflating your BC with short taps before you really have to. It's a matter of anticipating. Make sure you can always stop where you are.

 

[satwar]

It's just a matter of staying ahead of the curve. When descending just use a short tap of the inflator. If that doesn't work take a deep breath and only use another short tap if breath control isn't enough. You have to give it time to work.

Ascending is the same approach. Start deflating your BC with short taps before you really have to. It's a matter of anticipating. Make sure you can always stop where you are.

How frequently are these short taps made ? Seems like things get out of control real fast.

 

[NC Wreck Diver]

I believe that you need to work on your weighting. Check your weight before a dive and after a dive (in a quarry or a pool). Use only enough for what you need to sink just below the surface, stay neutral at depth with minimal addition to your wing, and then at 15 feet. You should be able to get neutral at any depth. It's practice. But corking up is a problem. You say you don't realize this at times. Other than your gauges and surroundings, you ears are the key. You should be feeling minor changes as you change depth.

Good luck and safe diving to you.

 

[MXGratefulDiver]

The key to good buoyancy control is staying on top of it ... in other words, learning how to be proactive rather than reactive. As soon as you feel yourself starting to rise or sink, you need to do something about it right away. If you are properly weighted, this is best done using your breathing. Think of your lungs as another ... smaller ... BCD. If you are starting to rise, breathe out while you are reaching for that BCD hose. It may be all that's needed to help you get your buoyancy back under control ... but remember that once you breathe out you need to breathe back in again, so keep reaching for that BCD hose. If, when you breathe in, you find yourself rising again, let a small amount of air out of the BCD to stabilize your position.

Conversely, if you find yourself sinking, breathe in while you're reaching for that hose, and equalize with a small squirt of air into the BCD while you're breathing back out.

The reason most folks have issues with buoyancy control is that they wait too long to do something about it ... usually because they're fumbling around trying to find their BCD hose, or accidentally grabbing a snorkel thinking it's the inflator hose. And by the time you're in a position to add or remove air from the BCD, you've changed position sufficiently that you have to do something dramatic to get yourself back under control. Skip the drama ... think of your lungs as a "first defense" against buoyancy issues, and use them first. It's a much quicker response, and usually enough to get you back to where you want to be.

... Bob (Grateful Diver)

 

[Dave1981]

If it looks like you're starting to ascend unintentionally then fully exhale straight away and pause, it'll give you time to think. Control your buoyancy with your lungs. If your lungs need to be constantly empty to hold your depth then too much gas in your wing. If your lungs are constantly full to stay off the bottom then add some gas.

If you're slowly ascending or descending your breathing to hold that rate should be an advance indication of what's happening. it's best to do this following a bank to begin with, or failing that an upline that you can reference your rate on.

 

[danvolker]

In addition to the weighting tips you have already heard, I would recommend swimming in a spiral/ circle around the line or your buddies while at the 15 foot stop...as you slowly swim around in the circle, your horizontal movement will make it much easier to hold a precise depth--like the wings of an airplane hold it at an altitude when circling the airport.
Another bonus is better off gassing with a horizontal body position, and the very slight exertion(as opposed to zero exertion of just hanging without movement).
DanV

 

[PatW]

Bouyancy control at 15' is kind of tough.

I generally empty my BC before I ascend. This habit also means that there is no air in my BC to expand as I rise which could accellerate the ascent. With my tank low on air, I should be very close to neutrally bouyant.

As people above have stated, your lungs are another BC. Inhaling and exhaling with affect your bouyancy. The thing that makes all of this trickier is that there is a lag time between exhaling and starting to drift down.

Another thing that is tricky is if you are in an empty column of water. It is a bit hard to keep track of how deep you are (unless you keep your eyes glued to your depth gauge) especially if you are like me and like to gawk at things on your safety stop. It is nice to have a depth reference point like the mooring line. Just check the reference point every now and then to be sure that you have not wandered out of your depth. On a 15' safety stop, it is easy to drift too shallow (10') or too deep (20').