Bouyancy issue - what happened to me?

[The_DivePirate]

As stated above, the problem was probably lung pump. When I work at the Oregon Coast Aquarium I find the becoming an issue in the exhibits, I have too go to my place of zen, and remember too breath calmly. If you are taking larger breaths than you are exhaling you become positive. Remember that scuba is too be relaxing, not a race! If you encounter that your dive buddy is leaving you behind continously, mention too them that they are doing so, and ask if they may slow their pace. It's not always avoidable, but if you keep in mind it can happen, you will have a better chance of overcoming the issue. If, you actually had NO air in your BC at depth and were in a wetsuit I would actually add a couple of pounds, not enough that makes you add so much air in your BC that you feel uncomfortable, because sometimes you may not always the same tank available and some will react differently. Remember you can always dump some air, only if air is available too dump. That way, if you have the same issue again, you will have some air too dump. I suggest, in a controlled enviorment, play with your bouyancy. Get yourself neutral, take a large breath of air, pause(not holding your breath:no, just pausing!!) and see the effects. You will see that you that you will raise in the water column, then exhale. Then get neutral again, and take a large exhale, you should become negative. Experiment with this exercise, it will be advantagious too your diving when you just want too raise or lower yourself a few feet in the water column. Just remember that diving is supposed too be fun!!! Good luck in your advancement, and congrats on your new accomplishments/addiction!!!
Joe

 

[Doc Harry]

Just another thought- what were you wearing?

I found that when I was neutrally buoyant and wearing 5mm or 7mm neoprene, even a slight ascent caused the neoprene to expand, causing me to rise further, causing the neoprene to expand further, etc., and up I went.

Thicker neoprene wetsuits make buoyancy control more difficult than it has to be. (I switched to a dry suit.)

 

[cyoung]

I believe the previous info (lung pumping) is going to be the culpret, or at least a large part of it. Its somewhat common for most divers to be a "little" overweight. I'm not talking about 10# or more, just a little extra to offset, or help offset a buoyancy problem.

Next time you're at the lake, take 6-8# of extra weight with you.

At the begining, make your way over to the platform, drop the extra weights on the platform. Then go on and dive at your liesure, depleting your gas down to around a 1000# or so. Head back over to the platform.

Hopefully, the platform has a rail or something you can grab hold of in case you start to rise. With your BC empty, begin to calm yourself, relax, slow, even breathing - try and attain a nuetral buoyancy, not touching the platform, sort of suspend just above it.

Take a really deep breath. Remember to exhale immediately if you start to rise. If you started to rise suddenly, exhale - grab hold of something to help stop your ascent.

Add 4#, 2# on each side (pocket), repeat. This time did you suddenly begin to rise, or slowly. Slowly, add 2#, try and stick it in the center between your cumber band and waist strap. Now, try again. I believe you get the gist of trimming yourself out.

A "Little" overweight is not harmful, to much overweight can be. Please stay within the 6-8# extra.

Now, if you change anything in your gear lighter/heavier wetsuit, larger tanks, negative vs positive fins, these changes will also affect your buoyancy.

In the begining, few new divers are immune to buoyancy problems, and if one is lucky, finds a mentor (an advanced N good diver) to help overcome some of our newbie problems.

Dive safe, enjoy moment........hope this is/will be helpful.

Carl

 

[pipedope]

You were excited and probably not doing a full exhale.

When you find this happening again just remind yourself to exhale fully and inhale fully slowly and calmly and see how fast the problem goes away.

You will develop the ability to keep a calm body with calm breathing and yet have an excited mind having fun underwater.

 

[TSandM]

The key pieces of information are that you got positively buoyant, and that, without any intervention whatever on your part, the problem went away. To get positive, you either have to add air to something, expand the air in something, or lose something negative. If you added air, or lost a weight, or had consumed enough gas to be positive, you would have HAD to change something to return to neutral. Since you didn't change anything you were aware of, it almost had to be the air in your lungs causing the problem.

I don't know what was going on in the dive when you got positive, but if you were doing something at all task-loading -- checking gauges, adjusting equipment, using a light or a camera -- it is very easy to lose track of the steady, even rhythm of your breathing. One of the things we all had to learn in Fundies was how to be task-loaded without losing buoyancy control, and most of us were really bad at it to begin with. It's quite possible to cork all the way to the surface over something as simple as clearing a mask while hovering, when you aren't used to doing it.

In addition, when I was new at diving, it was easy for me to miss the first signs of being off neutral buoyancy. I wouldn't realize I was light (or heavy) until my depth had changed by several feet, which was enough for the pressure differential to begin to accelerate the change. I found it very helpful to stop finning every thirty seconds or so, just for a short time, and see if I rose or fell. Then I could adjust my buoyancy to stay neutral. NWGratefulDiver also told me, during that novice period, that it was a real good idea to stay close to the bottom. If you are six inches off the bottom, and rise six inches, you'll notice it. If you're six FEET off the bottom, and rise six inches, or a foot, or even two feet, you may not notice the difference, but especially if you are shallow, it may be enough to begin a self-perpetuating process that requires some urgent intervention to stop.

 

[lmorin]

.......I started to float up a bit. I tried to let air out of bc- didn't help. I thought well maybe, since I am nose down trying not to ascend, the air is stuck in the bottom of the bladder- so I tried letting it out of the bottom valve. Nothing. I even reached back to try and feel any air in the bladder- felt no air.
Any way, I swam my a$$ off to get back down. After a few minutes the problem, whatever it was, ceased to exist.......

When I first started diving, this sort of thing happened to me about 3-4 times. My wife and I would be swimming along, then I would disappear out of her sight, floating upward. She'd see me frantically trying to let air out of my BC, but to no avail, as there was nothing to let out. I never did figure out exactly why these up-ticks happened, but they were almost certainly caused by improper breathing. I was an air hog and had no concept of deliberately controlling my ascents/descents just with my lungs. Around dive 25 or so, that really changed (also did AOW that included peak performance buoyancy at about this time). My air efficiency rapidly came closer to that of my wife who breathed properly from the outset. I've not had an "uptick" in over 75 dives since.

 

[cowdog77]

It helps to breathe "off the bottom" of your lungs to descend and breathe "off the top" when wanting to ascend.

If you completely exhale, don't inhale a large full gasp/breath...instead, draw in perhaps a quarter breath.

Will help alleviate the yo-yo effect and can become a great fine-tuner.

 

[1_T_Submariner]

You have already recieved some great advice and diagnoses. The only thing I would like to add is disscuss with your Partner/buddy what happened and ask him/her to look at your bc bladder if this happens (tell them what you want them to look for and how to signal them). This happened with my wife. She couldn't find the air by feeling and she was not in the right position to get it out.

It's not likely this is your problem as others have said just bringing up the point that sometimes the air trapped is hard to find by yourself.

 

[maremd50]

"we were swimming with the terrain which had us yo-yo-ing about 5 ft either way

I started to float up a bit.

Any way, I swam my a$$ off to get back down. After a few minutes the problem, whatever it was, ceased to exist."



This same type of thing happened to me when I was in Puerto Vallarta, diving in an area with lots of ups and downs over the terrain, and not too deep (about 25 ' 30 ft I think). I just started rising, and had to dump all my air to get back down. Once I was down, then I added air to keep me off the bottom. It was weird. I'm only 8 dives into this sport, so I am still trying to learn BC. I feel like such a clutz! I really want to get this right!!!! I was wearing a 7mm wetsuit. The comment about BC being more difficult to control at shallower depths and with thick wetuits helped clarify for me that those factors figured into the experience. I love this Board - I am learning SO MUCH - can't wait to get under water again and put it to use.

 

[hollywood703]

without any other information, here would be some of my possibles.....

....increased bouyancy from the tank pressure which was compounded by full lung capacity and possibly the increased bouancy of the wetsuit as you started to rise from the tank pressure and the lungs

If properly weighted, and using very relaxed slow longer breath's, you should rise slightly on inhale, and fall slightly on exhale.

When you start to notice you are rising, it is important to work efficiently to solve the problem as the more you rise, the atmosphere change will speed up the ascent. The even trace amounts of air in the BC will become larger, the Neoprene will expand causing faster ascent, and even lung capacity will get larger.......conversely, the deeper you go, the faster you will descend if you dont adjust.

Here is a trick i do, and it might help you.....
When i start putting together my equipment.....I start with as empty a BC as I can.....then i walk into 3 ft of water and check my weighting Adjust weights until at this level with no other correction, i rise and fall based on my breathing alone. This way, when i add the weight that im going to need at the end of the dive, I should be perfectly weighted. I also document the exact equipment that I am using, and make a note of the weight, this way next time I go, I will be very close to where i need to be.

Now as you dive more, you will be able to remove some weight, but for now...this is a practice I would recommend. If you are diving aluminum 80 you will need to add about 4 lbs to account for end dive tank bouyancy....so figure out what you need full using method above, then add 4 lbs and you should be golden....

I like to be a few pounds heavy as Im using a drysuit and trapped air is common, so i add more weight if using the drysuit. I have plenty of lift between my bc and my drysuit to counteract the weight.