terri
Guest
So far, I have never had this experience. And reading your posts will probably raise my already,'top of the mind awareness' while down. Glad there are divers out there like you sharing information, just makes us better, and safer.
uncontrolled ascent
- Thread starter appleofthesea
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Appleofthesea-You gotten some great advice, it's all good. Do you own your own BC,if so why don't run it by your LDS and have the inflator mech. checked, it might be a long shot but one way that they fail is to trickle air in constantly adding air when you don't know it. Also I have a way of making ascents that might help you. Break the ascent down into 10 foot "stops" Suppose your at 60 ft You and your buddy, TOGETHER, SLowly swim up to 50 ft, it should take AT LEAST 10 seconds, if you get to 50ft in less than 10 sec. than slow down and try to spend at least 10 seconds to swim up to 40. Try to stop at each 10ft increment and check in with your buddy and check the time. When you reach 30ft your going to slow down even more. Try to spend at least 20-30 seconds slowly swimming up to your 15ft safety stop. When you arrive at 15 ft check eack other check time check air supply. Practice staying at 15 ft WITHOUT kicking, try to stay at 15 ft by using good nuetral bouyancy control and preferably remain horizontal in the water. Try this next time you dive. It may help your you control your ascent and slow your ascent AND your bouyancy Dive Safe-Dive Alot-M
OP
appleofthesea
Guest
I think that the BC is ok.
I think I have figured out the problem. When I was first certified I was overweighted so I could get down. Since then I have dropped 5 lbs from my weightbelt. Well, on that dive I had tried to drop two more pounds.
I went diving again with the same weight (24 lbs, but with 2 piece wetsuit). At the end of the dive it took me a lot of effort to stay down at around 10-15 feet. If I mostly exhaled maybe I can stay down, but the bc is totally empty at that point and if there was a little air left in it then I have to fin to stay down. I was trying to do a proper buoyancy check (as learned on the scubaboard), and this seems to be the key. Even descending I had to use my arms or kick a tiny bit to get below (I didn't sink easily just by exhaling). It wasn't hard to get down but after my al80 was down to 500 psi I guess the weight change was enough to mess me up at the end.
So I am thinking I'll go back up to 26lbs. Maybe 25 would be ok, but it is harder for me to balance an add number of lbs and I am tired of buying weights and taking them back. Is 26lbs an unreasonable amount of weight? I am about 6'0 175lbs.
Now I can say I am a lot more aware of my buoyancy and I have been practicing the tips I have been given in this thread.
Happy diving!
I think I have figured out the problem. When I was first certified I was overweighted so I could get down. Since then I have dropped 5 lbs from my weightbelt. Well, on that dive I had tried to drop two more pounds.
I went diving again with the same weight (24 lbs, but with 2 piece wetsuit). At the end of the dive it took me a lot of effort to stay down at around 10-15 feet. If I mostly exhaled maybe I can stay down, but the bc is totally empty at that point and if there was a little air left in it then I have to fin to stay down. I was trying to do a proper buoyancy check (as learned on the scubaboard), and this seems to be the key. Even descending I had to use my arms or kick a tiny bit to get below (I didn't sink easily just by exhaling). It wasn't hard to get down but after my al80 was down to 500 psi I guess the weight change was enough to mess me up at the end.
So I am thinking I'll go back up to 26lbs. Maybe 25 would be ok, but it is harder for me to balance an add number of lbs and I am tired of buying weights and taking them back. Is 26lbs an unreasonable amount of weight? I am about 6'0 175lbs.
Now I can say I am a lot more aware of my buoyancy and I have been practicing the tips I have been given in this thread.
Happy diving!
Apple,
It's good to hear you've survived your experience. Congratulations! you have just learned that your C-card is not just a certification card, but also a license to learn.
Something like that also happened to me in Cozumel, but it wasn't from 55 feet; I had been to 110' and on ascent I also experienced a runaway ascent situation. One thing that saved me was that I had read some of the tips in Scuba Diving's Dive like a pro booklet. Ok, so many people don't swear by it, but I believe anything that helps you should be classified as credible. The tip that immediately came to mind was to flare my ascent, which involved arching my body backwards and spreading my arms and legs so as to cause more drag. Luckly for me I didn't get bent.
One thing that I'm curious about, and up front, no pun intended; you say you're now using about 24 lbs to dive and that you had cut back about 5 lbs. Are you using a 5 or 7 mil wetsuit? A dry suit? If you're not, and you're of average built, you may be using too much weight, which can come as a result of not dumping all the air out of your bc, or perhaps using an exposure suit that fits loose and traps air.
Your wetsuit (if that's what you're using) should fit like a glove, tight enough to make you work sliding it on, but not so tight that it constricts your breathing. Also, in another post, someone mentioned using the pull-to-dump feature of the power inflator on your bc. I tell you why that's the best way to dump air all the time; it is a one way valve, meaning, if you were to dump all the air and continue pulling the hose as if to dump more, no water would enter your bc. On the other hand, by dumping air out of your manual inflator button, once all the air is out of your bc, water gets in, which not only ruins the inside of your bladder, it can cause you to be more negatively buoyant. One more benefit of the pull-to-dump, if you're in a heads up attitude, the dump is always the highest point, so no risk in not dumping air due to holding a power inflator too low, especially if the velcro that secures the power inflator to your bc is low on the shoulder pad.
Here is something that, at least for me, has been of great help in determining weight:
http://dive.scubadiving.com/html/200105buoyancycalc_chart.html
One last point; don't beat yourself up. You seem to be a perfectionist, which is good (I am too), but don't forget the most important law of learning, the law of practice and drill, which states that "things most often repeated are best remembered." (from the flight instructor's fundamentals of instructing handbook)
Learn from your experience and do your best to be aware it can happen at any time so stay ahead of the ascent and anticipate it. And by all means, Dive Dive Dive!!!
Semper safe
Rick
It's good to hear you've survived your experience. Congratulations! you have just learned that your C-card is not just a certification card, but also a license to learn.
Something like that also happened to me in Cozumel, but it wasn't from 55 feet; I had been to 110' and on ascent I also experienced a runaway ascent situation. One thing that saved me was that I had read some of the tips in Scuba Diving's Dive like a pro booklet. Ok, so many people don't swear by it, but I believe anything that helps you should be classified as credible. The tip that immediately came to mind was to flare my ascent, which involved arching my body backwards and spreading my arms and legs so as to cause more drag. Luckly for me I didn't get bent.
One thing that I'm curious about, and up front, no pun intended; you say you're now using about 24 lbs to dive and that you had cut back about 5 lbs. Are you using a 5 or 7 mil wetsuit? A dry suit? If you're not, and you're of average built, you may be using too much weight, which can come as a result of not dumping all the air out of your bc, or perhaps using an exposure suit that fits loose and traps air.
Your wetsuit (if that's what you're using) should fit like a glove, tight enough to make you work sliding it on, but not so tight that it constricts your breathing. Also, in another post, someone mentioned using the pull-to-dump feature of the power inflator on your bc. I tell you why that's the best way to dump air all the time; it is a one way valve, meaning, if you were to dump all the air and continue pulling the hose as if to dump more, no water would enter your bc. On the other hand, by dumping air out of your manual inflator button, once all the air is out of your bc, water gets in, which not only ruins the inside of your bladder, it can cause you to be more negatively buoyant. One more benefit of the pull-to-dump, if you're in a heads up attitude, the dump is always the highest point, so no risk in not dumping air due to holding a power inflator too low, especially if the velcro that secures the power inflator to your bc is low on the shoulder pad.
Here is something that, at least for me, has been of great help in determining weight:
http://dive.scubadiving.com/html/200105buoyancycalc_chart.html
One last point; don't beat yourself up. You seem to be a perfectionist, which is good (I am too), but don't forget the most important law of learning, the law of practice and drill, which states that "things most often repeated are best remembered." (from the flight instructor's fundamentals of instructing handbook)
Learn from your experience and do your best to be aware it can happen at any time so stay ahead of the ascent and anticipate it. And by all means, Dive Dive Dive!!!
Semper safe
Rick
OP
appleofthesea
Guest
Scubaguy62:
Hi Scubaguy62,
Thanks for your reply and suggestions. I am glad that you were ok after your experiences too.
I am of average build, more on the thin side than thick side. I use a custom made wetsuit -- it is a 7mm full suit and a 5 mm shorty on top. My hood is 5 mm. I know that the initial 30 lbs of weight was too much -- but I wonder if the 24 - 26 lb range is the limit for how much weight I can take off of my belt. Do you think it is still too much weight considering my thick wetsuit?
appleofthesea:
Check out the chart I posted earlier. The average wetsuit has 2 - 3 lbs of buoyancy for each mil of thickness. You're diving with, if I understand you correctly, a 7 mil full suit and a 5 mil shorty on top, right? that's 12 mils on your torso and upper extremities. One question, if I understood you correctly, how can you move in 12 mils of neoperene? I guess you're not using enough weight, since using the minimum of 2 lbs per mil you'd need 24 lbs just to compensate for the buoyancy of the suit. To that you'd need to add the weight you need for your body, gear, and to compensate for variances in your tank's buoyancy. Honestly, if you don't have a problem with mobility, go ahead, but if I were you, I'd consider diving dry.
Rick
OP
appleofthesea
Guest
I do not have a problem in mobility in the 2-piece wetsuit. Since it is custom made it is very fitting and does not appear very bulky.
The full suit is really 6.5 mm. The shorty is 5, but it does not have sleeves. The only functional difference between this an a farmer john/jacket is that the top piece on mine has shorts attached to it. It is less bulky that the 7mm farmer john/jacket style suit. It keeps me warm (sometimes almost too warm when I am above the thermocline on a hot summer day).
I think that 24 lbs is the minimum I can use, and it is a little difficult with 24. From what you are saying, 26lbs seems appropriate.
Maybe one day I'll go dry. I got a good deal on a custom suit though so I jumped on it -- a lot cheaper than a dry suit. In the summer sometimes I just wear the shorty with a rash guard shirt underneath so it is pretty versatile.
Thanks for your response.
The full suit is really 6.5 mm. The shorty is 5, but it does not have sleeves. The only functional difference between this an a farmer john/jacket is that the top piece on mine has shorts attached to it. It is less bulky that the 7mm farmer john/jacket style suit. It keeps me warm (sometimes almost too warm when I am above the thermocline on a hot summer day).
I think that 24 lbs is the minimum I can use, and it is a little difficult with 24. From what you are saying, 26lbs seems appropriate.
Maybe one day I'll go dry. I got a good deal on a custom suit though so I jumped on it -- a lot cheaper than a dry suit. In the summer sometimes I just wear the shorty with a rash guard shirt underneath so it is pretty versatile.
Thanks for your response.
Hey Apple is Scubaguy right your diving in 12 mil on your torso? He's got a great idea try diving dry. But if it's a custom suit I'm sure you paid a pretty penny for it. So it may be hard to switch now. If you can , check into a drysuit rental, but be sure to get instruction on drysuit diving. Once you dive dry you'll have a hard time crawling into a wetsuit ever again.Dive Safe, Dive Alot-M
cdennyb
Contributor
In addition to many of the senior members excellent analysis comments (which I agree with completely)...I too had a lift vs sink issue back in the day I started diving (around 1973-74) and my OWI had us maintain a negative attitude when we started our accent. (I understand yours was uncontrolled but this is just something for you to think about) The thinking was that we: 1- wouldn't get out of control as quickly on our trip to the surface.appleofthesea:
2- we would be in control of our accent because we had to fin toward the surface. (If we stopped finning we'd sink a little)
3- It allowed us to get a better 'feel' of our buoyancy and develop the skills necessary to get good at it.
4- We didn't have computers so we had to estimate our accent rate from depth gauges and watches. (Primitative huh?)
Anyway, after 26 years of diving, I still find myself occassionally in a situation where I think I'm coming up a bit too fast and scramble to dump air and get back in control. Remember, underwater, everything should go at a slow pace. Even if you're out of control! LOL
dennis
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