Proper ascent

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khacken

Contributor
Messages
423
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0
Location
Dallas, Tx
# of dives
200 - 499
What is the best way to make a nice slow controlled ascent. I just recently moved to a computer and found that I am ascending over the 30ft/s limit.

Here is my normal process:

Thumbs up to buddy and group.
Wait for response.
Go vertical.
Dump air.
Look at computer and start to fin up.
Stop suddenly one second later when the computer complains.
Start to sink.
Start to fin to ascend.
Stop suddenly one second later when the computer complains.
Repeat until I surface.

Here is what I am thinking I should do:

Thumbs up to buddy and group.
Wait for response.
Stay horizontal.
Rump slightly up.
Hand on rear dump valve.
Look at computer.
Go slightly positive by taking a deep breath of air.
Be sure to exhale a little as the ascent starts.
Dump air from rear dump valve as needed.
If rate gets too high, exhale more.
If rate still too high, dump more from bc.
If rate still too high, fin down.


This seems to have the advantage to fine tuning my ascent through buoyancy, and less physical effort.

The disadvantage seems to be that if your ascent rate get out of control or your dump does not work, you can end up with an uncontrolled ascent.

So what is best? Am I even close on the proper technique?
 
The most important step in making nice slow ascents (as well as a lot of other things in diving) is learning how to get really and truly neutral. Before working on ascents, learn how to just hang motionless in the water. Then doing an ascent per your proposed way is a simple, natural extension.

As a side benefit, you will find your air consumption goes down when you stay truly neutral and you don't have to fin to stay at the same depth.

If you have the right amount of air in your BCD, then you will slowly rise when you have full lungs, and descend when you exhale.

Just change your breathing pattern a bit to slowly rise up. Staying horizontal gives you more drag in the vertical direction and makes it easier.

Another trick to keeping ascent under control is to come to a complete halt every 10'. Go through a couple of breathing cycles while pretty much the same depth, and then go up another 10'.

-------------

I find that the ascent rate indicator of the computer is almost useless. It's much easier to look at tiny junk in the water to get feedback on your instantaneous rate of ascent.

Meanwhile, monitor time and depth on your computer to set the overall ascent rate.

To monitor and control the overall average ascent rate, an easy thing to do is to know what runtime should be showing on your computer when you reach certain depths. You also figure out as you start your ascent what the runtime should be when you surface. If you plan on doing any deep stops, just figure out the time you will finish them. Then if you do ascent to a deep stop a bit fast, you will spend more time at the deep stop, and thereby slow your ascent rate back down.
 
Well at least you are thinking about it so you are way ahead a lot of divers. Staying horizontal is a good start. It gives you more resistance to moving up and down since there is more area. Also check your weighting and trim. If you are diving with too much weight there will be more air that expands as you come back up. So staying close to neutral just makes the buoyancy control easier. The other thing to try is changing your trim. As you have already found out going head up tends to make you go up. And the reverse is true as well. You can change that dyamically by changing your foot and head position. Practice in shallow water until you get the hang of it. Good luck.
 
Kevin, just come dive with us more at the Swamp, you'll get the hang of it. I used to do the same thing, but diving with guys like Texass and Truckdiver have helped me slooooow down. Des made a comment the other day about them being the Quaalude Brothers, and I tend to agree, but it's great :D You're right on track with the thoughts about starting your ascent by inhaling, we'll just have to help you fine tune it. Everytime I ascend, after the safety stop, I make it a game to ascend 1foot, stop for a few seconds, ascend another foot, stop, and so on. I do all this strictly with breath control. It's helped me with bouyancy control as well as ascents.

Keep showing up, we're always glad to help any way we can...
 
Thanks for the help! Now the next question... Do you blow out a tiny stream of bubbles the whole ascent? Is just breathing normal after that first deeper breath ok? Reviewing my OW book, it states that breathing normal is ok on the ascent, but then they tell you to fin up, so I am guessing they expect your lungs to be mostly empty.
 
Firefyter:
Kevin, just come dive with us more at the Swamp, you'll get the hang of it. I used to do the same thing, but diving with guys like Texass and Truckdiver have helped me slooooow down. Des made a comment the other day about them being the Quaalude Brothers, and I tend to agree, but it's great :D You're right on track with the thoughts about starting your ascent by inhaling, we'll just have to help you fine tune it. Everytime I ascend, after the safety stop, I make it a game to ascend 1foot, stop for a few seconds, ascend another foot, stop, and so on. I do all this strictly with breath control. It's helped me with bouyancy control as well as ascents.

Keep showing up, we're always glad to help any way we can...

Thanks! Yeah, you are the one that really got me thinking about this. I was finning and you guys are just floating along. I was impressed with the skills I saw out there. I dove with Debra and Larry last week and I was surprised I didn't drive them nuts with all the beeping during the ascent.

I plan on being out there at CSSP again this weekend. Ascent and navigation will be the main skills I will be working on.

Looking forward to diving with you again!
 
khacken:
Thanks! Yeah, you are the one that really got me thinking about this. I was finning and you guys are just floating along. I was impressed with the skills I saw out there. I dove with Debra and Larry last week and I was surprised I didn't drive them nuts with all the beeping during the ascent.

I plan on being out there at CSSP again this weekend. Ascent and navigation will be the main skills I will be working on.

Looking forward to diving with you again!

Kevin,

What day will you be out there. I could use a little work on my ascent as well.

Craig
 
khacken:
Here is what I am thinking I should do:

Thumbs up to buddy and group.
Wait for response.
Stay horizontal.
Look at computer.
Go slightly positive by taking a deep breath of air.
Be sure to exhale a little as the ascent starts.
Dump air as needed.

So what is best? Am I even close on the proper technique?

That looks almost exaclty like what I do (see slight edit). The only thing I would add to that is to get face to face with your buddy and keep with your buddy (within reasons of safety of course). Most problems during a dive come either during the initial descent (do that horizontal as well) or during the ascent. Staying face to face with your buddy keeps you in close proximity to assist or be assisted. (Buddy seperation is usually a factor in dive accidents)

As you are first learning this, its usually a good idea to practice stopping along the way to keep control. Later, as you do deeper dives, you can add deep stops starting 1/2 the depth until you reach your safety stop. (IE, from 100', stop at 50' 25' 15')

I don't know why PADI still teaches the vertical method but I cannot see any advantage in it unless you have no control of your buoyancy. (then its fix your buoyancy control and do the ascent/descents horizontally)
 

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