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Jonah
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OK, not sure if this is really the right section for this question but I couldn't see anywhere better.

When I started learning to dive, I was taught to do ascents where the body position was pretty much vertical. We were told not to use the BCD as an elevator (i.e. inflating it to rise up), but to slowly fin upwards while dumping air when necessary to maintain neutral buoyancy. OK, I can see the logic in that, so that's how I did my ascents.

However, since joining YD I've been exposed to a lot of divers doing things in different ways. I've noticed that some people - who appear to know what they're doing - tend to do horizontal ascents. OK, I can see the logic in that; I can see why it might be better than a vertical ascent from a decompression perspective.

So, I've been trying that on my last few dives. I've had varying degrees of success depending on the conditions - my current style could probably be described as a 'diagonal ascent'
  It seems much easier when ascending on a line than doing a free ascent. The main problem I've got is that I don't actually know what I should be doing in order to ascend horizontally.

So my question is: what are the mechanics of horizontal ascents? Do you

(1) use your wing/bcd/suit to lift you, OR
(2) use your wing/bcd/suit to remain neutral, and ascend through breath control?

I suspect that (2) is the answer, and I've actually got it to work (once) in the swimming pool, but if I should actually be doing (1) then now would be a good time to find out!

Thanks for any advice,
Tom
 

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Just not enough dive time.
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I've done a couple recently Tom, not bragging as I find it not the easiest thing to do. But what I did was to get nice a neutral, no air in wing just in the suit and as I rose in the water column the autodump just set me right. I would say it was one of the best feelings I have EVER had in diving EVER. Keep practicising mate and enjoy.


Matt
 

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Grumbler-chief in Residence
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Tom,

For what it is worth, it is easier to stay flat with a wing than a BCD, for me, the moment just arrived as soon as I started to do deco. It is just more comfortable, so flat is how you stay.

Andrew
 

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i mostly do my ascents horizontal as i find it easier to keep my position in the water  
as for ascending itself i use my breath to bring me up slowly releasing a little air out of my drysuit cuff dump just to keep me stable and it works fine for me and thats with a normal bcd and a pony not any kind of wing  as for the pic its of me coming up from 22 metres at stoney onto the shelf at 7 metres reeling an smb thats my normal ascent position
 

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"Three sheds"
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I'm new to horizontal ascents, and am by no means perfect at them. I've found that I need to get my trim pretty much dead on at the bottom. If you're weighting's wrong (ie if you stop motionless you rotate) then horizontal ascents are very much harder and I can only really do them while swimming or drifting.

Laters,
   Janos
 

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I pretty much do as Matt does,

By the time I get to the end of the dive and have got to 10m ish,  I dump any air in my wing and use the suit to maintain neutral bouyancy.

I can then control the ascent and a stop at 6m just using breathing control.  The big advantage with using the suit for neutral bouyancy at this stage is I do not have to worry about dumping air from any source.
The suit automatically vents.

Daz
 

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Unless of course like me you have a cuff dump...
 

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[b said:
Quote[/b] (Noel Johnson @ Mar. 21 2004,21:56)]Unless of course like me you have a cuff dump...
Ludite  


BTW Tom,  Have you got the Sitec valve yet.

Daz
 

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<font color='#000080'>Daz,

I have to rock onto my right side to dump as I ascend, rising in a horizontal position. If I was to rely on my dump doing its own thing by its self I'd polaris to the surface. I'm interested to kow how your suit boyancy does not lift you out of control if your in a horizontal position as your dump will be level with your torso and not above. I'm I wrong here, in that you are slightly at an angle, feet lower than head?

Dave C
 

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[b said:
Quote[/b] (MATTBIN @ Mar. 21 2004,20:23)]I would say it was one of the best feelings I have EVER had in diving EVER.
No contest.

Mine was when I shagged the wife in the Ionian Sea!


Sorry.  
 

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[b said:
Quote[/b] (dcrampt @ Mar. 21 2004,22:17)]Daz,

I have to rock onto my right side to dump as I ascend, rising in a horizontal position. If I was to rely on my dump doing its own thing by its self I'd polaris to the surface. I'm interested to kow how your suit boyancy does not lift you out of control if your in a horizontal position as your dump will be level with your torso and not above. I'm I wrong here, in that you are slightly at an angle, feet lower than head?

Dave C
I used to have to go slightly head high with my old suit (Had a Apeks autodump fitted).

My new one has a Sitec and I have found out that if I lift my left elbow so my hand is at my waist it dumps a treat.  So my elbow is actually the highest point and because of where the autodump it sited it is just slightly above my back.  Before I discovered this I also used to rock slightly so the whole of my left side was high.

Daz
 

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DUE CEO, Booking agent, Coffee maker & Dogsbody...
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Tom

The fin strokes should just be a couple to get you started. If you are correctly buoyant then you can continue up dumping or letting your suit dump as you go (dont try letting your suit do the dumping if you are in a semi-dry
)

When you get control really good you should be able to do that on your lungs to get you started, but get lots of experience first, doing to much on your lungs in poor vis and with no reference point can potentially be very damaging, i.e. Inhale to assend in poor vis not realising you have started and then stretching or bursting a lung.

You really need a datum line to use when first practicing this.

Dive Safe

Paul
 

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I use breath control primarily to do a horizontal ascent but also help a little with my fins kicking downward.  I really can't describe how I do it, I found it by accident.  When I was practicing backward finning I found that if I did it a certain way, I'd rise.
 

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I also heard something about horizontal ascents were good for decompression but when doing the TDI advanced nitrox/deco procedures we were taught to ascend vertically at the fastest possible safe rate.
Is it possible to ascend horizontally at this sort of speed while maintaining full control of the ascent?  Does it matter much about the ascent if your stop is horizontal?
I have no idea.
 

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<font color='#0000FF'>Dont know about the TDI procedures but horizontal ascents are going to discourage all the bubbles from going to the brain - or so goes the rationale.
I use them personally, just got a new suit and have found them a bit tricky - auto dump instead of cuff - so thanks Daz, I'm gonna nick your method  


The only thing I'd add is that I will invert slightly at the start of the ascent to put a bit of air (not a lot!) in me boots, I find splitting the bouyancy this way makes lying horizontlly an effortless task.

Aside from anything else, HA's look cool!  


Stu.
 

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That is a very good point.  Since dive rule no.1 is 'Always look good', this may be a very useful technique.  
 

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[b said:
Quote[/b] (PressurE @ Mar. 22 2004,09:37)]Dont know about the TDI procedures but horizontal ascents are going to discourage all the bubbles from going to the brain - or so goes the rationale.
I use them personally, just got a new suit and have found them a bit tricky - auto dump instead of cuff - so thanks Daz, I'm gonna nick your method  


The only thing I'd add is that I will invert slightly at the start of the ascent to put a bit of air (not a lot!) in me boots, I find splitting the bouyancy this way makes lying horizontlly an effortless task.

Aside from anything else, HA's look cool!  


Stu.
Forgot to mention,  my feet are slightly high,  I think it is termed the parachute pose.


Daz
 

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Jonah
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Discussion Starter #19
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Thanks guys - lots to think about there. Looks my next few dives are going to be in a wetsuit (holidays coming up), so I'll experiment then see how it converts to a drysuit when I get home.

John's account of TDI teaching vertical ascents is interesting - I wonder what the pros and cons of horizontal and vertical actually are? I also thought that *slower* ascents were safest (though I'm thinking about no-stop recreational dives, may be different for deco stuff?).

Daz - yep, I've got the sitech valve fitted (for the benefit of everyone else, I was having problems with an apeks high-profile autodump that seemed to be in the wrong place on my suit and wasn't working well). It does seem a bit better, I've had fewer problems with it. However, I've only had about half a dozen dives since fitting it, so I'm still keeping an eye on it.

Tom
 
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