Vertical vs horizontal ascent/descents

[RJP]

"The best method is the one that works best for you..."

I had a friend who's grandmother used to get rear-ended all the time when she was driving. We assumed she was just unlucky, until we found out that she had "a better method" for use of her turn signal. She would put the left blinker on to indicate "Pass me on the left, I'm turning right."

Sort of puts the old "whatever works for you is best" chestnut in a different light, huh?

 

[Charlie99]

newb diver here so i've never done a wall dive; i've been doing my descents w/my head up (i thought padi said that's the safest way to descend viz a viz equalization). should i change my descent do horizontal/head slightly down?

You may find equalization easier during the first 20' if you do it vertically. If you need to do that, then do it. After that you would probably find convenient and easy to go horizontal during the dive, including the portions where you are swimming along while gradually descending and ascending.

Sometimes, such as when going up and down a mooring line on a wreck, the ascent and descent are a very clearcut, separate phases of the dive. Either horizontal or vertical orientation will work for that, although staying horizontal makes control of ascent/descent rate easier since you have more drag in the vertical direction.

On a wall dive though, you often first descend 15 or 20' to get off the surface, then swim along the wall checking stuff out as you descend gradually towards your max depth. The ascent from a wall dive is often done very gradually, in several phases, such as 100' up to 70' then up to 50' then up to 30' --- taking several minutes at each depth and several minutes between depths. Obviously, the whole thing works much easier if you can control your buoyancy such that you gradually rise or fall while swimming along horizontally.

Another way to look at this vertical vs. horizontal ascent thing is to imagine doing a shore dive where you descend onto a 6' bottom, then follow a gradual slope out to your max depth and then back up. Pretty clearly, doing a gradual descent and ascent while completely horizontal makes a lot of sense for that type of dive.

The next time you do a safety stop, try to adjust your buoyancy so that you maintain depth without finning. Try that vertically and horizontally and you'll see that it is easier when horizontal.

 

[captain]

I agree except I use my lungs to ascend/descend rather than my fins.

I use my lungs to maintain my trim at the desired depth.

 

[Blackwood]

I don't quite understand the advantage of horizontal ascent. I do see the advantage of horizontal descent and tend to do it. Question for you horizontal-only folks: How do you ascend/descend an anchorline horizontally?

I do it the same way I ascend or descent without a line. I'm confused. What do you mean by how?

Unless you are actually pulling yourself up the line, it shouldn't make a difference.

I use my lungs to maintain my trim at the desired depth.

My trim is a function of how my gear is set up. Full lungs or empty lungs I'm trimmed the same. I control my depth with my lungs (large inhale/exhale for large depth changes, normal breath to stay in place), and use my BC to compensate for loss of buoyancy with depth.

 

[Blackwood]

Back to the original question of the post....

There are a couple of reasons that PADI suggests an upright descent...

2. Maintaining direction/heading. Along with item one, I find that many newer divers tend to cork-screw when descending head first in lower visibility situations.

That is a major reason I prefer horizontal trim. If vertical in a heavy current, it's very difficult to stay where I want to stay since my fins are facing the wrong way. Horizontal, a kick here or there keeps me in position.

 

[Boxcar Overkill]

Pontificate the benefits of proper trim all day, nobody is arguing this.

You may not be arguing it anymore, but you were arguing it. You were claiming that, not only was it unnecessary to keep trim if you wear a jacket, you actually claimed it was counterproductive. I, as well as others, disagree.

Now it looks like you're conceding that argument? That's fine, if that's the case. If you no longer maintain that it's counterproductive to try to maintain trim in a jacket BCD, then that point is cleared up.

 

[captain]

I do it the same way I ascend or descent without a line. I'm confused. What do you mean by how?

Unless you are actually pulling yourself up the line, it shouldn't make a difference.



My trim is a function of how my gear is set up. Full lungs or empty lungs I'm trimmed the same. I control my depth with my lungs (large inhale/exhale for large depth changes, normal breath to stay in place), and use my BC to compensate for loss of buoyancy with depth.

When I refer to trim I mean maintaining neutral bouyancy not body position. I could maintain a horizontal position going up or down but I prefer finning to do that rather than ajusting bouyancy with the BC to do it. I ajust bouyancy once I arrive at my chosen depth but I am horizonal when I swim in a horizontal direction, I am head up going up and head down going down.

 

[Boxcar Overkill]

In my case, I don't descend very quickly on pure weight alone. So If I'm at the beginning of my dive I often kick a little to help me get down faster. I'm mainly horizontal, but it depends on how much of a hurry I'm in.

I suspect one reason new divers overweight themselves is because they believe they should be descending faster at the start of the dive, and since they are vertical they don't have their fins to help them get down. They assume they are underweighted, rather than accepting a slow descent or moving into a position where they can kick down.

 

[1_T_Submariner]

The only time I might ascend vertically is when there is Boat traffic or something that you need to look 360 degrees for. But usually during a 15' stop I roll over and look up so I know what is up there without becoming vertical.

 

[RJP]

I suspect one reason new divers overweight themselves is because they believe they should be descending faster at the start of the dive, and since they are vertical they don't have their fins to help them get down.

More often than not I see new divers finning UP while trying to go down.