Uncontrolled descent

[kazinvan]

Correct me if I'm wrong, but is the real reason for deaths related to uncontrolled descent really panic? What I mean is that even if I jumped into the water with way too much weight and had an equipment problem where both my drysuit and my BCD could not inflate then I would obviously start sinking quite quickly. At that point, I would ditch my weight and swim to the surface before I got too deep. If I get tangled in mono and I'm somehow wrapped up like a sausage and can't do anything then I hope my buddy comes to my rescue.

In most of these cases, does panic set in and divers just try to fix the problems as they rocket down to the botom instead of aborting and just coming up to the surface?

 

[miketsp]

hmm... in my lessons, I was told to go down with my body vertical, release all the air, and finning upwards to control the descend. then at the bottom, slowly add air to my bcd until i m neutral.

That is not good technique.
It's similar to the way that some agencies used to teach you to completely dump your BC before starting an ascent and then fin up and only inflate at the surface.
It was then proven that too many divers hold their breath automatically when they have to exert themselves.
As far as I know all agencies now teach neutral controlled ascents using buoyancy control.
I think the same reaction might kick in - and if you had to fin hard to control your descent you might automatically hold your breath.

The objective is good buoyancy control in all phases.

Edit PS - and of course if you're finning vertically near the bottom you are going to make yourself unpopular if you raise a cloud of silt.

 

[OE2X]

I have to agree with Mike here. I'll only add that the way my buddies and I descend is horizontally thus slowing and controlling our descent much like a skydiver.

 

[kazinvan]

I agree, horizontal descent/ascent. I think that is even more common for drysuit divers (like myself) because a vertical position will usually cause unwanted venting of air from the suit and also create a squeeze on your feet if in the head up position.

 

[Avic7]

The way I descend is that I start our vertical and end up being horizontal within 2 min or less during the descent. That being said, ignoring current, while going down and you are uncontrolled couldn't you use your fins to propel you upwards? Sure, you might be overweighted and your BC doesn't have enough air to compensate (at the time) but you still have your legs and fins (assuming you have not lost your fins) to slow your descent and maybe kick youself towards the surface?

 

[JaX NeMo]

After reading you guys' comments, I guess I will descend vertically but releasing just enough air to sink slowly. Then when nearing the bottom, get into horizontal position. The breathing part is quite subjective though, I breath normally and equalize a lot when going down.

Well, the reason we were told to release air when we are swimming to the surface is so that we maintain control, else the expanding air in the BCD will pull us up faster than we want and risk lung over expansion injuries.

But usually my dives, we go to the deepest and slowly swim to shallower area. That's the easier part. Hehehe!

 

[OE2X]

After reading you guys' comments, I guess I will descend vertically but releasing just enough air to sink slowly. Then when nearing the bottom, get into horizontal position. The breathing part is quite subjective though, I breath normally and equalize a lot when going down.

Well, the reason we were told to release air when we are swimming to the surface is so that we maintain control, else the expanding air in the BCD will pull us up faster than we want and risk lung over expansion injuries.

But usually my dives, we go to the deepest and slowly swim to shallower area. That's the easier part. Hehehe!

You will have a much more controlled descent if you are horizontal. If you are vertical feet first then when approaching the bottom you may silt up area as you move to horizontal.

 

[Avic7]

You will have a much more controlled descent if you are horizontal. If you are vertical feet first then when approaching the bottom you may silt up area as you move to horizontal.

The way I descend is that I start our vertical and end up being horizontal within 2 min or less during the descent. That being said, ignoring current, while going down and you are in a VERTICAL uncontrolled descent couldn't you use your fins to propel yourself upwards?

 

[MXGratefulDiver]

The way I descend is that I start our vertical and end up being horizontal within 2 min or less during the descent. That being said, ignoring current, while going down and you are in a VERTICAL uncontrolled descent couldn't you use your fins to propel yourself upwards?

Yes ... but it's poor technique. It would be much better to make the effort to learn how to control your descent properly than to develop inefficient habits to compensate for a lack of skills.

The reason most new divers descend vertically is because it's (a) what they're used to - as land-based, walking creatures ... and (b) what they're most commonly taught by instructors who don't want to make the effort to teach the skill properly.

The biggest problem with a vertical descent is that it leads to chronic overweighting ... due to the fact that when you're in a vertical position you WILL try to control your descent by finning. In effect, you're propelling yourself upward while your intent is to go downward. This leads to the mistaken impression that you don't have enough weight to sink, and so you add more weight that you don't really need. Overweighting leads to all kinds of buoyancy issues.

The most effective technique to descend is to deflate your BCD, exhaling to expel all the air from your lungs as you begin your descent. Once you are down a few feet, bend your knees to move your fins back. The force of the water pushing up on your fins will start to push your feet upward, naturally pushing you into a horizontal position. At that point, extend your legs as your body rotates into a horizontal position. Breathe normally, adding gentle puffs of air to your BCD to maintain a steady rate of descent. As you approach the bottom, inhale completely to stop your descent before your touch the bottom. When learning the technique, try to stop within three feet or so without touching anything. With practice, you can arrest your descent within inches of the bottom without ever needing to touch it. Then, as you exhale normally, add short puffs of air into your BCD to compensate for the air leaving your lungs ... just enough to remain in position.

This technique requires practice ... but once you learn it, you won't ever again have to worry about uncontrolled descents.

... Bob (Grateful Diver)

 

[Battery]

Yes ... but it's poor technique. It would be much better to make the effort to learn how to control your descent properly than to develop inefficient habits to compensate for a lack of skills.

The reason most new divers descend vertically is because it's (a) what they're used to - as land-based, walking creatures ... and (b) what they're most commonly taught by instructors who don't want to make the effort to teach the skill properly.

The biggest problem with a vertical descent is that it leads to chronic overweighting ... due to the fact that when you're in a vertical position you WILL try to control your descent by finning. In effect, you're propelling yourself upward while your intent is to go downward. This leads to the mistaken impression that you don't have enough weight to sink, and so you add more weight that you don't really need. Overweighting leads to all kinds of buoyancy issues.

The most effective technique to descend is to deflate your BCD, exhaling to expel all the air from your lungs as you begin your descent. Once you are down a few feet, bend your knees to move your fins back. The force of the water pushing up on your fins will start to push your feet upward, naturally pushing you into a horizontal position. At that point, extend your legs as your body rotates into a horizontal position. Breathe normally, adding gentle puffs of air to your BCD to maintain a steady rate of descent. As you approach the bottom, inhale completely to stop your descent before your touch the bottom. When learning the technique, try to stop within three feet or so without touching anything. With practice, you can arrest your descent within inches of the bottom without ever needing to touch it. Then, as you exhale normally, add short puffs of air into your BCD to compensate for the air leaving your lungs ... just enough to remain in position.

This technique requires practice ... but once you learn it, you won't ever again have to worry about uncontrolled descents.

... Bob (Grateful Diver)

Great post! It's post like these that help a lot. I currently am in the process of practicing that technique my past few dives. My goal is to never have to touch anything, to me its the closest thing to flying lol.

Superman Complex