Over-weighted or under-aired?

[jagfish]

DDT Vlog#18 - Too Much Weight?

For sure a topic that has been well-covered on the net...my take on why beginning divers often choose to be negatively buoyant...as a result of risk triage/aversion...the lesser of two weevils

There's lot of talk on the net about divers that are apparently too heavy and/or silting up the bottom. This video explores the issue and that of comfort with BC air control:


1. Is that diver overweighted or "under-aired"?
2. New diver mindset regarding being too heavy or too light during a dive
a. Danger of too "heavy"
b. Danger of too "light"
3. Lack of confidence is dumping air from BC
4. How to gain confidence in dumping air...practice!
5. Achieve correct weighting
6. The right amount of air in BC
7. Also use lungs for buoyancy control
8. How to practice venting BC
a. Vertical vent
b. Horizontal vent
9. Know your BC/rental BC
10. Finning
a. Finning for propulsion
b. Finning for buoyancy
11. Tip: Frequent finning pauses to check buoyancy

Safe diving!

Jim

 

[Colliam7]

Good video. I was a bit concerned by the title ('under-aired' ?) before I watched it, but Jim brings up several very useful points that sometimes do not get much attention in OW training - using the butt dump, and interrupting finning periodically to check buoyancy. Worth a look, particularly for newer divers but for others as well..

 

[jagfish]

Good video. I was a bit concerned by the title ('under-aired' ?) before I watched it, but Jim brings up several very useful points that sometimes do not get much attention in OW training - using the butt dump, and interrupting finning periodically to check buoyancy. Worth a look, particularly for newer divers but for others as well..

Many thanks!

 

[ls1dreams]

Nice video. I had a lot of weighting issues on a previous dive trip, even with being VERY well aware of my dump valves.

4.5kg = tough to initially descend, great for the bottom, a real struggle at < 10m near the end of my dive to stay down.
6kg = sank like a rock, needed a good amount of air in the bcd on the bottom, perfectly fine at end of dive.

This was in a 5mm wetsuit though, which I imagine makes things a lot more difficult.

 

[archer1960]

Nice video. I had a lot of weighting issues on a previous dive trip, even with being VERY well aware of my dump valves.

4.5kg = tough to initially descend, great for the bottom, a real struggle at < 10m near the end of my dive to stay down.
6kg = sank like a rock, needed a good amount of air in the bcd on the bottom, perfectly fine at end of dive.

This was in a 5mm wetsuit though, which I imagine makes things a lot more difficult.

Did you try 5 or 5.5 kg? I normally vary my weights by 1 lb (.5 kg) at a time until I get them right.

Wait until you need a 7mm suit and a hood! When I started using my full cold water gear setup, I found I needed 20 lb (a little over 9kg, I think). And a fair amount of air in the BC early in the dive when at depth. But it's perfect at the end when I check it at 6 ft. Most of my diving is from shore, and we typically swim in until we can almost stand up, so I generally check my buoyancy at 6' rather than 15'. There usually isn't a safety stop, because the gradual swim in along the bottom takes care of that.

 

[Bob DBF]

Good video. It gives insights to help solve the problem. Without addressing buoyancy control, proper weighting is more of a hit or miss procedure.

Under-aired is an especially apt term here, where the 7mm wetsuit looses a lot of buoyancy at depth, even if you are initially properly weighted.


Bob

 

[Resqdivemedic]

Great video. Thanks for the tips.