GreyhoundsAreFast
Contributor
My AOW instructor went head first all the time. I do it now too but I could see it being a problem for divers that have trouble equalizing, especially because feet up means you can kick your way to the bottom.
Duck dive descent?
- Thread starter northernone
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I've done duck-dives after a back roll or giant stride into the water, but never as a head-first dive off the boat. My only concern is someone could use a duck-dive to cheat a bit on their weighting, and end up under-weighted on the way back up and unable to easily hold a SS.
drk5036
Contributor
I've thought about this as well, So basically I've tried to dive down to about 4 meters or so, then flatten out the rest of the way down. If I was significantly underweighted by some accident, it would be hard to maintain my depth and I would know something is wrong and head to the surface. If I was OK at that point, I figure at the end of the dive at most I'm going to be 1 kg or so underweight, which I should be able to compensate for with wetsuit compression and slightly shallower inhales. Worst case, you dive deeper and grab a rock or something. But in general I think you would quickly be able to determine if you had a serious problem with your weighting.
JamesBon92007
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I'm apparently more buoyant than I look like I ought to be--I'd tell them how much weight I need and they'd give me less because they were sure I'd be over-weighted so I'd end up doing my safety stop with empty lungs and at least one time, swimming around with a big rock. At least now I know they will probably try to under-weight me. I just have to quit trusting them and check how much they are giving me. Now I have to start all over again because I got a new SS backplate. They say it weighs 5.5 lbs however in fresh water it only weighs 4 pounds. People seem to forget that buoyancy is about displacement and stainless steel displaces more water than lead for any given amount of weight on dry land.
Eric Sedletzky
Contributor
I always start my descent with a duckdive. I have to because the way I’m weighted there is no other way for me to get down, even with a full tank. At the end of the dive I end up at 15’ perfectly weighted with no air in my wing, so that’s just how it works out.
Bob DBF
Contributor
Divers overlook the amount of trapped air in their rig, especially on the first dive, and how it effects your buoyancy. If one sets their weight after the dive at 15', the trapped air is gone and wetsuit rebound is accounted for and therefore your weighting will be less than the eye level at surface initial check. This will probably leave you slightly positive on the surface with a full tank, depending on size, necessitating a duck dive.
With a BC a kilo or two extra is no big deal, but without a BC it makes a difference. Of course freedivers, or divers that may have a long walk to the water, get pickey about weight even when they don't have to.
Bob
boat sju
Contributor
I've also been known to kick up hard on the surface while venting and exhaling. Then push myself down with my hands several feet before I roll forward to head down. That look must really bother the young ones.
The first time I dove in my semidry I had about 12 pounds in my belt and felt very heavy on the bottom (85'). The second dive that day I felt much lighter and more comfortable on the bottom, but needed to climb down the anchor line at the beginning of the dive for the first 15 feet. I was neutral at 15 feet on the safety stop, however. I thought this very curious, but the answer was staring at me from the deck. It was of course the weight belt I had completely forgotten to strap on. I was shocked by the difference the trapped air in one's rig can make. I still kind of am. I don't think that trapped air was a full 12 pounds, but it was (and continues to be) at least 7 or 8. Trapped air really isn't stressed enough in how to do proper weighting, at least in my own experience.
Eric Sedletzky
Contributor
I always say, if you want to teach someone about proper weighting just take away their BC.
At that point weighting becomes critical. It also becomes crystal clear as to how much less they actually need as opposed to how much they think they need or have been programed to believe they need.
After they “get it”, then give them back their BC and guaranteed they’ll realize they only really need to use it at the deepest part of their dive.
At that point weighting becomes critical. It also becomes crystal clear as to how much less they actually need as opposed to how much they think they need or have been programed to believe they need.
After they “get it”, then give them back their BC and guaranteed they’ll realize they only really need to use it at the deepest part of their dive.
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