Problems with descending. Trapped air? Nervous? Or underweighted?

[EireDiver606]

I recently bought a Halcyon Eclipse 30 with SS backplate. I used a steel 12 l (AL80?). I was very excited to use this and went for a quick solo dive around a pier in Donegal, Ireland. Max depth 3m.

There was lots of people there as there had been a lifeguard course on that week, and lots of people watched me, which I didn't like, especially as I've never used this equipment before. Little bit nervous.

This is with a 7mm + 5mm farmer john wetsuit.

So I jump in the water, try to descend but can't, this was with 4kg (10 lbs) lead + 3kg SS backplate(6lbs). Bear in mind I normally need about 8kg (18lbs?) to get down, so I thought I would need maybe a kg less as lots of buoyant fabric in the jacket is not there anymore.

I was trying to use as little lead as possible, is this correct?

I couldn't descend. I was trying to vent the wing as much as possible as I assumed I still had air trapped. I was upside down and using rear left OPRV valve, pulling as much as possible, this didn't work. When I came out, a friend told me that there was definitely air in the wing, so I went back in again with an extra 2kg because I couldn't vent it. Now I have 1 more kg than necessary, and I just barely got down, but was still fighting to stay down a little bit. I do not know if it was due to being a bit nervous with 100+ people watching me, or because I couldnt vent the wing, or because the tank or something was sitting on the wing or it was tightened too much that the wing couldn't expand so air was trapped.

Does anyone know how air gets trapped in the wing? How to fix it underwater? or if I was underweighted or both? Or nervous? Any advice is appreciated as this really REALLY p****d me off.

 

[Marie13]

Were you using an aluminum tank before or steel?

Don't try to use as little lead as possible. I ran into that once, ever again. Nervousness could be part of it.

I also have the Halcyon BP/W and since I need a lot of weight, I found the weighted STA insert (5lbs) to be very useful as it takes weight off my belt.

Did you reach behind you to feel the wing? Was there air in it?

 

[EireDiver606]

Were you using an aluminum tank before or steel?

Don't try to use as little lead as possible. I ran into that once, ever again. Nervousness could be part of it.

I also have the Halcyon BP/W and since I need a lot of weight, I found the weighted STA insert (5lbs) to be very useful as it takes weight off my belt.

Did you reach behind you to feel the wing? Was there air in it?

Actually now that I think about it, I used a steel 15 before. Sorry but not bothered to spend 80€ to get a weight insert of 5 lbs when I can 14€ and get a 2kg lead block.

When I surfaced, there was air in it. But underwater I knew there was air in it because I could vent a little bit, then it stopped working after a while but I still couldn't go down..... every now and then there was a few bubbles, but nothing really.

 

[Neilwood]

I am wondering (not knowing exactly where the location is of the rear dump valve on Halcyon wings) if when you went upside down, that the air was still trapped above the valve.

What I tend to do is roll very slightly to the side that the valve is on and push my bum up (only by a couple of inches) which ensures the valve is the highest bit ( note I am not doing big manoeuvres to achieve this).. That means that any air is in the vicinity of the valve and that it can easily leave the vent.

 

[2airishuman]

I feel your pain on this one.

Shallow dives with 7mm suits are difficult to get dialed in exactly right. I typically use more lead on dives like that than I would on a deeper dive.

It takes practice to get all the air out of a wing. Over time you develop an awareness of where the bubble is, and adjust your body position and choose which dump to use as needed.

 

[RyanT]

If I understand correctly, you were wearing a 7 mm AND a 5 mm farmer john AND an aluminum tank? If so, that is a lot of buoyancy. It's hard to say without being there, but with that much wetsuit and an AL tank, I'd guess you were a little underweighted.

 

[EireDiver606]

If I understand correctly, you were wearing a 7 mm AND a 5 mm farmer john AND an aluminum tank? If so, that is a lot of buoyancy. It's hard to say without being there, but with that much wetsuit and an AL tank, I'd guess you were a little underweighted.

Read my post. STEEL TANK

 

[RyanT]

I did read your post, it says steel 12 and then AL80?, so it wasn't clear to me which you were using.

I used a steel 12 l (AL80?)

 

[Russoft]

I have no idea how tall you are or your body composition. I'm 5'10", 170 lb, and wear a two-piece 7mm (probably compressed to the equivalent of 5mm) with a hood and gloves. With an AL80 I need about 18 lb (8kg) of lead to get under water. I think I dropped 2 lb / 1kg last time I dived but I also wasn't wearing a hood or gloves for that dive.

Your weighting seems about right to me based on my own numbers. Keep in mind it should be easy to sink with a full cylinder since your about 6 lb / 2.7 kg heavier at the beginning of the dive.

If you are indeed using a steel tank then it's not an AL80 (aluminum 80 cubic foot) and you're horribly overweighted.

 

[dmaziuk]

I haven't dived locally from certification and until this June, so there I was in a rental 7mm wetsuit desperately trying to get down. With about 20 pounds of lead on me, though with ALuminium tank and backplate. Squeezing the wing, finning in the air... Until my buddy told me to pull on the neck seal to let the air bubble out -- then I went down like a stone. And then I found out shallow muck is not at all like nice Caribbean reefs: you don't have plenty of time to slow down and level off, and the first time you see the bottom is when you planted your face foot deep in the silt. Oh, the embarrassment!

You may have to squeeze the last of the air out, depending on where the valves are. I wouldn't want to do it in 3m, though, because if I oriented myself so one of the valves is at the highest spot, some part of me would either be out of the water or planted on (in?) the bottom.