Review Diving the Avelo System

[EdMcNeill09]

@EdMcNeill09 I'm not familiar with the Hydros, but golly, a 13 lb bcd that needs an additional 14 lbs of lead? That's ridiculous. What have they got in there, block styrofoam? To be clear, I'm not saying you're wrong, I'm just shocked at a BCD that floaty. My Cressi Aquawing (a BP/W with removable padding) weighs ~7 lbs, and with a full AL 80 is negatively buoyant even with the padding. I usually dive it with 4 lbs in still water to account for air loss, maybe 6-8 if I'm wearing a 3mm suit. So, yeah, a 13 lb hydros that requires an extra 14 lbs of lead must be floaty as balls.

Sidebar for comparison: my BCD weighs 7 lbs, I'd probably dive 4 lbs of lead in a shorty, 6 in a 3mm, so 13 lbs there. If my goal was to go ultralight, I'd dive a steel 72, which when I weighed mine came in at 32 lbs full (And at ~2400 PSI, have roughly the same gas as Avelo when you leave room for water, as I understand it). With an AL 80, it's more like 35-40 lbs, so weighs in at somewhere between 45 and 55 lbs I'd say. All that, and I can travel with it just by putting it in the carry on and renting tanks.

Now, that being said, I feel like the real selling point of avelo is the easy buoyancy, which I have no frame of reference for, as I've never tried it. Seems like a cool idea, though tbh my breathing is where most of my buoyancy related struggles come in, but at some point I would not mind giving Avelo a try.

The hydros is +2lbs buoyant. Most jacket styles are +1 or +2 lbs buoyant regardless of their weight. A BPW by contrast is typically-2 to -8 lbs buoyant depending on materials. But since most divers dive jackets I went with the hydros since I have 7 of them and know it pretty well. Rarely dive the things but I know them and people love them.

When I fill. As I hope to soon, my Avelo tank to 300 bar I will have almost as much gas as a steel hp 100. But with much better buoyancy.

I currently fill to around 3500 psi so closer to a n al80 which weighs 40lbs filled and 34 completely empty. Give or take a few ounces.

So basically Avelo is substantially lighter. We can argue about how much lighter with different fills etc, but I think I basically agree with you that weight is not the real point. It’s definitely nice to have lighter gear but the biggest deal is the incredible large zone of stable buoyancy.

I recently certified a couple of scientific divers who are also professional underwater photographers. They love it and feel it’s an incredible platform for underwater photography and scientific diving. Managing buoyancy is a task in both these disciplines and removing the need allows a greater focus on the tasks at hand.

 

[EdMcNeill09]

. The amount of weight seemed correct as I easily achieved neutral buoyancy with a single pump. Unfortunately, all the weight in my tank boot made me somewhat tail heavy and interfered with my trim.

yes. The new tank has much better trim characteristics. The first generation tank had heavier top of the tank components. Stainless steel, brass. The new tank is no longer top heavy. Consequently putting all the weight in the cage will make you bottom heavy.

I’m hoping the Shearwater jetpack will have trim pockets. Otherwise I’ll probably add trim pockets to the tank strap.

The change in materials was made as a general improvement in a second generation tank. The change not only improves trim it also makes maintenance easier.

 

[inquis]

When I fill. As I hope to soon, my Avelo tank to 300 bar I will have almost as much gas as a steel hp 100.

I'm afraid not, because of real gas effects. Allowing for 1L of water to cancel the +2lb initial buoyancy, at 300 bar you will have 84.8 cuft (10% more than an AL80 at 3000 psi/207 bar). The HP100 diver will have 18% more than you at rated pressure.

 

[SouthernSharktoothDiver]

@EdMcNeill09 And that is an entirely reasonable point. The jacket style would, of course, be the comparison for "standard scuba" and while we could indeed go back and forth quibbling over ounces, at the end of the day, that does not appear to be the selling point of this system.

Side note, but on the weight of an AL 80, my catalinas seem significantly lighter than my Luxfers, to the point that I've repeatedly stopped to check that a Catalina is full because it feels so light it must be empty, but they're always full. Is a Catalina lighter than a luxfer, or is it all in my head?

 

[EdMcNeill09]

I'm afraid not, because of real gas effects. Allowing for 1L of water to cancel the +2lb initial buoyancy, at 300 bar you will have 84.8 cuft (10% more than an AL80 at 3000 psi/207 bar). The HP100 diver will have 18% more than you at rated pressure.

When diving a tank filled to 300 bar you weight yourself to be neutral. You do not run the pump. Obviously this is not something we do in training but is entirely manageable for an experienced diver. The trick is finding a shop who will give you a 300 bar fill.