Review Diving the Avelo System

[SouthernSharktoothDiver]

@scubadada @lowwall These explanations make sense. I thought a while ago that Avelo might be better off using a second tank for buoyancy management, so that your airfills are not tied into your buoyancy system. I did a little research, and found I invented the Dacor Nautilus. Sigh. Someone always steals all my good ideas...decades before I have them.

Presumably the technology does not currently allow for a system with larger air capacity without losing either streamlining or the light weight that is the major advantage Avelo lays claim to, but as always, technology progresses. Assuming Avelo gains a strong enough following to warrant a 2.0 version in a decade or two, it will be interesting to see what new advances in materials science, manufacturing, and pump/battery design might allow. Still, for the moment at least, it does look like there's a definite upper bound on how much air avelo can carry without becoming heavier and bulkier than a standard setup.

I did have one question: if someone were to dive Avelo with a sidemounted AL 80, would the system be able to adjust for that? The AL 80 would presumably change your buoyancy by about 5 pounds over the course of the dive, as well as the several pounds of change due to the air in the hydrotank, for perhaps 8-10 pounds of buoyancy shift. As I understand it, Avelo typically can only adjust for around 4-6 pounds of buoyancy, but I thought perhaps if you breathed down the hydrotank first, you might could take on additional mass as the air volume in the tank is now lower. However, I feel like at a certain point you might run into safety concerns, or the inevitable issue of only have so much space to pump water into.

Thoughts?

 

[scubadada]

I have not dived Avelo off a boat. I have seen Avelo off a boat and assume the tanks fit into normal tank slots

 

[Trailboss123]

I have not dived Avelo off a boat. I have seen Avelo off a boat and assume the tanks fit into normal tank slots

Did you ever in your wildest dreams think that your Avelo post would generate 66 pages of Scubaboard content? Totally amazing

 

[inquis]

I did have one question: if someone were to dive Avelo with a sidemounted AL 80, would the system be able to adjust for that?

Short answer: probably, but I suspect for reasons other than what you're thinking based on your post.

Details:
At the beginning of the dive you would want to be positively buoyant by +2 lb. Assume this is possible. If you consumed all the gas in the Avelo tank, there would be room for an additional 9 L of water or 20 lb of ballast (ignoring the space the bladder takes up for simplicity). That's the equivalent of about 250 cuft of gas you could conceivably take with you and consume while still remaining neutral.

The difficulty lies with that initial assumption. For the normal Avelo system, the "fixed parts" (cylinder/plate/pump/batteries/lead/diver) have some buoyancy (call it X1), and we know the total buoyancy will be +2 lb. Since X1 - 6 lb (Avelo gas weight) = +2 lb, we see that X1 = +8 lb. If you add an AL80/reg, the fixed buoyancy will increase by +2 lb (assuming +4 lb empty tank in salt water - 2 lb reg), so X2 = +10 lb. The total buoyancy will then be: B2 = +10 lb (X2) - 6 lb (Avelo gas weight) - 6 lb (AL80 gas weight) = -2 lb.

That's a problem, but possibly not insurmountable. If you had added lead to the system, you could just remove 4 lb of lead, and you're back to your target +2 lb starting buoyancy. Enjoy the additional bottom time and watch that NDL.

If you didn't add lead (e.g., you are diving without a wetsuit), what do you do? Avelo already solved this issue by making "buoyancy pads" (I believe out of plastic) that can be attached to the system to increase its buoyancy. (Search upthread, and you'll run across mention of them.) The crucial question is whether those pads can add 4 additional pounds of buoyancy. You're looking at a volume increase of at least the size of a 2L soda bottle (not even counting the weight of the plastic). I have no idea how much buoyancy those pads add or how many attachment points are built-in.

Another option might be to use a more buoyant tank. Connecting the dots, you may guess this is why Avelo chose the carbon-wrapped cylinder in the first place. It wasn't just for the "cool factor".

Bottom line: I believe a side-mounted AL80 would work with Avelo in most cases. Weighting will be CRITICAL to safety and successful usage, but that's already the case for the normal system.

 

[SouthernSharktoothDiver]

@inquis As a buddy of mine is fond of saying, it's quite possible the juice isn't worth the squeeze. That's a lot of changes to make compared to just diving traditional doubles and using Avelo strictly for what it's been made for: single tank rec diving.

That being said, if it's possible to kludge together a working Avelo sidemount system, it shouldn't be too hard for the company to design a far more streamlined, user friendly equivalent, if they ever wanted to. Room for growth, as the business majors say.

 

[lowwall]

I have not dived Avelo off a boat. I have seen Avelo off a boat and assume the tanks fit into normal tank slots

I wasn't suggesting it didn't fit. But I think they may be 8" diameter tanks like an AL100, HP117 or HP133 rather than the 7.25" like an AL80, HP100 or HP120.

Most boats can accommodate the 8" tanks. But going larger would be a problem.

BTW, Avelo's refusal to provide the actual weights and dimensions of its products can only lead to the conclusion that they have something to hide.

 

[SouthernSharktoothDiver]

BTW, Avelo's refusal to provide the actual weights and dimensions of its products can only lead to the conclusion that they have something to hide.

I see three possible conclusions:

1. It's a corporate oversight. I can see a reasonable, if somewhat far-fetched explanation of some overzealous corporate stooge deciding this is important information that must be kept secret to avoid competitors ripping their product or something, or just straight up not realizing this is information divers would want/need. The big issue with this is, going by the video that was posted here, the founder is a diver, and would know that weight and buoyancy (and therefore volume) is a huge selling point to divers. Perhaps he's handing the marketing/information management off to a subordinate who's never been diving before though.

2. Perhaps the exact weight/dimensions of the unit changes fairly frequently, as newer materials, better batteries, smaller motors, etc. are incorporated into the design. Thus, there's "no point" in publishing a weight estimate that would soon become out of date and misleading. Credence to this is that, if you look at the Avelo total product weight from early in this thread vs now, the overall weight estimation of Avelo went up five pounds. Perhaps they wish to avoid such changes as much as possible. The major issue with this is that the total system weight has changed only once to my knowledge, therefore implying that such changes are in fact, rather rare.

3. They have something to hide. Perhaps they want to make it difficult for people to make direct, one-to-one weight comparisons of their current rig to Avelo. If I knew, for example, the exact buoyancy of an Avelo system, I could compare it to my own system to determine the lead I could lose, and from there come up with an exact weight differential between them, which might be less favorable than Avelo indicates on their marketing material. Supporting evidence for this is the rather impressive 75 lb weight estimate they give the typical scuba diver on their site, and the fact that, as I've said several times before (and still not received a good explanation for) Avelo actually increased their estimate of the average diver's kit weight by 5 lbs when Avelo's system weight increased, so that the difference remained 30 lbs despite Avelo being five pounds heavier than it was before. Note that this motivation isn't simply "Avelo is lying about their product being lighter" and more "Avelo is providing a product that aims to reduce weight, and benefits from you not being able to do the math and say 'eh, five pounds isn't really worth the trouble.'"

Please note that I do consider any of these three motivations, a combination of all three, or some secret fourth motivation I haven't thought of to be entirely plausible. I still find the change in the average diver's weight from 70 to 75 lbs on their site to be extremely suspcious, and would love an explanation of that. Like, please people, I think this is a cool product. I'd love to see what they'll make of it in five or ten years. If the price point ever comes down enough, I might even buy one. But the math kinda ain't mathing on some of these claims.

And like, seriously. On a diver charter in Ha'waii, I dove a rental jacket style bcd with standard AL 80 and normal regulator. All were scubapro brand gear. The 80 weighed 35 lbs, as is standard. I don't remember the exact BCD, but it was a decently high end scubapro, not one of those mass market "shop only" BCDs some companies allegedly make, and the heaviest scubapro jacket style BCD I found on their site was 10 lbs. I had 10 lbs of lead. The reg probably weight 2 lbs at the most. So, overall weight: 57 lbs, on the high estimate. This is 12 lbs above avelo, at the very most, and not the 30 lbs their site advertises.

Now, this is a decent amount of weight to save, and almost all of the savings are in lead I can now ditch, which is wonderful because adding something heavy to my kit which already weighs too much has always been frustrating...but why can't they just say 12 lbs of weight saved? Or give a range of 6-18 lbs or 12-20 lbs or whatever. Saying you save thirty pounds feels extremely cherry picked at the best, and at worst, does make me question the validity of their product overall. I don't know of any diver that's not using an unnecessary amount of lead with a 75 lbs single tank warm water rig.

Let me reiterate. I like the product. I'd happily try it, if doing so did not require traveling far, far away from where I live and spending several hundred dollars I don't currently have to spare. I would love an explanation of why the weight numbers don't add up. I'm just pointing out issues here people.

 

[scubadada]

Did you ever in your wildest dreams think that your Avelo post would generate 66 pages of Scubaboard content? Totally amazing

No, I would never have predicted the participation in this thread, nearly 66,000 views and over 650 replies. When I started the thread at the beginning of 2024, I simply thought divers on SB might appreciate hearing about new technology that they may not have heard about, let alone try.

I have given my short summary of the Avelo System before:
Neutral buoyancy is easy to achieve and maintain
The gear weighs about 15 lbs. less than my traditional warm water equipment
My gas consumption, which is already good, is the same with Avelo
I find it fun to dive

At the end of my initial post, I wrote, "Is Avelo the diving of the future, I don’t know? Expansion of the number of training sites, wider availability of equipment, sale of equipment to individuals, and presence of the Avelo Mode on a number of popular computer platforms are some of the variables." There are now Avelo Dive Centers in 5 US states and 3 other countries. Avelo equipment is for sale to individuals. The Avelo Mode is available on the Shearwater Teric, Peregrine TX, Perdix 2, and Tern TX in addition to the Scubapro G2 console.

I still do not have a good idea of how this topic will ultimately end up. My wife and I are going back to Bonaire in May. I will again rent Avelo gear for a few days and will report my experience in this thread.