Review Diving the Avelo System

[SouthernSharktoothDiver]

So I found a thread on here discussing the dacor nautilus back in 2009. As it was something of a precusor to the Avelo (Ie, both are constant buoyancy systems) that has been compared to Avelo several times in this thread, I thought I'd link it here: Dacor Nautilus

Anyone here who used a nautilus/was around when it was around, why didn't it work out? It seems like Avelo is probably much lighter/more streamline due to integrating the air supply/buoyancy tank, but the Nautilus appears to have had the advantage of requiring less of a paradigm shift (you can use your normal air tank, no DIN required, no special computer program for air calculations). My guess is it died on weight, as someone in the thread from '09 said it weighed as much as small fridge, but I'm curious, since I have personally thought Avelo would potentially have an easier time being adopted if it didn't integrate your air with your buoyancy as it does.

So somebody who knows more than me about both of these systems...thoughts?

 

[Eric Sedletzky]

I wonder how the carbon fiber tanks will fare with the kind of abuse that Al80s get in rental. Carbon getting banged around on rocks, pavement, fill stations and truck beds does not sound like a good idea.

The Catalina rental shop says they are spraying Rhino liner on their tanks to protect them but that will prevent a proper visual inspection -- that's one of the main reasons that vinyl-coated steel tanks fell out of favor.

spraying Rhino Liner on aluminum tanks sounds like about the worst thing they could do.
They should just strip the tanks down to bare aluminum and let them breathe, who cares how they look? They would never get any hidden corrosion damage that way.

 

[scubadada]

Avelo Mode is now available on the Shearwater Teric, Peregrine TX, Perdix 2, and Tern TX. It is also available on the Scubapro G2 console.

 

[EdMcNeill09]

spraying Rhino Liner on aluminum tanks sounds like about the worst thing they could do.
They should just strip the tanks down to bare aluminum and let them breathe, who cares how they look? They would never get any hidden corrosion damage that way.

These are Carbon Fiber wrapped over thin walled aluminum. Taking the carbon fiber off the tanks would remove the strength of the cylinder. Spraying the carbon fiber wrapping with Rhinoliner protects the carbon fiber from abrasion that is looked for in the annual visual inspection. Your concern is really valid when thinking of traditional aluminum tanks that have been painted. When it comes to carbon fiber tanks the concerns during the annual visual inspection are different.

The RhinoLiner on the Carbon Fiber tank is a total winner. I dive Avelo regularly on charters and haul the tanks in my truck. They get handled exactly like my aluminum tanks and over the past year I've noticed some scuff marks on the Rhino Liner but no cuts or other penetrations.

 

[EdMcNeill09]

For balance;

• Avelo kit is expensive; costing ~$3000 more than traditional kit
• Requires crossover and buoyancy training at additional cost
• Buoyancy isn't an issue; training is the problem
• Weight differences are overstated
• There is very little positive buoyancy available on the surface; this could be dangerous.
• The equipment is novel; other divers not immersed in the Avelo system would struggle to rescue an Avelo diver (no elephant's trunk, no inflator, little buoyancy)
• Per dive, Avelo kit would be far more expensive to rent and fill than traditional kit.
• Relies upon a battery to sink -- traditional kit would be a 2 second dump.

Avelo is expensive. No question about that. I'm hoping that over time the cost difference will shrink.

You do need training to dive Avelo. I trained a local course director recently who is telling everyone to basically forget what you know about diving and approach this with fresh eyes. The training doesn't take long though. It's a 2 hour elearning and a one day class with two dives.

Weight differences are significant but vary amongst divers. For me the weight difference from a Scubapro Hydros (8.8Lbs) & 16 lbs is really noticeable. So basically 25lbs of weight plus the tank vs 5 lbs of lead and the Avelo System. I don't have actual numbers for you but figure it's 15-20 lbs lighter than standard in my case.

Getting positive post dive involves releasing the water from the hydro tank. depending on the how much gas you used you should be 4-6 lbs positive. If you need more you can inflate your SMB for another 6-8 lbs of positive lift.

Rescuing an Avelo Diver is pretty easy actually as they should be very close to neutral throughout the dive. If you are on standard scuba and pick up a 4lb weight off the sand what do you do? you add a little air to your bcd. Easy. The rescue exercise for Avelo is a little different in that there is a valve to open at the surface but even without knowing this you could perform a rescue.

Renting Avelo is a little more expensive than standard scuba but this varies by shop. It is new and a lot of shops have a lot of $ invested in gear. I expect the cost of renting gear will decrease to the point of matching the rental rate of a premium gear package over time.

 

[EdMcNeill09]

I would be curious to see what those rescues look like. How fast can this system add ballast if you need to go fetch another dive from the surface? It soesn’t seem suited for a hot drop entry, since you are relying on a water pump pushing against 4000 psi. Are you going to be able to creat enough lift to bring up an unconscious diver in a traditional rig?

Why would you need to fetch a diver from the surface? The only scenario I can think of is teaching an OW student in standard scuba. In this situation I wear Standard Scuba. Bringing an Avelo diver down is a piece of cake as long as they are weighted properly. This is part of predate work.

Hot drops are super easy on Avelo as you start at approximately 1 lb positive. A giant stride off a boat takes you 4-5' down. You just kick down while you run the pump. I do this pretty regularly and honestly it's a blast. I do this regularly to hook the boat up to the mooring. It's actually easier than free diving in a wetsuit for the mooring ball.

If you are rescuing a diver in traditional gear the process is the same as if you are in traditional gear except that you don't have a bcd of your own to inflate. Generally you are going to use the divers bcd for inflation. If they have a bcd incapable of inflation, for example if their shoulder dump valve has blown off, you would remove some of their weights to bring them to the surface. You also have the option of venting water from your hydro tank to add 2-4 lbs of lift. The challenge will be to avoid a buoyant ascent so in this case you probably want to keep everyone as negative as you can manage for the swim up. The only times I've ever faced an unresponsive diver at the bottlom is when I teach Rescue Class. I'm sure PADI and other agencies will be updating Rescue Class and Their IDCs to cover this.

 

[EdMcNeill09]

My point was that an overweighted Avelo diver is similar to a traditional diver risk-wise, so I wouldn't expect a big blow-back against Avelo after someone jumps in overweighted.

Traditional divers (many of whom are also overweighted) aren't dying left and right after forgetting to hook up their BC, and I highly doubt they are orally inflating or connecting the inflator hose. They simply kick back to the ladder, which would also work for an overweighted Avelo diver. To your point though, if we're assuming someone capable enough to react beyond "just kicking", there is still little difference, as the Avelo diver could simply drop lead.

Failing to connect an inflator hose on a traditional bcd does cause deaths. I don't know the numbers on this but was told in my IDC that it was a significant cause of diver deaths. Having done this myself I can see how easy it is to forget.

Proper weighting for an Avelo Diver is a significant focus during training as a one lb difference makes a huge difference for the experience. Getting it right is crucial. When Avelo divers certified elsewhere come and dive with on Oahu I calculate their weight needs and check it on our first dive together.

During Avelo training there is significant focus on checking the SPG while running the pump to ensure the pressure is rising and not exceeding 300 bar. When pressure isn't rising it is usually because the valve is open so no water is going into the tank or that the hose isn't properly attached. A third potential problem (very rare) is that the pump is failing. Both of the first two issues can be handled by a diver or by a buddy. Attaching the hose yourself is a bit tricky but manageable.

 

[CT-Rich]

Why would you need to fetch a diver from the surface? The only scenario I can think of is teaching an OW student in standard scuba. In this situation I wear Standard Scuba. Bringing an Avelo diver down is a piece of cake as long as they are weighted properly. This is part of predate work.

I meant, how long would a diver in an Avelo system at rest on the surface (6 lbs buoyant) take to become negative to retrieve a diver on the bottom. I am assuming the electric pump needs force water into the tank/bladder system to become neutral.

Hot drops are super easy on Avelo as you start at approximately 1 lb positive. A giant stride off a boat takes you 4-5' down. You just kick down while you run the pump. I do this pretty regularly and honestly it's a blast. I do this regularly to hook the boat up to the mooring. It's actually easier than free diving in a wetsuit for the mooring ball.

If you are rescuing a diver in traditional gear the process is the same as if you are in traditional gear except that you don't have a bcd of your own to inflate. Generally you are going to use the divers bcd for inflation. If they have a bcd incapable of inflation, for example if their shoulder dump valve has blown off, you would remove some of their weights to bring them to the surface. You also have the option of venting water from your hydro tank to add 2-4 lbs of lift. The challenge will be to avoid a buoyant ascent so in this case you probably want to keep everyone as negative as you can manage for the swim up. The only times I've ever faced an unresponsive diver at the bottlom is when I teach Rescue Class. I'm sure PADI and other agencies will be updating Rescue Class and Their IDCs to cover this.

 

[EdMcNeill09]

@gordonscuba The promotional footage/images I've seen show weights strapped on to the based of the hydrotank. Obviously you can wear a weight belt with any buoyancy system, but there are also pockets, at least on some, and I was wondering if Avelo's system for mounting weights on the hydrotank was designed for in water removal. Looking at the pictures, I feel like you could reach it with a little work, from there it's just a question of how easily it comes off/out.

Tank mounted weights are usually located there for trim, as I understand it, and I've never seen ditchable trim weights, so it wouldn't shock me if Avelo's weight mounting is non-ditchable.

Not a huge difference either way, of course. I'm just curious. I suspect if someone were to load down a massively excessive amount of weight, they'd end up putting at least some of it in place they could reach, if only because it has to go somewhere, thus allowing them to ditch some fraction and stop a sink. Whereas if someone who was neutral at 0 put the 3/4lbs the tank weight system usually seems to hold (based on user comments on here), they could overcome that by finning up and buying their dive buddy a beer later in atonement.

There are two basic places weights are added to the Avelo System. The most popular is the cage at bottom of the tank. Some divers prefer to put some weight on their waist strap for better trim.

Dumping weight isn't really a concern with Avelo. There are no sudden changes in buoyancy. There is no air volumes that compress or expand on the system causing a need to rapidly change your buoyancy. On Avelo your buoyancy is essentially the same from 15' to as deep as you want to go. On traditional scuba you inflate and deflate as you descend and ascend. I had a diver once with an old BCD with 18lbs of lead who had her shoulder dump valve blow off at 70'. Fortunately she was right near the mooring line with her husband. Together they returned to the boat. This is the type of scenario where you need ditchable weight and the sort of situation that can't happen with Avelo.

Making sure an Avelo Diver is properly weighted is an emphasis in all Avelo training. Getting it right is key to the experience and for safety.

 

[lowwall]

I meant, how long would a diver in an Avelo system at rest on the surface (6 lbs buoyant) take to become negative to retrieve a diver on the bottom. I am assuming the electric pump needs force water into the tank/bladder system to become neutral.

In a life or death emergency, you can swim down 6 pounds positive. But an Avelo diver can only be 6 pounds buoyant after finishing a dive with a nearly empty tank, surfacing and blowing any ballast water. Attempting a rescue with low gas and when already Nitrogen loaded is not a good idea no matter what's on your back,