Diving the Avelo System

My wife and I took a two-week trip to Bonaire in mid-December, where we signed up for Avelo training offered by Dive Friends. It was indeed an interesting experience.

The Avelo System is new and innovative diving equipment that allows you to dive differently than with traditional equipment. The tank system, called the Hydrotank, consists of a flexible bladder that holds the gas inside a rigid outer shell. The Hydrotank can hold up to 106 cu. ft. of gas if filled to its rated pressure of 300 bar/4350 psi. The harness, back plate, pump, and battery are called the Jetpack. The system weighs somewhat less than traditional equipment with an AL80 cylinder.

The unique feature is that you don't need a buoyancy compensator. The tank has an internal bladder filled with breathing gas. One controls buoyancy by pushing a button mounted on the tank that pumps water into the cylinder, compressing the air-filled bladder. Their website says that their tank is "buoyant and can become lighter or heavier by using water from its environment. Its operating concept is like a submarine that adds or removes water to maintain neutral buoyancy." There is no compressible/expandable bubble with the Avelo System as there is with a BC, the factor most responsible for changes in buoyancy associated with changes in depth when using a BC.

Bonaire is one of only three destinations (another is on Southern California's Catalina Island, the other is in Sydney, Australia) where they offer training. We took a one-day, two-dive Recreational Avelo Diver (RAD) course, and the following day, we made two additional guided dives. Later in our visit, we rented Avelos for three independent dives, for seven dives total.

Training

The RAD course starts with a well-designed eLearning exercise in three sections: concepts behind traditional and Avelo diving, the components of the Avelo System, and the procedures for using the Avelo System. After a review of the eLearning information and a detailed demonstration for assembling and using the Avelo equipment, we were off for our two certifications.

Then, we were off for two certification shore dives at the Something Special site, across the street from the Dive Friends dive shop. The first dive was mainly getting used to the Avelo System, which included a weight check at the surface, achieving neutral buoyancy, and swimming around at different depths.

I needed four pounds of weight in the Hydrotank base to adjust buoyancy. My wife used three. I was pleased with the ease of achieving neutral buoyancy and depth independence. The second dive, we worked on our skills: doffing and donning, simulated pump running, simulated loss of ballast water by purging at depth, a shared gas ascent, and deploying the integrated SMB at the surface. The two simulated failures were easy to deal with. Their extra weight was not difficult to swim with, and one could always open the purge valve. Loss of ballast water only resulted in minimal lightness, and swimming was still not difficult. For either failure, one would calmly terminate the dive. After completing the second dive, we were RAD-certified.

We made two additional guided dives on the second day to become more familiar with the system. Dive Friends requires four guided dives before they rent Avelo for independent diving. Our instructor and guide, Stephanie, was phenomenal. We made the dives with a modified Scubapro G2 dive console that includes the Avelo Mode. It was interesting to see our dive profiles, gas consumption rates, and where we fell in the optimal buoyancy range.

Several days later, we rented Avelo gear for a threedive day. We picked up two Jetpacks, six Hydrotanks, and four batteries, and off we went. We were slow setting up the system but improved with practice. The dives went well; we had excellent neutral buoyancy, controlled by our breathing and gently swimming up and down. I appreciated the equipment's lighter weight. I have a relatively low gas consumption rate to begin with. Though my gas consumption was improving slightly over my three independent Avelo dives, I was unable to get down to my usual average gas consumption rate. Gaining more familiarity with the equipment may help.

Is Avelo the diving of the future?

I don't know. They need to have far more training centers but say they will open several Avelo Dive Centers in 2024 to offer professional and recreational training and serve as hubs for expansion. Avelo equipment will be available for sale later this year, and I'll be interested in seeing the price set.

I also think it will be important for Avelo's success to have dive computer manufacturers add an Avelo Mode on their computer platforms.

Our experience with the Avelo System in Bonaire was interesting and enlightening. The two-dive RAD course and two additional guided dives cost $700 each. The daily Avelo rental was $110 per person.

I'm glad I was certified and had additional experience with Avelo. I'm not sure I will be diving the Avelo System again. I am a reasonably experienced diver with good buoyancy control and gas consumption. The advantages of Avelo are less for me than they might be to others. Avelo is an interesting system that has made its way to being available for the diving public to experience. Time will tell how this eventually works out. I think most of us are skeptical of changes in devices we are used to. Some of them are successful, some of them are not. As a child, my prized possession was a batterypowered transistor radio. Today, I carry a smartphone that can do wonders.

- Craig Wood, Florida

Undercurrent Comments

The Avelo system is an innovative product looking for acceptance by all levels of divers.

One common criticism, often by divers who have not tested it, is that it offers a solution to a problem divers don't have That problem, while never clearly defined, seems to be that a well-trained diver doesn't have buoyancy problems and doesn't need the Avelo.

Perhaps But in a Zoom podcast, Dan Orr was quite pleased with how he could rise from the depths to the surface with an Avelo and did not need to adjust his buoyancy along the way It made his dive a little easier.

The Avelo system weighs less than an 80 cu ft tank, what the manufacturer sees as its rough equivalent Furthermore, a diver can wear less weight and doesn't need a cumbersome BCD to wear or lug around The Avelo system can contain your weight so that a weight belt won't be required Because you need less weight (and have less drag), Avelo claims it will decrease your air consumption Experienced divers will surely have less improvement than divers just getting started.

Bear in mind, because the human body is incompressible, its buoyancy is not affected by depth A BC is conventionally used to compensate for the changes in buoyancy of the wetsuit as it gets compressed, and the changing mass of the air remaining in the tank.

That said, an Avelo system has its disadvantages

1. Setting up and changing over between dives is more time-consuming than handling traditional gear.

2. The standard 10-liter tank is very tall and uncomfortable to don on benches or a boat seat.

3. On the surface, a filled BC will raise your head clear of the water, making it easier to be spotted from an RIB. With an Avelo, you may ride lower and need to keep breathing from your regulator or use a snorkel in choppy water.

Our Avelo tester said, "We both felt perfectly comfortable on the surface after the Avelo dives and did not need a snorkel, but we may want one in certain circumstances. When drift diving in SE Florida's big seas, I sometimes breathe through my regulator while waiting for pickup in my standard back inflate BC and do not carry a snorkel."

4. As they say, Keep it Simple, Stupid. Adding more essential items to gear means more can go wrong. The Avelo has a mechanical pump and purge, an electrical switch, a battery, and water seals, adding to things that can go wrong underwater. If the pump doesn't function, you can't add water for ballast.

Buoyancy will increase so slowly that it shouldn't be a problem and can be controlled by swimming. Craig Wood added, "For any failures, one would assess the ramifications and decide whether to call the dive, just like you do with standard equipment. A stuck BCD inflater may be a more dangerous equipment failure that could lead to an uncontrolled ascent if one fails to disconnect the inflator hose or vent their BC adequately."

5. The Avelo has no pockets for storage. One could add pockets to the waist belt wetsuit or drysuit. In tropical waters, some divers wear shorts with pockets.

6. While you carry less weight than with conventional gear, in an emergency, you can't drop your weights if you have placed them in the slots of the tank boot.

If this is a concerns, one can wear a weight belt with weights or releasable weight pockets, though this eliminates one advantage of the Avelo system.

7. The Avelo cannot provide immediate buoyancy, as can a BCD, either with an inflator or adding air orally, to assist a rapid, controlled ascent. With an Avelo, you would vent your ballast as you swam to assist your ascent.

What's the Future?

Only time will tell if the Avelo System catches on. While the price has not yet been set, it will not be inexpensive. If divers travel with the Jet Pack, dive operators will need to have the Avelo tanks available. If divers rent the entire system at their destination, it will drive up the cost of a dive trip. There are plenty of divers willing to spend big money for diving, and Avelo only needs a share of that market. The Avelo company is banking on divers finding the advantages over current gear enough to make the switch.

We shall see.

- Ben Davison

For an excellent video of the Avelo System (featuring its developer Avihad Cahana and Dan Orr, who was trained with the system) presented by Ken Kurtis of Reef Seeker, go https://tinyurl.com/ywav7k5j. The Avelo website is https://diveavelo.com