Review Diving the Avelo System

[inquis]

I am not clear why Carbon fiber tanks would be of interest. You need to displace the density of the tank and air. The big advantage of steel over Aluminum is that steel offsets the extra lead required to make tank sink.

The pump and battery are heavy. The carbon fiber tank offsets much of that negative buoyancy. As it is, it's been reported in other threads that some divers in a rash guard might need "buoyancy pads" to further offset the negative buoyancy (since a wetsuit isn't there to do that).

 

[lowwall]

The pump and battery are heavy. The carbon fiber tank offsets much of that negative buoyancy. As it is, it's been reported in other threads that some divers in a rash guard might need "buoyancy pads" to further offset the negative buoyancy (since a wetsuit isn't there to do that).

By their own measurements, the combined tank and Jetpack (harness, pump and battery} is 1 kg positive without gas. Add gas and a reg and it's around 2.5kg (5 pounds) negative at the start of a dive.

I just realized I forgot to account for the gas weight in my last post. That means you shouldn't need any lead with the Avelo system which increases its weight advantage to around 5 pounds versus my example setup of BP/W + HP80. I'm going to edit that post now.

 

[inquis]

Add gas and a reg and it's around 2.5kg (5 pounds) negative at the start of a dive.

Yep, no way that would work without the carbon tank. The goal is to be +1 kg (+2 lb) overall at the beginning of the dive. Salt water is also useful, as that adds 2-2.5 kg (4.5-5.5 lbs) to ones personal buoyancy.

 

[Wibble]

300 bar tank. Has anyone here ever received a 300 bar fill?

I started diving with a 12 litre 300 bar steel tank. This was considerably heavier than a 12 litre 232 bar steel tank but rarely ever had above a 250 fill due to the time it took to fill it, let it cool, top it off to beyond 300 bar so it cools to 300 bar.

In the mass market of recreational diving in warm water locations using 232 bar steel cylinders, you rarely ever get a fill beyond 200 bar, let alone close to 232 bar. They simply don’t have time to fill to 250 bar, cool, then top off.


But Avelo are selling the dream. Very low numbers of premium high paying customers prepared to pay top dollar for the extremely proprietary specialist equipment, training and pandering.

Dive shop purchasing normal equipment: BCD and 2 x ali80 tanks for $500 if buying in bulk. Avelo: $3k? for 2 x “JetPacks”, harness, spare batteries, plus 300 bar compressor, battery charging station, longer tank filling times, etc.

One other issue is the internal tank bladder will probably reduce the gas filling speed due to temperature restrictions.

 

[CT-Rich]

Looking at how the Avelo works, I have a couple of questions that seem significant. The primary one is gas remaining. The system automatically corrects buoyancy by adding/ removing water from inside the cylinder, changing the volume of the gas in the bladder. A standard tank has a fixed volume and you monitor your supply by watching the pressure drop. This system, from the material I've seen, has a variable volume bladder and lowering tank pressure.

It seems like there is a lot of added complexity to monitor gas remaining because a change in depth will affect your bladder volume. Second, you are pumping water inside your high pressure cylinder. I can't see anyway to inspect the inside of the cylinder without a complete disassembly of the unit. does the system have a filter to keep foreign material from the inside of the tank? This seems very complicated system for a very minimal benefit. If weight is a serious issue for a diver with back problems, a simpler solution would be to don the tank in the water or switch to side mount.

 

[inquis]

300 bar tank. Has anyone here ever received a 300 bar fill?

The gas is filled at less than 300 bar for an Avelo system. This leaves room (pressure-wise) to take on the ballast.

For example, a 233 bar gas fill gives the same amount of gas as an AL80 (including compressibility). If pressurized to 300 bar by the ballast pump, the water taken on would weigh about 1.3 kg (2.8 lb). This figure includes the adiabatic heating effect on pressure and compressibility.

 

[lowwall]

Looking at how the Avelo works, I have a couple of questions that seem significant. The primary one is gas remaining. The system automatically corrects buoyancy by adding/ removing water from inside the cylinder, changing the volume of the gas in the bladder. A standard tank has a fixed volume and you monitor your supply by watching the pressure drop. This system, from the material I've seen, has a variable volume bladder and lowering tank pressure.

It seems like there is a lot of added complexity to monitor gas remaining because a change in depth will affect your bladder volume. Second, you are pumping water inside your high pressure cylinder. I can't see anyway to inspect the inside of the cylinder without a complete disassembly of the unit. does the system have a filter to keep foreign material from the inside of the tank? This seems very complicated system for a very minimal benefit. If weight is a serious issue for a diver with back problems, a simpler solution would be to don the tank in the water or switch to side mount.

It's a manual system, not automatic. To add ballast, you press a button and the pump runs for long enough to add about a pound. You only need to do this for the initial descent and a couple of times during the dive to compensate for consumed gas. The whole point of the system is there is no change in bouyancy due to level changes. Removing ballast, which will normally only be done once you surface, is also manually controlled.

I had the same concern about gas remaining. They initially dealt with this by adopting a rough rule that ensured you had adequate gas at the expense of some bottom time, but since then they have worked with Shearwater to introduce a tracking mode to some of their AI models so you get a reasonably accurate estimate of gas remaining.

AVELO MODE

Avelo Mode is a new feature available on compatible Shearwater dive computers. Contact an authorized Shearwater dealer to get an unlock code for Avelo Mode.

shearwater.com

If you don't already have one, add the price of a Shearwater AI computer to the system cost. Plus $99 to unlock the mode.

I'm with you on the tank inspection issue. I also imagine using this in a silty environment is a bad idea. But look at it from an operational perspective. These will only be sold or rented through "Avelo Dive Centers" which are required to have an Avelo trained technician on hand. The cylinders have an annual inspection requirement which will need to be done by one of these techs. These techs can remove the bladder which means they can get inside the cylinder to inspect and clean it when needed. I kind of doubt they will ever support DIY service of the tank. But that's not an issue for their market of rentals and the occasional rich guy.

I still think this is going to fail - or at best end up as a small niche market at a handful of overpriced dive destinations - once the seed and any VC money runs out. It's a lot of cost and complexity for marginal benefits. A big obstacle is the additional training that is required and the fact that they can't issue OW certs or do DSDs for people trained on this gear because it doesn't meet the technical requirements laid out in the WRSTC standards. I can just imagine the lobbying efforts going on behind the scenes regarding this issue.

 

[scubadada]

To add to what @lowwall posted:

When I took the RAD and 2 additional guided dives in December 2023, the gear included a hosed Scubapro G2 computer running Avelo Mode. The screen included % gas remaining, very easy. I did 3 additional independent dives without a computer running Avelo Mode. You simply use the maximum pressure after the 1st pump to judge gas use, also very easy. For my 6 independent dives this October, I already had a Shearwater Teric computer and downloaded the Avelo Mode prior to the trip. My home screen displayed gas % remaining, gas pressure, work (RMV), and buoyancy. I posted a Shearwater and an Avelo graph in my follow up review

Review Post in thread 'Diving the Avelo System'

Nov 17, 2024

This is a follow up to the initial review I posted on Jan 2, 2024

Review - Diving the Avelo System

The Avelo System is innovative diving equipment that allows you to dive differently than with traditional gear. The Avelo System consists of the Jetpack and the Hydrotank. The Jetpack is a backplate, harness, battery, and pump. The Hydrotank consists of a flexible bladder holding the gas and a...

scubaboard.com

My wife and I returned to Bonaire for two weeks, October 16-October 30. I rented Avelo gear for 2 days and did 6 more dives. I have somewhat limited mobility of my right shoulder and had some difficulty reaching the pump button on the Jetpack. Avelo supplied me with a modified Jetpack that was very easy for me to use. It moved the button about 4 1/2 inches to the side and about 1 1/2 inches higher. I downloaded the Avelo Mode to my Shearwater...

• scubadada

• 
• 

Avelo Mode is currently available on the Shearwater Teric and Peregrine TX. It will also be available on the Tern TX and Perdix 2 soon. Shearwater and Avelo announced a partnership at the recent DEMA meeting

Shearwater Research & Avelo Labs Announce Groundbreaking Partnership

This collaboration aims to drive the advancement of diving systems and human performance, uniting Shearwater’s technical expertise with Avelo’s groundbreaking innovation.

shearwater.com

All service must be performed by a certified Avelo technician. Visual inspection is performed yearly and includes the rigid shell and the bladder. The bladder is replaced every 5 years. Hydrostatic testing is performed every 5 years. Pump service is done every 2 years. Obviously, if you rent gear, as I occasionally plan to do, all service is invisible. I paid $110/day in Bonaire for a Jetpack, 3 Hydrotanks, 2 batteries, and weights. A 300 bar DIN regulator set is included in the rental, but I used my own.

 

[Germie]

300 bar tank. Has anyone here ever received a 300 bar fill?

I started diving with a 12 litre 300 bar steel tank. This was considerably heavier than a 12 litre 232 bar steel tank but rarely ever had above a 250 fill due to the time it took to fill it, let it cool, top it off to beyond 300 bar so it cools to 300 bar.

In the mass market of recreational diving in warm water locations using 232 bar steel cylinders, you rarely ever get a fill beyond 200 bar, let alone close to 232 bar. They simply don’t have time to fill to 250 bar, cool, then top off.


But Avelo are selling the dream. Very low numbers of premium high paying customers prepared to pay top dollar for the extremely proprietary specialist equipment, training and pandering.

Dive shop purchasing normal equipment: BCD and 2 x ali80 tanks for $500 if buying in bulk. Avelo: $3k? for 2 x “JetPacks”, harness, spare batteries, plus 300 bar compressor, battery charging station, longer tank filling times, etc.

One other issue is the internal tank bladder will probably reduce the gas filling speed due to temperature restrictions.

And the need of training is very very questionable. For myself I don't need training for this, I will be able to learn it in 1 dive, for sure. It is no rocketscience. It looks like diving a drysuit, a course can be ok if you are unsure, but is not a requirement.

And I read about 2lbs positive before a dive. That is really nothing if you are in big waves with current.

And also important, here no 300 bar fills in my backyard.

 

[SouthernSharktoothDiver]

@Germie is the drysuit course not necessary? I’d heard the taught you how to pull out of an uncontrolled ascent due to shifting bubble, which seems important