One dead, one missing (since found), 300 foot dive - Lake Michigan

[beester]

Not a rebreather diver but I've often thought that there should be some battery powered way to put a little positive pressure on the upstream side of the mouthpiece. But, one more thing to go wrong.

I once read something like this, when discussing the demise of Dave Shaw, but it would probably add additional complexity to an already complex machine... I rather first have good solid state O² sensors than this ;-)

 

[KevinNM]

It's illegal for me to dive a CCR so I have limited knowledge. Is the corrective action while deep underwater to increase O2 injections or are you just screwed because there's no way to purge the CO2 without causing further gas mix problems at depth?

In this case it isn't the CO2 in your breathing gas, it's the CO2 in your blood. Your scrubber can be working fine but your lungs can't dump it as fast as you generate it. It becomes a vicious cycle. There was a presentation by this by an expert I saw, but at this point can't remember who.

 

[Dan]

I once read something like this, when discussing the demise of Dave Shaw, but it would probably add additional complexity to an already complex machine... I rather first have good solid state O² sensors than this ;-)[/QUOT

Since you need to suck & blow to circulate the gas through the rebreather, including through the CO2 scrubber, I assume, I imagine the scrubber bed preparation would be very important too. If the bed is packed too tightly, the pressure drop would be too high and you would have high WOB. If the bed is packed too loosely, gas channeling could occur resulting in poor CO2 absorption efficiency and CO2 being not completely absorbed and recycled back to the diver during inhaling. If the bed got wet, it turns into a cake, then you would suck a vacuum.

 

[Renee3420]

1 dead, 1 missing following scuba diving accident in Lake Michigan, MPD launches criminal investigation

Not Good. Sorry to hear about the loss of two people.

 

[Renee3420]

Who owns the vessel?

 

[michael-fisch]

Proper scrubber design can do a lot to decrease WOB. An axial scrubber usually has the gas having to go through close to 8" of sorb. Even using an 8/92 heliox the resistance caused by that amount of sorb is considerable. Radial scrubbers present a much larger surface area and much shorter distances through the sorb, in my case about 1.75" causing a great reduction in WOB. Thats why all rebreathers designed for deep use use radial scrubbers exclusively. At 200' any scrubber (using enough Helium) will work ok, at 400+' axial scrubbers can cause serious problems even using Heliox, and at 660' I don't know of anyone surviving the use of a fully packed axial scrubber.

Michael

 

[jale]

Proper scrubber design can do a lot to decrease WOB. An axial scrubber usually has the gas having to go through close to 8" of sorb. Even using an 8/92 heliox the resistance caused by that amount of sorb is considerable. Radial scrubbers present a much larger surface area and much shorter distances through the sorb, in my case about 1.75" causing a great reduction in WOB. Thats why all rebreathers designed for deep use use radial scrubbers exclusively. At 200' any scrubber (using enough Helium) will work ok, at 400+' axial scrubbers can cause serious problems even using Heliox, and at 660' I don't know of anyone surviving the use of a fully packed axial scrubber.
Michael

There is a guy in France diving regularly in the 200M range using a double "home-made" rb with axial scrubber.

 

[Marie13]

Who owns the vessel?

Double Action Dive Charters. Already mentioned early in the thread.

 

[Cert1967]

Who owns the vessel?

Interesting question. How motivated are you? Information for a starting point - read on.

I don't believe that WI boat registrations are available - searchable - online. There are paid services that will do the leg work for a fee. A FOIA request would probably work, perhaps a phone call to

Registration and titling information for boats, snowmobiles, ATV/UTVs and OHMs - Licenses, permits and registrations - Wisconsin DNR​

A frame grab from the 08JAN2019 you tube post shows the Alma's WI registration number as WS7650HN. Note the blue decal, to the left of the WI registration number - perhaps it is a current year tag?

At some point, the City of Milwaukee police report should available, via a FOIA request, for a minimal fee.

Searching "ALMA" at the WI department of financial institutions produces a number of "ALMA" returns. Contributing to the number of hits - Alma is a town in Wisconsin and it is a river city.

Double Action Charters, LLC is an Illinois entity - 05228972. I could not find a "Double Action" in the WI or IN search - perhaps you can.

Double Action Dive Charters. Already mentioned early in the thread.

Perhaps not that simple. I suspect that the ownership of the marketing entity (DAC) and the boats, may be more complex than at first glance.

 

[Marie13]

Interesting question. How motivated are you? Information for a starting point - read on.

I don't believe that WI boat registrations are available - searchable - online. There are paid services that will do the leg work for a fee. A FOIA request would probably work, perhaps a phone call to

Registration and titling information for boats, snowmobiles, ATV/UTVs and OHMs - Licenses, permits and registrations - Wisconsin DNR​

A frame grab from the 08JAN2019 you tube post shows the Alma's WI registration number as WS7650HN. Note the blue decal, to the left of the WI registration number - perhaps it is a current year tag?

View attachment 527739

At some point, the City of Milwaukee police report should available, via a FOIA request, for a minimal fee.

Searching "ALMA" at the WI department of financial institutions produces a number of "ALMA" returns. Contributing to the number of hits - Alma is a town in Wisconsin and it is a river city.

Double Action Charters, LLC is an Illinois entity - 05228972. I could not find a "Double Action" in the WI or IN search - perhaps you can.

What are you aiming for?