Flying your unit manually .

zoo_diver

I think the point is using the computer between your ears as the primary means of controlling/monitoring what you are breathing and the computer on your wrist as a back-up. I understand the analogy of having a car and pushing it instead of using the engine, but I prefer the analogy of...well actually I can't think of a good one, but if I could, it would be right here <--------->. Like rule 10 says, with an eCCR, role with a low setpoint and fly it manually at something higher.

DeepBlueInnovation

I gotta say, I still don't see the point. From what little I know about diving a kiss it makes sense; there is a constant flow so that not much 02 needs to be added manually - it is therefore a lot less intensive to fly the unit manually. On an eccr, if you are going to fly it above set point you need to constantly be adding 02 and in my experience this detracts from the dive. IMHO if you want to fly a unit manually - do it the easy way and buy a mccr.

Alternately, if you don't trust yourself that much build a hybrid that operates as a mccr but has a solenoid kick in if set point drops to a sufficiently low level.

FWIW, the single most important piece of safety equipment on a Rebreather is the HUD - it immediately lets me know if something is wrong. What if the HUD fails? Well, one of the things I like about an eccr is the solenoid is that I can hear it fire, and I can say from experience that you do notice when it doesn't!

Disclaimer: practicing all safety skills on a regular basis is vital to build the muscle memory, I just personally wouldn't fly my unit above set point the whole time.

tibby

If nothing else at least you save your batteries by staying ahead of the solenoid.
Tibby

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Does the voice of reason change when you add helium to the mix?...hmm

decoweenie

Sure, buy a car and push it to save gasoline cost...

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"...after a while you get bored offering advice to a bull that like to keep butting the fence with its head rather than walking through the open gate..."

- Rebreather World PM

Gilles

This is a matter of personal choice, which in my view, is a fairly effective (because unexpected solenoid sound indicates impending complacency) way to build the required eCCR monitoring skill.

This topic is like .

If you don't like doing it (manually flying eCCR), then don't!

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Gilles
http://www.dirrebreather.com

Drmike

I find it interesting that people prefer to rely on the 'computer between their ears' rather than a simple bit of electronic circuitry. I can understand the thought process behind that - but I still find it interesting seeing as much of the time its the computer between the ears that gives the highest danger to a diver. To me I know on a big dive if we have all the safety back ups and protocols in place its my mind that is the weak link

Keeping calm and panic free, thinking/acting logically, and multi tasking during high stress/ distracting situations. These are the things real computers do well at and the ones between our ears do badly at.

Ive noticed that in many situations the battle to survive underwater is a mental battle rarely a technological one*.


*many technological failures aren't life threatening yet become life threatening when we lose ground on the mental front and panic/react wrongly.

I don't have much of a preference either way mccr or eccr, either way I still monitor just as much.

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Cave diving is a sport
Wreck diving is a sport
Diving in general is a sport

'Rebreather diving' is not a sport
its the delusional obsession with a highly dangerous and often inappropriate piece of equipment

PCDiver

On the Vision you have a hud and a buzzer, but you use the sound of the solenoid as an alarm bell ??? With a thick hood I can hardly hear the solenoid firing.

DeepBlueInnovation

Different units, and different diving conditions. Listening for the solenoid was something drummed in during training - I am not sure about other units but it has a distinctive click behind my left ear on the Prism (it is designed so the solenoid is outside the head and will vent into the water not into the loop in the case of a failure).

I don't think the water temperature in Perth will necessitate quite as thick a hood as it will in Belgium

David Pye

Weelllll, I did have a choice, arguably - I could have bought an eCCR if I wanted one

Padowan

Not wanting to throw petrol on the bonfire, but to quote "Rule 10"

10 – Fly your unit manually using the electronics as a safety net. I strongly believe that anything man made is not perfect – we can spend billions on developing electronics be they for space ships, airplanes, rockets or nuclear power stations and we all know they go wrong and cause fatalities – a fraction of development cash is spent on Rebreathers compared to the above so let’s use them as a safety net.

Is man-made things are so "imperfect" why the hell would you want to rely on one for a backup? What happens if it fails then, when you really need it?

And my other big gripe with this, is if you are doing the work of the solenoid and injecting manually, then the solenoid is never being "put through it's paces", it hardly ever fires, and hardly ever gets moved through it's stroke, so when it does fire, cos you were complacent and distracted by something, it can stick open, giving you something else to look at?! I have seen solenoids stuck open a couple of times (not on my auto-operated YBOD, but on a manually-flown Meg)

I got very in tune with the frequency and duration of the injections on my YBOB very early on, and I am still well aware of the injections based on depth, changes in depth and workload.

I know my unit, I have a HUD and a buzzer and a solenoid and some simple circuitry to control it and 2 handsets and a brain - I use them ALL on all dives (well maybe I don't "use" the buzzer, but it's there "running" in the background) and am quite capable and confident of continuing or aborting the dive with the loss of pretty much any 2 of them, and I don't have to use my finger on a button.

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