question about SCUBA

[Rogue-OP]

Hello,

I'm an Industrial (aka Product) Design student from SJSU and have a few questions for the actual divers here. For my project this semester I am taking a look at redesigning a SCUBA / Rebreather unit and have a question.

Most SCUBA tanks are rated around 60 mins of use and rebreathers can go even longer.

My question is, is there a use for a device that will last you 20 minutes?
Are there scenarios where the benefit of a smaller tank would outway the time constraint? Are there situations where you really only need 20 minutes to get whatever done? Could you see this as being more useful in a military application?

Thanks,
-Dav

 

[ucfdiver]

Hello,

I'm an Industrial (aka Product) Design student from SJSU and have a few questions for the actual divers here. For my project this semester I am taking a look at redesigning a SCUBA / Rebreather unit and have a question.

Most SCUBA tanks are rated around 60 mins of use and rebreathers can go even longer.

My question is, is there a use for a device that will last you 20 minutes?
Are there scenarios where the benefit of a smaller tank would outway the time constraint? Are there situations where you really only need 20 minutes to get whatever done? Could you see this as being more useful in a military application?

Thanks,
-Dav

Lots of the deep dives you hear people talking about doing recreational aren't even 20 minutes. SCUBA tanks are rated to last CU FT SIZE / SAC Rate * Depth (in ATM)....An AL40 likely wouldn't last 60 minutes anywhere, a HP130 would last well over 60 minutes for most recreational depth diving.

I cannot using a rebreather that lasted 20 minutes. The benefit would be far less than the cost and additional risk and/or training required for me. I think a 20 minute dive is a waste of time. If my dive doesn't last at least an hour or more, I lose interest very fast.

 

[elan]

Are there situations where you really only need 20 minutes to get whatever done?

Yeah to do the buoyancy check and check that the dry suit is not leaking

Our average rec deep dive lasts 50 mins and an average shallow one around 80, last time it was 107 min. You can go from here.

 

[Cave Diver]

My question is, is there a use for a device that will last you 20 minutes?

It seems to me that this is akin to designing a solution, then looking for a problem to fit it.

Several factors can affect the length of a dive, including depth.

There are a variety of tank sizes available, all the way from a 3 cft spare air cylinder, 6 cft argon bottles, small pony bottles @ 9, 12, 19 etc. cft, deco bottles in the 30 and 40 cft range and so on.

It should be relatively easy to size a bottle for a specific dive parameter. The use of a rebreather for an application like this seems a bit overkill, unless there is an extenuating circumstance.

Can you share more info regarding your choice/reasoning? That may help shape the answers you're going to get.

 

[Sas]

Hello,

I'm an Industrial (aka Product) Design student from SJSU and have a few questions for the actual divers here. For my project this semester I am taking a look at redesigning a SCUBA / Rebreather unit and have a question.

Most SCUBA tanks are rated around 60 mins of use and rebreathers can go even longer.

My question is, is there a use for a device that will last you 20 minutes?
Are there scenarios where the benefit of a smaller tank would outway the time constraint? Are there situations where you really only need 20 minutes to get whatever done? Could you see this as being more useful in a military application?

Thanks,
-Dav

I cannot think of a reason why I would want a device that only allows a dive for 20mins unless it was something that say, fit in the palm of my hand and didn't require fills or a reg or something like that cos then I'd carry it in case I came across a nice bit of water I want to check out on the spur of the moment. I can get over two hours out of a single 10L steel tank on a pier dive and an hour on boat dives, it's small and not very heavy. I can get an even smaller tank if I don't want to do a dive that long too and want something lighter. There are already things such as small tanks for emergency bail out and so on, that only last for short periods of time too.

 

[vladimir]

My question is, is there a use for a device that will last you 20 minutes?
Are there scenarios where the benefit of a smaller tank would outway the time constraint? Are there situations where you really only need 20 minutes to get whatever done? Could you see this as being more useful in a military application?

Thanks,
-Dav

It depends on whether you consider MI6 military. A rebreather the size of a pen--one that could easily be concealed in the jacket pocket of a Savile Row suit--would come in handy for an operative being pursued into a shark-infested pool by gun-wielding villains bent on nuclear extortion. Twenty minutes would be plenty of time to escape, ten if he had a double-0 designation. I am sure situations like that come up all the time, and they have to be equipped for them. Of course, Q-branch had these 40 years ago, so forget about a patent.

 

[Rick Murchison]

There is definitely a diving scenario where a small light tank is preferred, and 20 minutes isn't an unreasonable run time... and that's sump diving deep within a dry cave system, simply because getting the tank to the site can be such a tremendous PITA.
But the equipment already exists in the form or 30 or 40 CF tanks...
Rick

 

[RJP]

Hello,

I'm an Industrial (aka Product) Design student from SJSU and have a few questions for the actual divers here. For my project this semester I am taking a look at redesigning a SCUBA / Rebreather unit and have a question.

Most SCUBA tanks are rated around 60 mins of use and rebreathers can go even longer.

My question is, is there a use for a device that will last you 20 minutes?
Are there scenarios where the benefit of a smaller tank would outway the time constraint? Are there situations where you really only need 20 minutes to get whatever done? Could you see this as being more useful in a military application?

Thanks,
-Dav

Definitely "designing a solution for a problem that doesn't exist."

Rebreathers already exist.

Small tanks already exist.

A rebreather that's only good for 20 min? Why bother? As the current rebreathers can be used for a short period of time if desired.

I guess the only thing that may make sense is if you could design something James Bond-like that maybe could be discretely worn under street clothes, etc for some sort of covert operation. But still sounds like a solution in search of a problem.