Mounting tanks upside down

[Uncle Pug]

I would agree on all your points except this one. The bottoms of the tanks being flat is not ideal but that could easily be changed.

So in other words you agree with me that the way presented isn't streamlined but figure that it could be changed so as to be more streamlined so you disagree with me?

OK... I'll add another major point to make up for it.

5) the ends of the tanks (especially if the boots are removed to make the rig more streamlined) are an excellent line trapping device. Without the crossover between them and without the regulator hoses protecting the space between the divers back and the tanks this whole area is very vunerable. A diver who lacked the mobility to dive his rig right side up certainly would lack the ability to reach back and untangle himself.

 

[Scott M]

5) the ends of the tanks (especially if the boots are removed to make the rig more streamlined) are an excellent line trapping device. Without the crossover between them and without the regulator hoses protecting the space between the divers back and the tanks this whole area is very vunerable. An a diver who lacked the mobility to dive his rig right side up certainly would lack the ability to reach back and untangle himself.

I'm still having a little trouble seeing it.

Lets take a typical entanglement (if there is such a thing) say a low hanging elec. cable wraps around both rigs.

With the upside down tanks it would just be wrapped around a smooth large object (or two as the case may be) simply stopping and backing up or dropping slightly would seem to me to be a very easy entanglement to get out of or it would seem to be quite easy for your buddy to manuever you in a way to slide you out of it.

With the standard set-up, that same cable now wraps around the manifold and valves. It would now seem the entanglement is going to require a fair amount more work to get out of. Simply backing up or dropping will no longer work as the cable is wrapped around something with edges.

Am I wrong here?

 

[Uncle Pug]

One thing you *cannot* argue is that it's easier to reach to valves.

Have you ever used inverted twins yourself? Were you able to reach the isolator valve?

 

[Scott M]

One more quick thought.

Now lets put the same diver in a wreck with lots of sharp edges. For whatever reason (tight swim through, upwelling etc) the diver finds themselves brushing the overhead metal which happens to be sharp. (Not really that far fetched) wouldn't the upside tanks keep the hoses from possibly getting cut. It would seem to me the tanks themselves could handle the sharp edge much better then hoses, valves manifolds which could break or be cut much easier.

 

[Scott M]

Have you ever used inverted twins yourself? Were you able to reach the isolator valve?

No, just doing some cyber diving. I was recently cyber-cave-certified so I was working on my cyber gear and technique.

Actual when I see things like that I like to think them through.

Edit: Whoops thought you were talking to me. my bad.

 

[Uncle Pug]

I'm still having a little trouble seeing it.

I suppose that if you realized soon enough that you had snagged a line you could just back up like you say.

Also I suppose you be very careful never to allow something solid like a railing or other projection get jammed in between the tanks.

 

[Scott M]

I suppose that if you realized soon enough that you had snagged a line you could just back up like you say.

Also I suppose you be very careful never to allow something solid like a railing or other projection get jammed in between the tanks.

Agreed, caution is always advisable.

When I saw the thread for some reason the image of that guy that died on the Andria Doria after being entangled popped into my head so I was thinking it through.

 

[MikeFerrara]

A nice, easy to read article one guys reasons for using an inverted twinset who actually *dives* an inverted rig, as opposed to making fun of one on the internet.

http://www.nigelhewitt.co.uk/diving/rig.html

One thing you *cannot* argue is that it's easier to reach to valves. (but Im sure someone will try)

I guess you guys also used to make fun of commercial/military divers 15+ years ago for breathing gases other than air.

Well, put a big old canister light on that divers right side and a couple stages hanging off his left and see how easy he can reach his valves.

I doubt that you could get to the isolator at all.

 

[MikeFerrara]

I would agree on all your points except this one. The bottoms of the tanks being flat is not ideal but that could easily be changed.

The hose routing "appears" to be much more streamlined. Down low and out of the way of any entanglement hazard unlike the typical arrangement most use with all the hoses run off the top the hoses are exposed to hazards much more than this set-up appears to be. I may be wrong but it looks OK to me.

the hose routing looks like a mess.

With normal hose routing they go in and down streight to where they need to be and are very protected.

my backup reg hose is short and only has to reach around and sit under my chin. I can't even picture how it could rout comming from below. The same for the wing inflator hose.

 

[Uncle Pug]

Edit: Whoops thought you were talking to me. my bad.

what I say to one cyber diver I say to all.