RAID Cave 1 - Good Course?

[rjack321]

Why is sidemounting in situations where restriction is not the primary consideration so broadly disdained? If someone is more comfortable in the sidemount setup, and it is being done properly, why is it wrong?

In event of a reg failure you immediately lose access to half of your gas. Manifolded doubles still allow you to access all your gas. While its true that you can't (in theory) go completely OOA in sidemount. Reg failures are far more common and likely than OOA events.

SM is also an epic PITA on a pitching rolling boat. And its not "easier on your back" when you have all the same gear on to stand up and waddle over to the transom or try to climb a boat ladder anyway. It also wastes the perfectly good place to put stuff, on your back, like a backpack. Once you have 2 deco gasses your cross-sectional area is just as wide as backmount anyway. Plus almost everything about SM is custom fitted and "worn" by the diver. Sharing gear/tanks when you have a failure or you are contributing tanks/gear to a big project you end up adjusting stuff for each individual which takes up time and energy and often ends up being suboptimal.

I backmount, I sidemount, I backmount CCR and I sidemount a CCR. Picking the right tool for the job is paramount.

 

[wetb4igetinthewater]

In event of a reg failure you immediately lose access to half of your gas. Manifolded doubles still allow you to access all your gas. While its true that you can't (in theory) go completely OOA in sidemount. Reg failures are far more common and likely than OOA events..

Are we talking about regs failing shut here?

 

[rjack321]

Are we talking about regs failing shut here?

Failing shut is rare but can happen
Or blowing 1/2 water 1/2 air
Or the DIN to body connection failing
Or a LP hose splitting and not having the option of feathering
2nd stage body cracking in half
etc etc

 

[wetb4igetinthewater]

Failing shut is rare but can happen

Quite rare. Happened to an acquaintance once.

Or blowing 1/2 water 1/2 air

Excuse the possibly stupid question, but what does that mean?

Or the DIN to body connection failing

Has that happened during the course of a dive?

Or a LP hose splitting and not having the option of feathering

Why would feathering not be an option?

2nd stage body cracking in half
etc etc

Never thought of that one, but I'm not cave trained.

 

[cerich]

In event of a reg failure you immediately lose access to half of your gas. Manifolded doubles still allow you to access all your gas. While its true that you can't (in theory) go completely OOA in sidemount. Reg failures are far more common and likely than OOA events.

SM is also an epic PITA on a pitching rolling boat. And its not "easier on your back" when you have all the same gear on to stand up and waddle over to the transom or try to climb a boat ladder anyway. It also wastes the perfectly good place to put stuff, on your back, like a backpack. Once you have 2 deco gasses your cross-sectional area is just as wide as backmount anyway. Plus almost everything about SM is custom fitted and "worn" by the diver. Sharing gear/tanks when you have a failure or you are contributing tanks/gear to a big project you end up adjusting stuff for each individual which takes up time and energy and often ends up being suboptimal.

I backmount, I sidemount, I backmount CCR and I sidemount a CCR. Picking the right tool for the job is paramount.

you can feather or even switch regs in sm, you absolutely don't "lose all your gas" in a reg failure.

SM is easier on a pitching boat than doubles if you know how.

I find it is much easier on my back, on land and in water.

Agree, it isn't about resistance

Sharing gas for the majority of sidemounters is just passing the long hose, same as backmount. Some are still stuck on handing off cylinders and there really is no need imho.

 

[rjack321]

Excuse the possibly stupid question, but what does that mean?

remove the exhaust diaphragm from a 2nd stage and try to use it

Has that happened during the course of a dive?

Right here his DIN to body fitting has failed.
Calm-headed response
Chances are good that the reason he's on the guest's octo is because when this oring fails the gas rushing past creates a venturi effect that sucks water in and the 2nd stage delivers a watery/air mix.​

Why would feathering not be an option?

A split LP hose will not deliver gas to the 2nd stage worth a damn
And it will drain the tank in about 1-3mins depending on depth.

 

[rjack321]

you can feather or even switch regs in sm, you absolutely don't "lose all your gas" in a reg failure..

Some you can, but you cant feather your way out of every type of reg failure.

 

[rjack321]

I'm not against SM, I use it and even encourage it sometimes. I encourage beginning cave and tech divers to take at least cave1 (cavern & intro or similar) in BM because 1) it works and 2) in many cases it is the right tool for the job so being capable and competent in this basic configuration is worthwhile. I have actually been cave diving with an experienced, accomplished, full cave explorer who confided in me that they had "no idea" how a manifold worked. That wasn't very inspiring.

I am against the mindset that SM is ideal no matter what. Which is just weird to me. I don't know anyone who ever said BM is ideal everywhere at anytime because its just so amazing. (or CCR for that matter).

 

[cerich]

Some you can, but you cant feather your way out of every type of reg failure.

I also said even switch. Any additional failure points in SM are matched by failure points with an isolator in doubles. In fact IMHO, isolated doubles have proven to be more problematic than what it is supposed to do for safety.

 

[wetb4igetinthewater]

I am against the mindset that SM is ideal no matter what. Which is just weird to me. I don't know anyone who ever said BM is ideal everywhere at anytime because its just so amazing. (or CCR for that matter).

I so much prefer taking bottles up and down the slopes on Cove 2 separately (sorry people, but Richard knows what I'm talking about as that is a dive site local to both of us).

Downsides, I need a head start to kit up in the water before my backmounted buddies.

Right here his DIN to body fitting has failed.
Calm-headed response
Chances are good that the reason he's on the guest's octo is because when this oring fails the gas rushing past creates a venture effect that sucks water in and the 2nd stage delivers a watery/air mix.​

I suspect that problem existed as soon as he hit the water. Probably didn't realize it was leaking as he kitted up.