Problem at Gilboa 4/21

[wb416]

You guys are terrible!!

M_Bipartitus: PM sent

 

[pickens_46929]

Good point Bob. You can't practice enough.

I think this pretty much sums it up... practice, practice, practice.

 

[Belmont]

What about pinching your regulator hose in case of freeflow. Could it help reduce the air loss while letting you sip air going up on a controled normal ascent?
Assuming your octo is busy with your buddy.
Maybe a stupid question, excuse me...

 

[spectrum]

M_Bipartitus I assume that you meant as follows (see bold stuff)

I've noticed you have given a number of posts related to this and I would like to learn some from you. I am a relatively new diver (<50 dives) who typicaly carries a pony. I have it at my side like a stage, but I have the pony second stage on a bungee around my neck. I am used to donating the primary and switching to the pony at the same time. I don't have any plans to get doubles and/or take a deco procedures class, so any advice about what specific procedures should be practiced would be helpful, and relivent as I will be doing more colder diving in the near future, including Gilboa next week (though nothing deep.)

Are you saying that you don't have an alternate second stage (octopus) on your primary air supply? I would add an alternate second for sure. It's a shame to have that large air reserve accessible to only one diver short of classic buddy breathing. Since teaching the skill has fallen out of favor it really does not count as a contingency.

Since you typically (not always) dive with the pony having the octopus is essential.

By keeping the pony second bungeed to the bottle the entire air source can be handed off if needed.

Having a plan and practicing it is great.

Be sure to communicate your air share plan to your buddy. If it's a frequient buddy drill on it.

Pete

 

[fisherdvm]

What about pinching your regulator hose in case of freeflow. Could it help reduce the air loss while letting you sip air going up on a controled normal ascent?
Assuming your octo is busy with your buddy.
Maybe a stupid question, excuse me...

Try pinching your hose once when breathing off from it. Can you still breath?? They are too rigid, and the pressure in those LP hoses can approach 3000 psi or tank pressure if it is free flowing from the first stage.

I believe that first stages are built to err on the side of free flowing, thus always assuring air supply to the diver. Unfortunately, that can drain the tank pretty quick.

 

[spectrum]

What about pinching your regulator hose in case of freeflow. Could it help reduce the air loss while letting you sip air going up on a controled normal ascent?
Assuming your octo is busy with your buddy.
Maybe a stupid question, excuse me...

Nothing stupid about brainstorming save your skin ideas! This sort of visualization is some of the best training you can give yourself IMO.

Since the buddy is apparently doing OK on the alternate we can assume that the first stage is delivering good intermediate pressure. In that case I don't see why you could not try to feather the primary by kinking the hose.

Keep in mind that if both are free flowing it is a fair sign that the first stage is stuck and delivering run-away intermediate pressure. Kinking one hose could slow the loss. Kinking both could result in a rupture. Sooner or latter it becomes your hose or your life. The important thing to remember is not to waste time fussing with parlor tricks, start your exit and make the most of what you have.

Pete

 

[fisherdvm]

Wow, I've learned more about deep diving from this post than I ever did before.

So many factors involved in cold water deep dives, that are less likely to occur on warm water deep dives - increased air flow from your drysuit inflation, buddy breathing off your octo, colder water temperature, bouyancy control problem with drysuit and BC, free flowing - not only from your reg, but your buddy's reg if you were to use their octo..... etc. etc..

It seems to me the logical thing to do if your reg free flowed in cold water, the more sane thing to do is simply breath off the reg and head for the surface.

Why risk freezing your buddy's reg and causing his to free flow also while your tank go dry??

Does my logic make sense, go with your training, breath off your free flowing reg, and head for the surface.

Rather than risk a double tragedy by counting on your buddy's back up reg... Better yet, no point of diving deep in cold water without a pony...

 

[DandyDon]

What about pinching your regulator hose in case of freeflow. Could it help reduce the air loss while letting you sip air going up on a controled normal ascent?

I read something here somewhere about that. I'll see if I can find it - or maybe someone still on the thread knows...?

Edit: See this thread http://www.scubaboard.com/showthread.php?t=187403

Assuming your octo is busy with your buddy.
Maybe a stupid question, excuse me...

I think the problem was with the First stage free flowing, therefore having a buddy on your alternate second stage would add to the problem.

 

[wb416]

Rather than risk a double tragedy by counting on your buddy's back up reg... Better yet, no point of diving deep in cold water without a pony...

But you're back to thinking you can get your pony deployed in a chaotic shower of bubbles. Is this something you work on?

A good reality check might be to have you're buddy unexpectedly shut off your backgas and see how quickly you can get to the pony reg. The time to find out if you can do or not is in 20ft of water, not 100ft of water.

 

[Dan Gibson]

Actually, not true. The LP hose is not too rigid and you can pinch a hose and stop the flow. It was demonstrated to us in my cave class when someone accidentally had a kinked long hose during a lights out/OOA. We got a prety good *** chewing after the dive. Now, if in the midst of a freeflow, it's just going to blow out the other second stage if you try and stop the flow this way on one of the hoses.

I don't know what the actual burst pressure is for the LP hoses (they are rated at 250 psi IIRC), but I would doubt it's anywhere near 3000 psi. I would think the pressure in the hose should never exceed the hose burst pressure since you are limited by the orifice size between the HP and IP side of the first stage. Pressure should rise until the hose blows.

Try pinching your hose once when breathing off from it. Can you still breath?? They are too rigid, and the pressure in those LP hoses can approach 3000 psi or tank pressure if it is free flowing from the first stage.

I believe that first stages are built to err on the side of free flowing, thus always assuring air supply to the diver. Unfortunately, that can drain the tank pretty quick.