What do you look for in students to tell if they are ready for AN/DP?

[Wibble]

For the sake of decorum, we’ll have to agree to disagree.

BTW how do you inflate a SMB on CCR? Oh, that’s why some CCRs have a longhose

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You obviously mean a crack bottle or CO2 inflated SMB

Shirley you’re not suggesting you bailout to put up a bag!

 

[kierentec]

You obviously mean a crack bottle or CO2 inflated SMB

Shirley you’re not suggesting you bailout to put up a bag!

No, nobody said actually bailout. You just exhale into the bag, then go back onto the loop. Just the same as on OC, except you can actually take an even bigger breath since it’s all coming from the counterlungs and just being transferred to the bag, zero buoyancy shift. You let the bag go as you either a) take a breath off the bov and open the loop, or b) open the loop and activate the ADV or dil mav.

 

[rddvet]

I’m shocked people find it difficult to inflate a bag on ccr. I thought that was a very basic requirement of any ccr class. There’s several ways to do it all of which are easy

 

[Jack Hammer]

No, nobody said actually bailout. You just exhale into the bag, then go back onto the loop. Just the same as on OC, except you can actually take an even bigger breath since it’s all coming from the counterlungs and just being transferred to the bag, zero buoyancy shift. You let the bag go as you either a) take a breath off the bov and open the loop, or b) open the loop and activate the ADV or dil mav.

I thought would be super hard to do until I actually did it. In realty it is very quick and simple.

 

[Ayisha]

Frozen lips won’t seal around the spigot.

No, but the inner rim of your thumb/index finger of your dry glove do. And your lips seal against your dry glove

No issues getting plenty of gas in a 2m smb by exhaling into it. Lots of issues and hazards associated with creating a rocket that’s attached to you by a piece of string….

The gloves work. Also, if you place the oral inflation tube in the corner of your mouth rather than pursing your frozen lips around it, the gas goes in well. It sounds weird, but it works.

 

[Wibble]

No, nobody said actually bailout. You just exhale into the bag, then go back onto the loop. Just the same as on OC, except you can actually take an even bigger breath since it’s all coming from the counterlungs and just being transferred to the bag, zero buoyancy shift. You let the bag go as you either a) take a breath off the bov and open the loop, or b) open the loop and activate the ADV or dil mav.

Utter nonsense.

 

[Wibble]

I’m shocked people find it difficult to inflate a bag on ccr. I thought that was a very basic requirement of any ccr class. There’s several ways to do it all of which are easy

There’s nothing difficult about inflating a SMB. You use a drysuit hose from the bailout, from your drysuit, even the deco gas. Or you use a bailout regulator if it's open-bottomed. But most people use some form of crack bottle/CO2 cannister as it's much easier.

I know of nobody and I mean nobody, who dives in the sea who orally inflates a SMB bag. This is some form of instructor taskloading skills nonsense on a training bag in a quarry.

Come off the loop to orally inflate it…. Not only pointless but adding considerable risk. How do you clear the mouthpiece if you’ve no breath left?

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For the benefit of non CCR/rebreather divers...
The breathing loop on a rebreather must be kept dry. The mouthpiece, known as a Dive Surface Valve (DSV), is closed by a lever before it is removed otherwise water will flood into the loop. When returning to the loop, the mouthpiece is put into the mouth and you blow as the DSV is opened which blows the water from the mouthpiece and your mouth out through the lever/valve mechanism as it is being closed; this 'hole' which the water and breath escapes is fully sealed when the DSV lever is fully open or closed.

Thus you need some breath left when returning to the loop otherwise some liquid will enter the Closed Circuit. Unlike an open circuit regulator there is no concept of a purge button — unless you have a Bailout Valve (BOV), which the vast majority of rebreather divers do not have installed (maybe 10% use one, no references, just empirical observation).

Cue row over different rebreather designs…

 

[kensuf]

Well I am stealing this idea.

I assume you just measure total length and do the needed math half for 33ft, third for 66ft?

Yup.

 

[kensuf]

For deeper SMB fills (open/duck-valve bottom), I like to hold onto the bag and fill from my wing (corrugated hose). Net buoyancy change is 0 until I let go of the bag so I can take my time to be sure everything is tidy and clear before releasing, then a good shot on the inflator to get just slightly negative since I'm going up anyway and would soon have to be dumping.

I was introduced to this method a few months ago along with holding the SMB/Reel during ascent until you're about 10' below your first stop before slowly paying the reel out while finishing that last 10' to the first stop. I've only used this a couple of times in playing around with it. While it's a pretty slick way to have a very smooth ascent, you need to manage your buoyancy correctly while also holding onto the reel spindle - I can see the opportunity for user error related problems.

 

[rddvet]

There’s nothing difficult about inflating a SMB. You use a drysuit hose from the bailout, from your drysuit, even the deco gas. Or you use a bailout regulator if it's open-bottomed. But most people use some form of crack bottle/CO2 cannister as it's much easier.

I know of nobody and I mean nobody, who dives in the sea who orally inflates a SMB bag. This is some form of instructor taskloading skills nonsense on a training bag in a quarry.

Come off the loop to orally inflate it…. Not only pointless but adding considerable risk. How do you clear the mouthpiece if you’ve no breath left?

---

For the benefit of non CCR/rebreather divers...
The breathing loop on a rebreather must be kept dry. The mouthpiece, known as a Dive Surface Valve (DSV), is closed by a lever before it is removed otherwise water will flood into the loop. When returning to the loop, the mouthpiece is put into the mouth and you blow as the DSV is opened which blows the water from the mouthpiece and your mouth out through the lever/valve mechanism as it is being closed; this 'hole' which the water and breath escapes is fully sealed when the DSV lever is fully open or closed.

Thus you need some breath left when returning to the loop otherwise some liquid will enter the Closed Circuit. Unlike an open circuit regulator there is no concept of a purge button — unless you have a Bailout Valve (BOV), which the vast majority of rebreather divers do not have installed (maybe 10% use one, no references, just empirical observation).

Cue row over different rebreather designs…

Maybe things are different in the UK. Everyone I know personally was required to shoot an smb in ccr class using a closed bag orally inflated. It really is not hard at all, it’s not risky or dangerous. The idea that’s it’s dangerous to orally inflate a bag on ccr is puzzling to me. As has been stated by several people it isn’t hard.
To your point of having enough breath to clear the loop: take a breath from the bov or your bailout. Or even better, be intelligent enough to not use every single last ounce of breath you have. In a lot of your posts you really seem to think the most basic things are dangerous, hard to do, or risky.