configuration of gear

[mania]

OK, I have some questions to more expierienced DIR guys.

First - the hypothetical situation but as I understand acceptable by the DIR standarts.

I'm diving wet suit with one tank, two valves. So - on my right valve I have a primary 1st stage, left valve - back up 1st stage.
On the primary I have my primary 2nd stage and wing inflator. On the back up I have back up 2nd stage and manometer.
As I understand this is the proper configuration.
Now imagine that I have a failure of the primary 1st stage. OK, I close my right valve and switch to the back up regulator. But in this case I'm left with no possibility of inflating the wing (except the oral way which is not very efficient and quick). Wouldn't it be better to have the inflator hose on my back up 1st stage instead of the primary? Esspecialy that primary has to do heavier work - both regulator and the wing, which may lead to freezing in cold water. (yeah I do dive the wet suit in the cold water).
So I would like to know your opinion on my dillema - why the only buoyancy device is on the primary 1st stage?
OK I know that in case of the inflator failure I would not be able to close the left valve and at the same time dump air from my wing. But the descripted above situation makes me wonder why it's as it is?
Mania

 

[IslandHopper]

I'm not sure it really matters. Once you've got a failure, you're gonna call the dive and you won't have to orally inflate much (if at all) ... because you'll be ascending and therefor only need to vent gas.
Even so, if you had the inflator on the left regulator, that one could fail just as easilly, and you'd still have to orally inflate.
Assuming you keep yourself neutral throughout the dive, inflating or venting your wing isn't gonna be needed until after you secure the reg/valve dilema anyhow.

Now, feel free to show me where I'm wrong.

 

[Reinoud]

OK, I have some questions to more expierienced DIR guys.

First - the hypothetical situation but as I understand acceptable by the DIR standarts.

I'm diving wet suit with one tank, two valves. So - on my right valve I have a primary 1st stage, left valve - back up 1st stage.
On the primary I have my primary 2nd stage and wing inflator. On the back up I have back up 2nd stage and manometer.
As I understand this is the proper configuration.
Now imagine that I have a failure of the primary 1st stage. OK, I close my right valve and switch to the back up regulator. But in this case I'm left with no possibility of inflating the wing (except the oral way which is not very efficient and quick). Wouldn't it be better to have the inflator hose on my back up 1st stage instead of the primary? Esspecialy that primary has to do heavier work - both regulator and the wing, which may lead to freezing in cold water. (yeah I do dive the wet suit in the cold water).
So I would like to know your opinion on my dillema - why the only buoyancy device is on the primary 1st stage?
OK I know that in case of the inflator failure I would not be able to close the left valve and at the same time dump air from my wing. But the descripted above situation makes me wonder why it's as it is?
Mania

two things:
normally with such a problem you would end your dive. Normally, you would be trimmed correct at every moment during your dive. So when you end your dive it is not needed to inflate since you only have to ascend.

On complexer dives you will have backup buoancy. (Normally a drysuit). This is inflated either from the left post or from a separate argon bottle.

 

[mania]

OK I know that with such failure I have to end the dive. What if I have any - even a small one - deco?
OK - as simple as that - it's Red Sea - so wet suit. Deep dive but not very long, so let's say I have to have all together app. 10 minutes of deco. So I can't call the dive - got to stay.
And then what?
Mania

 

[Soggy]

OK I know that with such failure I have to end the dive. What if I have any - even a small one - deco?
OK - as simple as that - it's Red Sea - so wet suit. Deep dive but not very long, so let's say I have to have all together app. 10 minutes of deco. So I can't call the dive - got to stay.
And then what?
Mania

You are still ascending and thus don't need to inflate your wing.

 

[vlada]

OK I know that with such failure I have to end the dive. What if I have any - even a small one - deco?
OK - as simple as that - it's Red Sea - so wet suit. Deep dive but not very long, so let's say I have to have all together app. 10 minutes of deco. So I can't call the dive - got to stay.
And then what?
Mania

Then inflate the wing manualy - if you are weighted properly, should not take more then 2-3 breaths

 

[Soggy]

Incidentally, you wouldn't be doing deco on a single tank and you won't see many DIR divers below 100' without doubles.

 

[mania]

Soggy - that much I know and as I stated at the beggining it's hepothetical question. I'm simply trying to understand why some things are done in this and not the other way. But on the other hand - you will find them in Egypt going on single tank deeper than 100 ft.
Mania

 

[jonnythan]

One of the reasons to have the inflator on the right post is that if you donate your primary and you're on your backup, you still have two available breathing sources from independent posts on you - your backup reg and your inflator. Say your buddy has your long hose and you're on your backup.. your left post blows up [or rolls off in a cave or wreck, or whatever], in a pinch you can get a couple of breaths off the inflator, which is on the other post.

 

[Soggy]

In addition to what Jonythan said, another big part of the concept is that, as you go from configuration to configuration, you don't change where your hoses are routed, where gear is, etc. This allows you to progress without having to unlearn anything and maximizes your efficiency during an emergency. If my wing is *always* being inflated off the right post, I know that, regardless of whether I'm in a wetsuit or drysuit, when I shut down that right post, my wing can no longer be inflated off of back gas.

Let's be honest....not having access to your power inflator is a minor failure and orally inflating your wing for a few minutes shouldn't be that big of an issue. I've done dives where I didn't have it hooked up for 20 minutes or so because I disconnected it due to a malfunctioning inflator.