Low on air done right?

[IceBergSlim]

And you also failed to check his gauge, knowing that he would run OOA before you did.

Is it common for you to have others check your gauge?

 

[japan-diver]

Although the situation was far from perfect it wasn't as bad as some are making it. Obviously your calculation of turn pressure was a bit off or there was some reason why your buddies air comsumption went up on the way back. Many times it is easier to swim on the bottom then the surface so if you have the air to safely extend the swim back underwater this is usually the right choice- it sounds like you had plenty of air to extend the swim back safely and left air in the buddies tank to use for ascent and BC inflation once on the surface - this is some of the good things you did. You also talked about the possibility of sharing air before the dive so another good thing. So you implemented a plan that was discussed before the dive to deal with being low on air again good planning and execution for that point.

Proper gas management/planning and ensuring that all your buddies monitor their air and communicate the fact to the rest of the team are some things that need to be improved.

 

[nereas]

Is it common for you to have others check your gauge?

It is common for me to check my buddy's SPG, normally half way though the dive.

All the major training agencies teach that.

 

[nereas]

Wow, that was harsh.

...

Were you expecting an atta-boy for scaring this novice witless and nearly getting him drowned? What kind of buddy does that make you?

 

[crispix]

Were you expecting an atta-boy

What happened to the good ol' scubaboard YOU'RE GONNA DIE retort? That's what I expected!

You did get a PADI bash in there, at least. All that's missing is a zinger about pony bottles, please.

 

[Scuba-Stu]

Was on a dive with my regular buddy and a new guy last week. The new guy was a less experienced diver, and we knew going into it that he was going to be an air hog. Newbie had an AL80. Regular buddy and I both use a larger tanks plus ponies.

We picked a conservative profile, max depth 50ft, and what we thought was a good turn pressure for the newbie. He hit his turn pressure even earlier than we anticipated. On the way back in (long bottom swim back to shore), newbie was getting too low on air. (We had discussed this possibility before the dive -- didn't think it would actually happen.) So he took my buddy's regulator and they swam back in sharing air until we were at 20fsw. Newbie went back to his own reg.

A few minutes later, he held up his gauge with big eyes and was at about 200psi. I instantly gave a big thumbs up, and we did a safe ascent from less than 15fsw. He had enough air to inflate his BC at the surface and all was fine.

I consider this a successful failure. No one deployed a pony bottle (all contigencies are planned as if we did not have the pony tanks.)

So, some lessons learned, any thoughts?

Can I ask why didn't you give him the pony bottle?

 

[charlesml3]

Were you expecting an atta-boy for scaring this novice witless and nearly getting him killed?

Dude, you're clearly just trying to start a flame war. If you don't have anything other than this nonsense to contribute, then please just go away.

At no point was the novice "scared witless" and you can't even be serious about the "nearly getting him killed" part.


Honestly, I really can't see anything the OP did wrong. They knew he was going to go through his gas quickly and planned accordingly. They planned their dive and dove their plan. Sure the new guy got a little wide-eyed when his guage hit 200 psi but it was far from an emergency.

-Charles

 

[Ber Rabbit]

Was on a dive with my regular buddy and a new guy last week. The new guy was a less experienced diver, and we knew going into it that he was going to be an air hog. Newbie had an AL80. Regular buddy and I both use a larger tanks plus ponies.

We picked a conservative profile, max depth 50ft, and what we thought was a good turn pressure for the newbie. He hit his turn pressure even earlier than we anticipated. On the way back in (long bottom swim back to shore), newbie was getting too low on air. (We had discussed this possibility before the dive -- didn't think it would actually happen.) So he took my buddy's regulator and they swam back in sharing air until we were at 20fsw. Newbie went back to his own reg.

A few minutes later, he held up his gauge with big eyes and was at about 200psi. I instantly gave a big thumbs up, and we did a safe ascent from less than 15fsw. He had enough air to inflate his BC at the surface and all was fine.

I consider this a successful failure. No one deployed a pony bottle (all contigencies are planned as if we did not have the pony tanks.)

So, some lessons learned, any thoughts?

Personally I don't consider 50 feet a conservative profile with a newbie air hog diver for the first dive I do with them. I did a dive with one air hog I knew well and had several dives with, depth was 60 feet and we were both on AL80's. I don't remember the run time (maybe 25 minutes?) but I had used 700psi and he had used 2300psi.

I keep my plans to no deeper than 35 feet and stay fairly close to the entry/exit point when I dive for the first time with a newer diver. Basically that first dive conforms to my OW check out dive protocol for my safety and to help boost their confidence.

What was the turn pressure you picked?

I've noticed that last 1400psi or so goes REALLY fast. I make sure I'm within a hundred feet or so of my exit and approaching safety stop depth by the time they reach 1000 pounds. Once it starts dipping under that number some newer divers start getting concerned especially if they are not familiar with the area. That makes their SAC go up and makes the air go away faster making them more concerned...you get the picture.

BTW, my husband has a gauge that reads 300psi when it's not attached to anything...the manufacturer said that's within the acceptable 10% accuracy range
Ber :lilbunny:

 

[crispix]

Can I ask why didn't you give him the pony bottle?

Two reasons: First, sharing the way we did was part of the dive plan. (Yes, I will change the plan next time, but that's what we did.) Pony is not part of the plan, but that's a whole other can of worms on this board.

Second, we had another dive planned (without the newbie) afterwards, and it's nice to keep a full pony available for the second dive.

Anyway, I appreciate all the comments, especially the logical posts from the instructors and the thoughts about where and how to dive with a new diver. This was not a "near miss", but rather an opportunity to improve. I got what I needed, thank you.

I think it's time to let this thread die. I love a good flame war as much as the next guy, but it's too much energy.

 

[crispix]

I did a dive with one air hog I knew well and had several dives with, depth was 60 feet and we were both on AL80's. I don't remember the run time (maybe 25 minutes?) but I had used 700psi and he had used 2300psi.
[...]
I've noticed that last 1400psi or so goes REALLY fast.

You pretty much nailed what happened. We picked a turn of 1400 (and turned on the dot at 1400), and he went down to 700 in no time flat heading back in; that's when he started sharing with the other buddy. And after going back to his regulator he went from 700 to 200 in a few minutes in shallow water. I'd have to do the math, but he had to be well over 1.5cf/min sac.

Anyway, I'm breaking my own suggestion to let the thread die. I'll keep lurking, but I'm really going to stop now. Thanks again!