Air in BC? What do you do?

[AquaHump]

I am going to address the last few posts. I thinke we are talking about to difrent types of divers here. exluding walter becouse he is evry kind of diver. In the world of the single tank ya do what you can to maxamize your bottom time. this means do you checks on the boat or on shore get in and get under.
When you are talking about tech divers we do many checks. me and my buddy get in meet at 20 feet maybe do some S drills check are gear froe unwanted bubbles. make sure we are good and ready to go. In the world of tech diving we are very carfule becouse we know that at some point we are going brake the NDL and have to depend on are gear to work right. If we have a problem he have to work it out under water. that is why we do so many checks and OK's. single tank divers or rec divers dont brake the NDL so they can always do a controled ascent to the surface.
Now the term "hot drop" this is the first place I have herd that term as well. I think it is a neet buzz word, but it is the way I go in off a boat becouse there is about 12 other divers behind me waiting to get in so I am clearing the entry point. I am conrtoled with out air in my bc or my dry suit.

 

[runamonk]

Right now I always fill my BC with a few spurts because I know I'm still a little overweighted. I'm still a relatively new diver (only completed OW and AOW).

When you start your dive, your buoyancy should be slightly negative in order to maintain neutral buoyancy after you breathe some of the air out of your tank, since your tank becomes more buoyant as you consume the air.

If you are entering the water with neutral buoyancy and there is no air in your BC, you could you could find yourself ascending as your tank empties and there will be no air to release in your BC to maintain neutral buoyancy.

With that said, I would say that you need at least a little air in your BCD if you are weighted correctly.

I have a question about this because I've heard the opposite when using steel tanks. I'm still using AL80's.

 

[Walter]

I know I'm still a little overweighted.

Then get rid of the extra weight.

 

[FireDiver443]

Your entry buoyancy can and should be part of your dive plan. Your comfort with the equipment or the site, your experience and that of those you're diving with, conditions on the surface and at depth, current... heck, even if it's a boat or a shore dive... they all have an effect on how you want to enter when the DM say's "Pool's open! Dive! Dive! Dive!"

If the DM doesn't specify during the dive brief, you can always ask about the entry. Diving the plan only works when everybody does it.

Just my humble opinion.

 

[lamont]

Of course it is. Bottom time begins when a diver begins his descent.

We can argue about semantics, but 10 mins @ 10 fsw is nearly irrelevant to inert gas loading. If you limit your divetime by that 10 mins, that's not my problem...

Why aren't you in control when you enter with no air in your BC? I am.

Because you immediately drop. You are in less control than if you collect the team on the surface with everyone positive and then drop together.

He didn't call you names, he merely compared a series of what ifs to a fictional what if.

"Chicken Little" is a name. And "checking valves and ears and asking my buddys over and over if they are OK and practicing finning techniques" also read fairly insultingly.

 

[Walter]

We can argue about semantics, but 10 mins @ 10 fsw is nearly irrelevant to inert gas loading. If you limit your divetime by that 10 mins, that's not my problem...

It's the definition of bottom time.

Because you immediately drop. You are in less control than if you collect the team on the surface with everyone positive and then drop together.

I immediately drop when I want to immediately drop. When I don't want to immediately drop, I don't. That is control. How are you more in control when you kill time on the surface before dropping?

"Chicken Little" is a name.

Yes, it is a name, but it appeared to me he was using it as an analogy, not calling you Chicken Little.

And "checking valves and ears and asking my buddys over and over if they are OK and practicing finning techniques" also read fairly insultingly.

Why? It seems to be the reason most folks have said they want to enter with a full BC.

 

[lamont]

Why? It seems to be the reason most folks have said they want to enter with a full BC.

On a boat dive with a fixed upline, you can do gear matching checks on the boat, drop in, collect the team and you should be bubble checking each other on the way down (and if its an important dive you should have assembled your gear and bubble checked it in a tub the night before). Time spent on the surface can be minimized to only collecting the team together.

 

[Diverblam]

"Diverblam says she is soon off to her new dive career. She could mean that to be a clerk in a dive shop but I assumed it to mean a professional diving career. Perhaps there is a Professional Boat Dive Only career. In any case I would expect anyone seeking a diving career would desire broad experience, hence my second post; to consider yes or no does not fit all situations. Also she claims the same category of number of dives as I. The feeling I got was that she was not choosing to because it made sense but following example from desire to be like them – the dive career. So for consideration I put in my 2cents of why I make my choices. If I indicated I was giving a direct statement of what should be done, I regret it. (Such a nuisance, all these disclaimers fearing flaming.) Then she said doing so was bothering her for the reasons others spoke of."

Everyone... thank you for your advice... everyone thinks differently. But the takeaway that I got from this is that yes, it depends on your dive situation.

Redrover: Yes, I am off to pursue a professional dive career (not working in a shop) but out doing daily boat dives. In all honesty, I asked the question in the first place because I wasn't sure what made sense or what was the correct thing to do... not necessarily following procedure to be "like them", but following because I thought perhaps it wasn't necessary. As I've said... it wasn't just the DMs where were doing this but other fellow divers. So, I decided to try it and see how it works... I should have asked while I was there to get hear why they did it too...

Also, at 15 feet, I don't necessarily have difficulty in keeping neutral but I do find myself needing to kick every so often to stay down. I've not had to shoot up to the surface or struggled really hard to stay down at 15 feet. In the end tho... I will take the advice and add another pound of weight... but first... of course, try a test at being neutral on a tank with 500 psi... that was a good idea.

Also, my buddies and I are never on the surface long... no more than 30 seconds, I'd say... we usually just jump in, ask if we are ready to descend and descend... easy as pie... And if for some reason I have to wait for my buddy, depending on surface conditions, I either wait or tell them that I'll be 10 feet below waiting for them...

Lastly, yes... if it was a shore dive and depending on the conditions, then I'm sure I would act differently and perhaps put air in my bc.

Again... thank you everyone for all your advice. Everyone's still alive and here, so even though it may not work for others, it worked for each individual. =)

 

[Web Monkey]

Instructors usually teach their OW students to put air in their BCs so they can get their too large class together and descend as a group. That is the ONLY purpose the practice serves. I teach only small classes and teach my students not to inflate their BCs prior to entry.

While a hot entry may be great for experienced divers in high-current areas who are 100% certain of their pre-dive check, it's not appropriate for all divers or dive sites.

A lot of new divers forget to check one or more important items and don't have great buddies. Starting out buoyant on the surface may be the difference between being embarassed and being in serious trouble.

A diver who is buoyant and accidentally descends with their air off just needs to fin a foot or two back to the surface for a little quick oral inflation and some assistance. If the same happens overweighted, at 20' on the way down, it's going to be a significant problem.

The same goes for descending on a on a snorkle instead of a reg (don't want to start a debate, OWD are typically taught to have a snorkle). Doing this near the surface with air still in the BC is embarassing. Doing it while dropping like a stone is a problem, unless the diver can quickly find a second stage.

I've certainly done my share of "Darwin Award" tests, as has everybody else here, and while it's great to say that divers shouldn't be overweighted, should do effective pre-dive checks, should have great buddies and all the rest, the reality is that new divers do dumb things, and being on or near the surface gives an extra safety margin and a second chance to fix things.


Terry

 

[Sideband]

I have been on several boats where we were told NOT to surface and NOT to bother with giving an 'OK'. When you have 3+ foot seas and a current they don't want you on the surface any longer than necessary. I have had this said in Pompano and out on Lake Michigan.

Joe