Z Planer

Mephisto26

Hey everybody...

A friend of mine is using the Zplaner and asked me if I know what "sld" stands for...it's supposed to be next to the setpoint field...

Unfortunetly I only use the Vplaner and have no idea soooooo.....I need your help guys...

Thanks in advance...

Patrick

Gobfish1

SCAMAHORN SLIDES

The Scamahorn Slide was named by Leon Scamahorn, and is basically
a way to use Dalton's Law to your deco advantage when diving
with a Closed Circuit Rebreather. When you descend quickly on
a CCR, your PO2 can tend to run above your setpoint by the time
you hit the bottom, unless you do some manual intervention. It
will take awhile to breathe down the O2 until you are back at
the setpoint, which sometimes works to your deco advantage. With a
Scamahorn Slide, you intentionally let your PO2 spike on descent,
then ride the deco advantage until your PO2 "slides" back
to your setpoint.

Let's say your setpoint is 1.2, and you allow the PO2 to creep up
to 1.6 on descent. Once on the bottom, it will probably
take you about eight minutes of breathing to get your setpoint
back down to 1.2. On a deep dive with 15 or 20 minutes of bottom
time, this "sliding" PO2 will save you some deco obligation,
if you can account for it in dive planning. And since you're only
talking about maybe six or eight minutes of elevated PO2, it won't
have too much negative impact on your CNS clock.

So in the program, if you want to do a Scamahorn Slide for
the above example, you'd set the amount of time it takes you
to breathe down .1 PO2 at depth, then instead of making your
setpoint at the bottom "1.2", specify it as "1.2-1.6".

ps this is form zplan

__________________
Steve G

Apparently not the only gay diver in the village

http://drinkingliberally.org/blogs/o...nzee-glock.gif

http://www.scubatunes.com/audio/vol01/mp3/HiTech.mp3

zepp

I was going to say the same

__________________
I'm not a bad person.....HONEST
my homebuild photos http://www.rebreatherworld.com/photo...ery.php/cat/48
CLASSIC KISS #052

Mephisto26

Thanks guys...

dive2dive2000

Just curious, How much deco will it save you from a dive to 180' 40 min BT diving a 1.2 with a 10/50 dil? Thanks in advance

__________________
Safe Diving,
Martin

Dave Sutton

It can be substantial, but it all depends on how high you let the PP02 go on descent, which is a function of:


(1): What starting PP02 on the surface you select,

and

(2): also MOSTLY of the the diluent selected.


Use of a higher F02 diluent will raise the slide higher and for any given descent from surface. Within whatever PP02 limits you select as desirable, the more 02 in the dil the hotter you bottom out and the more deco advantage you obtain as it takes longer to slide from PP02 (bottoming) to PP02 (setpoint). *Some* of us bottom out as high as 2.0 PP02 and then let the PP02 slide down to setpoint of 1.4, which may take up to a third of our planned bottom time. There is substantial advantage at that point from a deco standpoint.

10% for a 180 foot dive? In my opinion, to be polite, is that this gas is *not optimal*. That depth gives 20% mix a 1.3 PP02, meaning that it's an ideal diluent for that depth. Start your loop at about 0.4 at the surface, hit the bottom at about 1.6, burn it down to 1.2 after about 10 minutes and you'll not only save some deco but also have viable SCC mix and some OC capability... For me? I'd personally start my loop at about 0.6 at the surface, hit the bottom at 2.0, and burn down to setpoint after perhaps 15 minutes. I'm going to have substantially lower inert gas loading and will be way within PP02 exposure limits.


Oh, wait.... we talked about this diluent selection thing before. The deco slide we are talking abut here is a part and parcel of that debate too.

Not to mention all of the *other* advantages of not using a hypoxic dil when not needed.....


Dave

__________________
"Changes in Lattitudes, Changes in Attitudes, Nothing remains quite the same".... www.nobubblediving.com