decompression without training

[FishOutUvH2O]

I wanted to know if it was a common practice... and the risks involved

Like others have said, I can only speak to the limited snapshot of the diving world I have, but, no, it's not common for people to have their computers go in to deco-mode and "punish" an NDL diver with "deco-tention."

I initially thought that you might just be curious to see your computer in deco mode. I would be too....

I was curious as well. But, I did get to find-out how my computer would react to a 306fsw dive with a 20 minute bottom-time, ignoring the required deco-stops, and ascending way to fast. I learned that it will indeed lock you completely out of computer mode for 24 hours. What we really learned from doing it was that the downrigger's depth counter was pretty accurate. The downrigger said 300 feet of line was out, while the computer said max. depth was 306 feet. Not the best way to check, but effective.

 

[Blackwood]

I'm sure that everybody would start quoting "agencies" for training, but really, decompression theory isn't all that hard. It ain't rocket science.

Much of the math that goes into decompression algorithms is more complicated than rocket math.


In any case, having enough gas is by far the prevailing factor. I don't know what's dumber: knowingly going into deco without having adequate gas, or accidentally going into deco. Actually, I do.

 

[Blackwood]

1. If you bouyancy is not sufficiently expert to ensure you can hold a stop in mid-water, without reference and without rising or sinking by a few inches (not meters!), then you should NOT do deco, either by purpose or accident.

inches? Come on, now. I know what you are saying, but squabbling over inches in a stop is absurd. Most depth gauges probably have less resolution than a few inches, or aren't properly calibrated throughout the entire depth range to properly read depth on the order of inches.

I'd put it as follows: Have good enough control to stay where you intend to in all three dimensions.

 

[tgsmith]

Much of the math that goes into decompression algorithms is more complicated than rocket math.

That's funny. I actually happen to know a legit rocket scientist. No.....seriously......he designed several rockets that put satellites in space.

I'll ask him what he thinks. He gave the best explanation/description of gradient factors that either I or our instructors have heard.......

 

[Blackwood]

That's funny. I actually happen to know a legit rocket scientist. No.....seriously......he designed several rockets that put satellites in space.

I'll ask him what he thinks. He gave the best explanation/description of gradient factors that either I or our instructors have heard.......

When I was in school (aerospace engineering degree), I didn't care much for propulsion (rather I took as many fluid mechanics and aerodynamics classes as possible - now I design spacecraft structures and mechanisms... no air... go figure), so I only did the bare minimum in terms of rockets. While liquid rocket engines are far more complicated than solid rocket motors, I don't remember any differential math in either.


I'd be interested in his GF description. As I understand them, they aren't that complicated.

 

[ianr33]

inches? Come on, now. I know what you are saying, but squabbling over inches in a stop is absurd.

Not if you have a bottom timer that counts in seconds

 

[tgsmith]

When I was in school (aerospace engineering degree), I didn't care much for propulsion (rather I took as many fluid mechanics and aerodynamics classes as possible - now I design spacecraft structures and mechanisms... no air... go figure), so I only did the bare minimum in terms of rockets. While liquid rocket engines are far more complicated than solid rocket motors, I don't remember any differential math in either.


I'd be interested in his GF description. As I understand them, they aren't that complicated.

I'm sure he'd be delighted to entertain you if you fly to the east coast and meet up with him for lunch.

Directions to drive somewhere aren't complicated either, but I've had a lot of very, very bad directions given to me that landed me in areas of D.C. I didn't want to be in. But hey, I'm no engineer so whatever......

 

[Web Monkey]

That's funny. I actually happen to know a legit rocket scientist. No.....seriously......he designed several rockets that put satellites in space.

Minor hijack:

When I first got out of college, my first software job was a pretty large project, and I was completely buried. I told my boss that I needed help, so he hired some guy that couldn't reliably work the fry-timer at McDonalds. I complained and he got me another assistant, slightly better but still no help. I complained again and after a few days, he said "You'll really like this guy." I said "What did you get me? A Rocket Scientist?"

It turns out that he did get me a Rocket Scientist. The guy was from China and actually was a Rocket Scientist. He was amazingly brilliant, but unfortunately vanished a couple of days later and I never saw him again.

Terry