Lake Pleasant, AZ, adjust for altitude?

[FreeFlyFreak]

This is what the manual says.
I assume this means that the appropriate corrections for diving at altitude are applied no matter what altitude you are at.
So, in effect, every dive that starts above sea level is an altitude dive....it is just that the corrections are insignificant unless you start at...300 ft? 1000 ft? Unclear...but by 1000 ft they must be significant enough for USN/NOAA to worry about them.
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Which is why the Shearwater manual recommends turning the computer on before the dive to get an atmospheric pressure before submerging.

 

[broncobowsher]

Are you the coroner and medical examiner? Are you quoting from some official report I've missed?

What was missed was this was originally in the accident page. Thankfully Admin ripped all the altitude stuff out of the accident page and threw it into the local page. So you get it a little out of context. Hopefully the accident page will be a little more considerate of the accident and not into the irrelevant tangent of Lake Pleasant being an altitude dive or not.

Now if you want to really get into the nitty gritty of altitude diving or not, the actual altitude doesn't matter. It is the air pressure (typically from altitude) that matters. But if you talk to anyone who has had there basic flight classes there is another factor that plays in, altitude density. Just because you are at a specific altitude does not mean that is a fixed air pressure, weather will alter those numbers. A good computer (like the shearwater) will look at surface baro pressure and use that as a starting point. Some of the dive planning software will allow you to input the altitude and even an altitude that you have been normalized to before getting to the location So you can plan a 2000' elevation dive after being normalized at 1000' (Phoenix-ish elevation) where most live.

But for the accident that this was spun from, it was a problem that developed at depth, before surfacing and experiencing whatever the surface air pressure would be. So for that elevation cannot be a factor in the accident as the problem started before it could be a factor. And thus Admin made the new thread for elevation separate from the accident. Thank you admin for cleaning up the accident page so it can be more respectful of the accident itself and not some rant about my computer does this, these tables do that, and all the normal SB bickering can be spun off into this thread.

Have you gone and looked up density altitude yet?

 

[PBcatfish]

...
Have you gone and looked up density altitude yet?

I'm just going by 30 year old memories from flight school here, but I remember altitude density being something that related to lift, stall, & wing efficiency. I'm not familiar with it having a direct impact on pressure related effects on the human body. I seem to remember that humidity effects density altitude. I am not aware of humidity affecting my dive profile. Did I miss something?