RE: Fishing under the ice.
January 3, 2012 at 8:52 pm
(This post was last modified: January 3, 2012 at 8:56 pm by Jackalope.)
(January 3, 2012 at 6:40 pm)Cinjin Wrote: Amazing.
Ice cold, upside down, breathing through oxygen tanks with no visible escape route thanks to the ice.
Just amazing .... crazy and stupid ....but none the less amazing.
Surprisingly, in a dry suit, it's not as cold as you might expect. I've done hour-long dives in 33-34F fresh water without being uncomfortably cold. A substantial insulating garment is worn under the waterproof dry suit. I used to routinely dive in water down to the low 40's in a wet suit.
In a neutrally buoyant environment, "upside down" is relative. NASA trains astronauts for spacewalks in giant pools for a reason.
Tanks aren't filled with oxygen, it's typically either ordinary air, an enriched oxygen/nitrogen mix, or something more exotic. Oxygen is toxic at depth and is only used for off-gassing nitrogen at very shallow depths
As far as there being no visible escape routes - that's one of the reasons why it's extremely hazardous. There are protocols that are followed that allow a safe return to the entry point, even in zero-visibility conditions.
I've been trained in wreck penetration (which is similar to ice diving in many respects) and one thing I can tell you is this: you either plan these types of dives (including contingencies) before you get in the water and dive them to the plan, or you count on being very lucky. I prefer the former.
I have no idea if the divers have had the recommended training or are what safety protocols were in place during the production of this video.
P.S. It's also worth mentioning that diving in overhead environments (i.e. where an immediate vertical return to the surface is not possible for any reason) is advanced diving and requires far more training than the average recreational diver has.