Free ascents

[ArcticDiver]

.....

 

[nereas]

Although I would hate to make a free ascent while drifting in the open ocean, I would certainly choose it over blowing off a significant decompression obligation.

Exactly. Any decompression obligation.

 

[underwasser bolt]

drifting while decompressing is doable, but may still get you killed. if you drift too far from the boat, they may never see you, even if they are looking. emergency gear increases your chances, but you are still in a world of hurt ascending without a reference just for the fact that you can drift miles away during the time of decompression. 60 miles off shore, being lost at sea is likely a death sentence. a very slow death.

 

[nereas]

drifting while decompressing is doable, but may still get you killed. if you drift too far from the boat, they may never see you, even if they are looking. emergency gear increases your chances, but you are still in a world of hurt ascending without a reference just for the fact that you can drift miles away during the time of decompression. 60 miles off shore, being lost at sea is likely a death sentence. a very slow death.

This is why to carry an up-line.

And this is why to dive with a buddy who also carries an upline.

Now you have 2 of everything, between the 2 of you. And you need to be sure your up-line is good quality, since you life depends on it.

In conditions with a current, a DPV for each is also an excellent idea.

Drifting is a last resort.

Blowing off deco is not a viable resort, and is most likely a non-commutable death sentence.

 

[rawls]

Doc made alot of very valid points. My experience using a surface bag was in a very controlled environment. I dive the Atlantic and yes, we do practice hangs out there but only when the seas are very calm. We shoot the bag just as the dm takes up the anchor from the wreck. During these drills we come up a few yards from the boat. Since the anchor is up, the dive boat can stay close by if by chance we start to drift. There is also a crew member in the water with us and a couple on the ready onboard. It is actually a fun drill in this manner. Being in a real situation...I wouldn't want to do it. Like Doc said, most of the time there is some current. Sometimes it is kicking. I have known divers who...after the captain briefs the dive and says more than once...STAY ON THE ANCHOR LINE ON DESCENT AND ASCENT...let go of the anchor line and away they went. And...again as Doc mentioned...there are a couple of divers each year that experience that away they go and never come back.

I went back and read the chapter and the autopsy stated that death was due to "drowning and barotrauma due to rapid ascent in salt water."
Again, this sounds to me like a lung overexpansion injury. If that was the case then he held his breath and was most likely paniced. He could have possibly not held his breath but still suffered a lung overexpansion injury if his ascent was so fast that he couldn't exhale expanding air fast enough. In any event barotrauma sounds like lung overexpansion. Not enough details. But he did hit the surface unconscious. My guess is he probably ran out of air...just a guess....China Fever...

 

[Kevrumbo]

I have read a lot of the discussions about drift deco versus hanging on a line, and the issues are very real, even to me, who has never been in that position. What baffled me about the account, though, was that, once his upline frayed and broke, he had two choices -- blow off deco and surface at the boat and hope to survive it, or drift. Either he couldn't perform a drift deco ascent, or he made a bad decision that he could blow off that much deco. It does seem like being caught between a rock and a hard place. Do divers on these wrecks ever consider carrying EPIRBs? That's what I've heard the folks diving in the Galapagos do, where currents can be horrible. (It doesn't solve the being run over by a freighter problem, but at least one might be found . . . )

Yes . . .For Tropical Deep/Wreck Trips in the middle of nowhere, I actually stow & buttmount a folded Halcyon Diver's Liferaft --in addition to a McMurdo Fastfind GPS plus PLB in dive canister. . .

Shoot the SMB from depth and perform a drifting Deco (Jersey Reels and makeshift uplines are old school & obsolete IMO); if fog prevents diveboat from seeing your SMB or you post-Deco floating on the surface, last resort is to deploy the PLB; alternatively, a Uniden Mystic stowed in a dive canister (I keep mine inside the body of my X-Scooter) could be used to selectively call the diveboat for pick-up as well. . .

 

[grazie42]

Without being on the dive I don´t know what was going thru the divers mind or if his decision was right/wrong...don´t really feel like specualting either...

In general terms I feel there would have to be something really extreem to make me ignore a decoobligation. People have survived drifting at sea for days and I´d rather "die later than die right now"...

For boat-diving an smb is something you need, imo, so I carry 2 (as do all my buddies). Some boats have a protocol where you shoot 2 smbs together if there´s something wrong, on those dives I carry 3. I have one orange, one yellow and an orange liftbag because some boats use colour-coded systems to convey information(ie missed upline or emergency)...I also carry an extra slate to attach to an smb should I need to/be able to communicate with the boat...If I were to get blown off a deep wreck in a ripping current I would (and have) shot a bag right away with my reel (sub 150ft) so that the smb pops up close to the boat and then "take my time" with a drifting deco...

I´m also comfortable doing ascents without reference and do so once in a while to keep my comfort-level. If you do deco dives where something as minor as not having an upline can get you hurt, I think you should reconsider whether you are fit to do those dives...

I´ve never tried to use an upline but it would be fun to try (in somewhat benign conditions)...

ymmv

 

[rjack321]

I have read a lot of the discussions about drift deco versus hanging on a line, and the issues are very real, even to me, who has never been in that position. What baffled me about the account, though, was that, once his upline frayed and broke, he had two choices -- blow off deco and surface at the boat and hope to survive it, or drift. Either he couldn't perform a drift deco ascent, or he made a bad decision that he could blow off that much deco. It does seem like being caught between a rock and a hard place. Do divers on these wrecks ever consider carrying EPIRBs? That's what I've heard the folks diving in the Galapagos do, where currents can be horrible. (It doesn't solve the being run over by a freighter problem, but at least one might be found . . . )

Yes, although they need to be in a pressure proof canister. Only recently have EPIRBs gotten small enough to make this useful. The intergral GPS EPIRB/PLBs have a much shorter response time (15 mins). The older non-GPS types required 2+ passes by the satellites to get a position fix and that could mean you are flaoting for a couple hours before they know where you are. All EPIRB/PLBs use a 121.5 Mhz signal for final homing. In this case it would be by helo. Well discussed issues on TDS.

Locally EPIRB/PLBs and recommended for diving Duncan Rock and other Neah Bay sites.