Diving incident at Eagles Nest Sink

[tbone1004]

@KevinNM you'll have to ask @Dsix36 or @PfcAJ as I haven't done either of the dives. Hence why I didn't comment on whether it was enough or not.

I still won't comment on whether it was enough, because by their calculation it may have been, and/or should have been, but these are my thoughts.
The 4 man team went farther back with the same amount of bailout/diver. If the other passage is free of restrictions, is scooterable the whole way, and with 4 guys instead of 2, you could argue that you have less need for bailout and I'd be OK with that. You can go into a team bailout scenario if you have to, and should be on the trigger most of, if not the whole time. Depends on how they did their dive plan, if it was not based on having to kick out because of the backup dpv, if it was assumed that it should be enough for one diver but if it really hit the fan then you can go to team bailout etc. etc. I wasn't there on either of the dives and don't know how either of them planned it.
By my math the 2 diver team had enough to kick out if they didn't get stuck somewhere. One of the things that I feel is rarely discussed in OC bailout planning is time to correct incidents. If you have enough to kick out and you are using a slightly elevated sac rate, and a slow kick speed, then you should be fine. What happens if you get caught in the line and tied up for 2 minutes trying to untangle something? What happens if you get stuck somewhere, lose the gold line, silt out etc. At 100ft, even 5 minutes isn't likely to kill you from running out of gas, but 5 minutes at 300ft is a LOT of gas... They could also have had a similar team bailout strategy. One of the guys may have been more experience at navigating restrictions, so if there was a major problem, they could have agreed upon team bailout instead of carrying a lot more bottles that would have impeded their ability to move around etc. Lots of ways to skin that cat

 

[PfcAJ]

Are there as many and similar restrictions getting to this room as there are getting into Revelation Space? I can't find the the Abyss room or the landmarks to the Abyss room on any of the maps I can find.

There are 3 restrictions on the way to the abyss room. Haven't been to revelation space so I can really compare.

 

[kensuf]

There are 3 restrictions on the way to the abyss room. Haven't been to revelation space so I can really compare.

And the restrictions to the Abyss room are rock, not clay.

 

[bamafan]

When I started cave training my instructor told me to always plan for any 2 failures. Ignoring the cause of the failures these guys had more than that so to make it as far as they did was a feat in itself. Definitely some lessons to be learned.

 

[apitkin]

The Abyss Room is a much more straightforward dive than Revelation Space. The Abyss Room was first explored in the early 90s by Larry Green, Jim King, Sheck Exley and George Irvine. Exley and subsequently Green and King had seen the restriction at the end of the Room of Dreams (what we are now calling the Revelation Space restriction) but did not like the look of it and so decided to try an opening on the west wall instead. This opened up into a tunnel at 290 ffw that Jim King named after his son Andrew, and when they ascended the rock pile at the end, negotiating another restriction, they were so overwhelmed with the size of the room they found that they succumbed to hyperbole and named it 'The Abyss'. It is a spectacular place, the biggest room in the system.

Revelation Space was explored in 2010. Although it only adds one real restriction (and another low area) after the Pit, that restriction is siltier, longer and more complex than either of the hard rock openings en route to the Abyss, which explains why the Abyss Room was visited many times before Revelation Space was ever explored, and why it makes a good stepping stone for divers who want to visit Revelation Space.

The Abyss Room is much bigger than shown on this map fragment (my addition to Eric Hutcheson's map). Andrew's Tunnel also trends more southwest, rather than due west or slightly north of it as shown here.

Andy

 

[Dan]

Thanks for posting the map. That help me visualize what's going on in the Revelation Space too. I see the Halocline Room, between the Room of Dreams and the Revelation Space. I've been diving through halocline zone where the vision become hazy fuzzy as you dive through the zone and mixing up the salt & fresh water. I wonder if that can cause difficulty to locate the restriction.

 

[KevinNM]

Yes, thanks for that map.

 

[Ron Lee]

I have a question for the second dive team members. The first team probably went in with a thought that it could be a rescue. The comment months ago after I asked is that the second dive team had no such thoughts. Considering the time of day (night) and the possible fatigue level, was it really prudent to dive when they did?

This dive site appears to be challenging under good conditions. Throw in fatigue and it would seem to raise the risk level.

Go back to the Colgan plane crash in Buffalo. My recollection is that crew fatigue played a factor in that deadly crash.

Are there, and if not, should there be standards on when you make dives like this if there is no reasonable chance of it being a rescue dive?

 

[lv2dive]

Time of day doesn't impact cave divers - it's always night in the cave. (Not the member of the second team, but I have dove the Abyss room!)

I have a question for the second dive team members. The first team probably went in with a thought that it could be a rescue. The comment months ago after I asked is that the second dive team had no such thoughts. Considering the time of day (night) and the possible fatigue level, was it really prudent to dive when they did?

This dive site appears to be challenging under good conditions. Throw in fatigue and it would seem to raise the risk level.

Go back to the Colgan plane crash in Buffalo. My recollection is that crew fatigue played a factor in that deadly crash.

Are there, and if not, should there be standards on when you make dives like this if there is no reasonable chance of it being a rescue dive?

 

[Roderick80]

A summation of known facts on this tragedy was posted to the NSS-CDS site earlier today:
October 2016 Eagles Nest Tragedy, Revisited - NSS CDS