Farnsworth Banks accident last weekend?

[MaxBottomtime]

My impression of Fransworth Banks is of a series of steep pinnacles connected by narrow saddles that form a kind of winding underwater ridge line, which does not reach the surface at any point, and is surrounded by deep water. This is probably an oversimplification, and no doubt other readers of this board can provide more detailed descriptions. What makes this site tricky, in my opinion, is without good navigation, including an accurate heading back to the up-line, it’s all too easy to go in the wrong direction when returning.

Agreed. I've lost my anchor there before and it's not much fun making a free ascent when there could be a strong surface current.

 

[Ricky B]

You cannot meaningfully answer that question without considering (a) how much gas you and your buddy use, on average (i.e. your gas consumption rate),

An excellent post, Bob. I would add, as a footnote, that not only should a diver be checking his (or her) air regularly, but he should also be giving his buddy the "check gauge" sign (and get a reply as to air status) as well. And the buddy should be doing likewise. If each diver in a buddy team is not looking out for the other, the divers should realize that they are diving solo.

If you're at 1800 psi when your buddy is already at 1200 psi, waiting until your air reaches 1200 psi to suggest surfacing from significant depth, your buddy (who is apparently not keeping track of his air) is probably going to be low--too low--on air. If you are regularly checking your buddy's air as well as your own, you'll have at least a rough sense of how quickly to end the dive.

 

[Bob DBF]

I don't want to sound too critical after a fatal accident, but it's obvious there were at least two serious errors here. Not only are you not supposed to run OOA but you need enough for your buddy in case. If you don't have an AI computer a useful rule of thumb is to have PSI>= (depth in feet)*10 + 500. So at 100 feet have at least 1500 psi to allow yourself enough for ascent and to share if needed. If you have an AI computer, Oceanic, UWatec or Cobalt, if you ascend before your RBT>0 you're unlikely to run out of gas. An if (RBT in mins)> (depth in feet)/30 +1 and have a reserve set to >550 psi, you'll have enough to share with your buddy as well.

The most likely reason the diver panicked and emptied his BC with an OOA buddy is that he was OOA as well. Using an AI dive computer would likely have prevented this death. IMO.

Just to add: there is a good article on AI in the latest issue of Undercurrent.

They were at the safety stop with air.

I'd say one error, they split the buddy team. They should have both surfaced, swam back to the boat, and taken the a** chewing for not finding the anchor line. I've been reamed for missing the line before but I won't take chances to make it look like I didn't. When things are not going well, the surface is your friend

I wouldn't rule out a medical issue, pretty stressful doing a blue water ascent, holding a stop, low on air, and waiting for your buddy to come back.



Bob
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I may be old, but I'm not dead yet.

 

[dytis-sm]

They were at the safety stop with air.

That is what puzzled me. If you are running out of air why not blow the safety stop. It is better to get the bends rather than drown. Maybe a little panic and tunnel vision settling in, or a mechanical failure (stuck bcd vent and being "overweight")? ...very mysterious indeed.

 

[Hatul]

They were at the safety stop with air.

I'd say one error, they split the buddy team. They should have both surfaced, swam back to the boat, and taken the a** chewing for not finding the anchor line. I've been reamed for missing the line before but I won't take chances to make it look like I didn't. When things are not going well, the surface is your friend

I wouldn't rule out a medical issue, pretty stressful doing a blue water ascent, holding a stop, low on air, and waiting for your buddy to come back.



Bob
----------------
I may be old, but I'm not dead yet.

I see it the other way around. If the details provided by Randar are accurate they either miscalculated or were not watching their gas supply on a fairly deep dive. Either way it's an inexcusable error. Not finding the anchor line is understandable, as it can be hard to navigate back in California viz and you can go through a lot of air at depth trying to find it.

 

[Bob DBF]

I see it the other way around. If the details provided by Randar are accurate they either miscalculated or were not watching their gas supply on a fairly deep dive. Either way it's an inexcusable error. Not finding the anchor line is understandable, as it can be hard to navigate back in California viz and you can go through a lot of air at depth trying to find it.

Randar
I am not sure what their "Pressure readings" were at their safety stop, so I cannot answer why the buddy went OOA. The buddy left the safety stop to "get a fix/heading" to the boat. When he returned, the other diver was at 30+ feet and descending with air venting from his BC. It was at this point the surviving diver went OOA and surfaced in a panic. Because of the quick and concise reaction of the Boat crew, we were able to recover the OOA diver quickly and get a safety diver in the water to begin searching.

They both had air at the safety stop, they both should have surfaced. And yes divers should have kept better track of their air, I have found it much easier after SPG's came into common use.




Bob
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That's my point, people, by and large, are not taught that diving can be deadly, they are taught how safe it is, and they are not equipped with the skills, taught and trained to the level required to be useful in an emergency.

 

[Steve_C]

This may be irrelevant but I have had a couple of dives while traveling where I rented a BCD that had a different button arrangement then my regular BCD. More than once I pushed the wrong button, or pushed where there was no button when wanting to make a small air adjustment. Was only a minor nuisance and I became more careful about what I was pushing.

 

[Randar]

Bob...

Points of clarification. The location where the buddy surfaced (away from the line) was not very far from the boat. Easy swimming distance. The buddy was however, in a panic due to OOA and the Zodiac picked him up. There was NO current and the viz was 50-100' I have dove Farnsworth 5 times now and each time it has been different. This particular day though, was the best conditions I have personally seen.

As to your air management formula. Great in theory, but, each diver is different in physiology and consumption rate. You need to be aware of your consumption rate and plan/recalculate based on changes in that. My computer tells me time remaining based upon the changes throughout the dive. For example. I did a very similar profile on that same dive...down to 130 Chased my zero remaining bottom time up to 60 feet, did a 2 minute deep stop which ended with 850-900 PSI, slow ascent - not on the line (I could see the boat from 60 Ft) (30 FPM) did a full 5 minutes at 15 feet and still landed on the back deck with just a bit over 500 PSI.

I have to agree with several who have said that Blue water, free accents can be VERY stressful. (Been there done that, have the shirt) But, if properly managed/practiced, they are relatively easy. I have done many in Murky Green Northwest waters with less than a foot or so of viz. I use my SMB, and make a slow casual ascent up my line.. But, if you haven't practiced it and have to do it on the fly, well, big time stressor. Additionally, the boat had and deployed their zodiac. And regularly briefed that "If you are having issues, signal and we will come get you" Which is exactly how it went down.
Not sure the buddy team was an issue either. The split was VERY short duration...Pop up take a bearing and descend.

I am still pondering weight ditching. What is it that causes a diver at 15 feet to keep descending and NOT ditch all weights in an Emergency. This is the second recent case of this that I am aware of. PADI has changed their Curriculum and Standards to focus and emphasize the ditching of both belt and integrated systems. When I do refreshers or help with classes I always ask "If you were OOA at the surface or near the surface, how could you become more buoyant. I am surprised by the answers I get at times. #1 answer I hear is "Orally Inflate BC"

If nothing else, I hope this accident reinforces instructors and AI's, DM's to teach and reteach weight ditch and other skills (SMB deployment, air management, Nav) And also take the time to really look at a divers ability and feel compelled/obligated to point out flaws or errors in a divers planning, practices and logic. Also for the Non Pro divers; Take time to PRACTICE!!! SMB's Nav, Buoyancy, OOA EP's etc etc.

~R~

 

[dytis-sm]

Bo

I am still pondering weight ditching. What is it that causes a diver at 15 feet to keep descending and NOT ditch all weights in an Emergency.

Weight ditching is not practiced often if ever and when one is panicking and experiencing "tunnel vision", probably not the first thing they will do. I have come to this realization in a couple of scenarios I was stressed underwater (not panicking to clarify) where I may have not reacted the way I was taught/trained. As Bill Powers mentioned once on a diving trip (got to give credit where due) divers need to develop the "muscle memory" to ditch weights. He recommended practicing often using visualization and on land where you would just visualize a situation and drop the weights on the ground. Not a bad idea, although practicing this skill in the water it would be even better...

BTW, nobody brought up the issue but could narcosis at depth play a role on losing track of air... I wonder how deep did they get before this whole story unfolded.

 

[Jan Kruger]

Just a few comments after reading some of the above replies.
What a Tragic event once again.
I feel if you know you are going to do a deep dive( deep in my opinion for normal AOW divers) .
1) Choose your buddy well...deep diving has additional factors like Narcs, possible darker dive than shallow dives , you use your air much quicker than when diving shallow depths , possible streams , possibility of larger sharks & Barracuda.
You also take longer on the return trip to the surface. So make sure you choose a buddy that is well trained , experienced and cool under pressure.
2) Dive often ...even shallow dives to keep the head into safe diving. We dive in stupid quarries at least once a month ...not to explore ...the vis is anyway not good in the quarries we dive in.. but to practise our skills and to keep our heads into safe diving . To get to know our buddies abilities and to try out our newly learnt skills.
3) Like with clearing your ears, check your air often! I once did a dive to 40 + meters with a bud that was well trained , cool under pressure and checking with me on our air . We had to ascend earlier than the rest of the group because of me sucking my air quicker than anybody else. Luckily we did not have our cameras with on that dive .
4) Ensure your diving gear is in good working order. Check your air before diving.
5) Take good note of the dive plan when explained at the briefing . Stick to the dive plan.
6) Stay close to your bud.
7) Enjoy it !!!