Coast Guard Cutter Healy Deaths

[Tigerman]

The medical examiner "may" have had access to equipment that would have presented that information to him/her. Maybe even a dive computer.

Again we dont have enough information yet to form conclusions or observations

Im just thinking.. I use what? 2 minutes to 100 feet? that would mean 4 maybe to 200 feet? And that is not swimming but "floating" down. If you swim, you should be able to get that deep much faster? It need to be one bad downcurrent to be able to pull someone down so fast its conclusively impossible that it was a unplanned, yet concious swimming descent? As i was in the first thread and also still am.. Just thinking loudly, but atm, it dont make sense to me that a coroner can say for sure if it was uncontrolled or not.. Unless of course it was a 20 second drop from 20 feet to 200 feet that is..

 

[DiverInAk]

The umbilcal should have a safety line, comm wire, air hose and possibly a hot water hose.

That would have been a life saver here. They were diving single steel tanks with full face masks. The "umbilical" was a yellow polypro line.

Though it's open to debate whether the tenders actions would have had different final outcomes, I would say that the tenders certainly should share in the responsibility. It's a heavy burden for those folks I'm sure.

 

[Capt Tom McCarthy]

There definitely are a lot of questions that still need to be answered. How could the tenders let out 180 feet of line when the dive was scheduled to be to 20? Everyone seems to be forgetting that dives go both vertical and horizontal. The tender could have easily thought the divers were swimming horizontally at 20 feet for 180 feet. Although I would assume an uncontrolled descent for that distance would pay out line much quicker than normal swimming. But what cause an uncontrolled descent? And in both divers? My first thought when I heard this was "bad gas." It is possible to fill tanks in a manner where the intake for the pump is downwind of an engines exhaust causing carbon monoxide to enter the tank. However I would assume that the coast guard would check the tanks for Carbon monoxide after the divers died. Unfortunately they said one tank was empty and the other had 90psi left. Which brings me to my next point. 90psi. At depth air in a scuba tank will not escape if the pressure in the tank is equal to ambient pressure. Every 33 feet of sea water is 14.7 psi of ambient pressure. So a tank that's "empty" at depth might still have air at the surface. This is the reason they tell divers out of air to ascend with the regulator in their mouth because there may still be a breathe or two in the tank once they are shallower. Anyway. 90psi divided by 14.7 psi per 33 feet = 202 feet. Not saying that‘s the exact depth but it was around there. It's possible the person ran out of air at that depth died and was pulled to the surface by the tenders. This is also strange for another reason. If the regulators "free flowed" a condition most likely caused in this case by freezing water in the first stage of the regulator keeping it in the open position. The remaining 90psi most likely would likely have escaped as the diver was pulled to the surface of the one tank. I believe the diver with 90psi was attempting a rescue. The first diver with 0 psi remaining. Could have had a freeze up that prevented them from adding air to their B.C or dry suit and continuously free flowed air out the second stage. Causing them to plummet uncontrollably. The other diver went after them and in the process ran out of air. 180 feet is very deep for a single tank and the air wouldn't last very long. Especially if they had a free flow. There is also a possibility of buoyancy compensator exhaust valve sticking or other strange things. One thing to remember about diving accidents is there is a domino effect. One thing leads to another and another and another. If you don't take care of the first problem first you'll usually end up in serious trouble. We can only hope we can find out what really happened so we can learn from their deaths. If you don’t agree with some things just politely suggest other opinions, this is just a hypothesis and in no way is set in stone so don’t crucify me if you disagree. Safe Diving.

 

[Rick Murchison]

All this speculation and guesswork is pointless.
The Coast Guard has an investigation underway.
When it's complete, we'll most likely have a very clear picture of what happened and how to prevent a similar mishap in the future.
Rick

 

[Tigerman]

...
There is also a possibility of buoyancy compensator exhaust valve sticking or other strange things. One thing to remember about diving accidents is there is a domino effect. One thing leads to another and another and another. If you don't take care of the first problem first you'll usually end up in serious trouble. We can only hope we can find out what really happened so we can learn from their deaths. If you don’t agree with some things just politely suggest other opinions, this is just a hypothesis and in no way is set in stone so don’t crucify me if you disagree. Safe Diving.

Now this could be a possible answer to my "how can the medical examiner know it was an uncontrolled ascent, if the exhaust valve was still stuck at full opening when the divers was recovered.
I have seen the opposite happen, that the intake valve stuck on open, causing the bcd to constantly be filled, making the dump valve "free flow" as the pressure got too high.. The result of course was nearly that my buddy went from a 100 feet wreck dive and taking the express elevator to the surface. Fortunately she got hold of the line going from the wreck to a bouy so that she could hold on to the line and get some safety stop/deco before going up. She went at 250-300% speed from 60 ish feet to 15 feet, so i guess a little extra time on 15 feet didnt hurt..
The valve that was stuck was still stuck when we surfaced..

 

[Capt Tom McCarthy]

All this speculation and guesswork is pointless.
The Coast Guard has an investigation underway.
When it's complete, we'll most likely have a very clear picture of what happened and how to prevent a similar mishap in the future.
Rick

Hmmmm... I hope it's still underway. The press made it out to sound like the case is closed. Have you heard otherwise? I waiting this long to speculate because I was under the impression that the case was closed with the idea that they would never really know what happenned.

 

[TSandM]

The snippet of autopsy report is confusing to me as well. I would assume and hope that there was a dive computer or recording depth gauge that gave them the information about the descent and ascent. An uncontrolled descent from 20 feet makes me think about something that would prevent the diver from inflating either dry suit or BC, which means valve off (but that would end up with a tank FULL and not empty) or first stage failure, or diver unconscious or incapacitated at the beginning of the dive (eg. bad gas). Since this involved both divers, bad gas would certainly be a reasonable possibility. But a completely unconscious diver on the basis of carbon monoxide or hydrocarbons in the breathing gas mixture would most like not have the reflexes to protect the airway, and therefore shouldn't develop pulmonary barotrauma, even with a rapid ascent -- I'm assuming the ascent was the tenders pulling in the line, because that's the only way I can think of that an incapacitated diver is going to get back to the surface.

But that gets back to a question that shakybrainsurgeon asked a month or so ago, which is whether there is some speed of ascent which would be rapid enough that air expansion would exceed the capacity of the small airways to allow it to escape, so that you could get barotrauma with an open airway. This was debated, but nobody really knew.

So, from a medical standpoint, given the information quoted, I'm still confused.

 

[Airborne!]

The Medical Examiner simply determines probable cause of death based upon Medical examination of the body. Not how they died, but why they died. Not saying they don’t take into account the circumstances, but you do not want them to have preconceived ideas which might make them miss something important. Their report is simply a small part of the investigation that the Military system uses. The report is not supposed to determine the cause of the incident although the media usually jumps on it like it is. The Media makes people think that the Medical Examiner is somehow investigating the incident which is not the case at all. They are just investigating the body and what happened to the body.
Having been part of these types of investigations in the Military I can tell you that they are in no hurry to put out the final report. They work along the lines of being thorough and complete rather than swift. Even when the cause seems plainly obvious it can take a year before the final report is done. You have to remember that the investigation is not just to find the cause, but to prevent its reoccurrence. Jump to a quick conclusion and someone else could die because you missed a small but important part. You would be amazed at how you can look at a piece of information or equipment 5 or 6 months after the fact and wonder how in the world you missed something so obvious or critical.

 

[Capt Tom McCarthy]

or diver unconscious or incapacitated at the beginning of the dive (eg. bad gas).

I thought about the bad gas thing myself. But if they had bad gas the divers would likely have blacked out quickly into the dive and stopped breathing. How would their tanks have gotten down to 0 and 90 psi then?

 

[Rick Murchison]

I say again:

All this speculation and guesswork is pointless.
The Coast Guard has an investigation underway.
When it's complete, we'll most likely have a very clear picture of what happened and how to prevent a similar mishap in the future.
Rick

Y'all insist on spitting into the wind.
Be patient; the CG is estimating a report release early next year.
Rick