Possible death on the oriskany Nov 14, 2009

[lamont]

I don't have any info on the acccident but want to comment on a couple areas.

For future reference in your own mind because some have sort of agreed to disagree....

In the police diving world studies have been done relating to speed of currents(It has to do with the amount of current to move a body) and it has been found that a diver in good physical shape can maintain a sustained maximum speed of 1.8mph (2kts). So if you can swim against it, it is two or less knots, etc.

The foam mentioned by one of the witnesses may have nothing to do with embolisms or closed airways. It is very common in drownings whether SCUBA is involved or not.

The Reader's Digest version is that this Surfactant being produced has to do with the irritation of the alveolar lining cells by the inhaled water resulting in increased mucus production and blood plasma entering the lungs during a common antemortem gasp.

There is, at this point, no reason for those involved in the attempted rescue to think that they may have done something to cause an embolism.

2 kts is roughly 200fpm which is roughly the speed of a scooter and i can't keep up with a scooter...

i did manage to match speeds for about 2 minutes with a 'cuda on default when it was towing two divers, and gave myself a nice buzzy CO2 hit at 60 feet that took awhile to clear up...

 

[deepstops]

I don't have any info on the acccident but want to comment on a couple areas.

For future reference in your own mind because some have sort of agreed to disagree....

In the police diving world studies have been done relating to speed of currents(It has to do with the amount of current to move a body) and it has been found that a diver in good physical shape can maintain a sustained maximum speed of 1.8mph (2kts). So if you can swim against it, it is two or less knots, etc.

The foam mentioned by one of the witnesses may have nothing to do with embolisms or closed airways. It is very common in drownings whether SCUBA is involved or not.

The Reader's Digest version is that this Surfactant being produced has to do with the irritation of the alveolar lining cells by the inhaled water resulting in increased mucus production and blood plasma entering the lungs during a common antemortem gasp.

There is, at this point, no reason for those involved in the attempted rescue to think that they may have done something to cause an embolism.

PubMed search shows "a strong swimmer can swim upwards of 2 to 3 km in an hour" so I think your data applies to swimmers, not divers in full gear.

 

[ditch-diver]

It was done with divers in full gear...., trust me. Either that or someone pulled a joke on me and I swam with gear on for nothing. AS for pubmed, My 400 and 800 swim times put me at over 3.2km/hr and I'm not a good swimmer.., below average in our circles.

It take roughly a 1.5 kt current to move a body once it is one the bottom. The general rules for PSDs is if you can make headway against the current a body won't move.

Perhaps you are just not a strong a swimmer as those highly trained athlethic cops used when the study was done. Donuts are made with steriods you know.., that's why we eat so many of them

 

[bleeb]

ditch-diver, can you clarify the following statement you made earlier? There might be a typo of some sort that might be causing a bit of confusion.

it has been found that a diver in good physical shape can maintain a sustained maximum speed of 1.8mph (2kts). So if you can swim against it, it is two or less knots, etc.

1.8 miles per hour is not exactly 2 knots, more like 1.6 knots. (1 knot = 1.15 mph). Or 1.85 kph = 1 kt. (2 kt = 3.7 kph) Or was it only meant to be an approximation, although the extra 0.4 kts (0.7 kph) would seem to be a bit when swimming (or diving.)

 

[ditch-diver]

Good catch bleeb.., that is why I should stay off the computer when drinking Rum. The 1.8mph is accurate speed, the 2kts was my bad. I screwed up the conversion (flipped the 1.1 to 1 ratio) to compare it to the knots needed to move a body. My mistake all the way.

Didn't mean to hijack the thread.., just wanted to give people a way to estimate current speed when they are in the water.

 

[rigdiver]

To get back on topic: Does anyone know if the deceased was diving a He based mix @ 165fsw?

 

[twood]

Hello,

I am not a diver, but I knew Tim and his wife. I have been trying to find out what happened to him. I Google searched his name and found this thread. I have to say I have found more about what happened from this one thread than anywhere else. However, I have not been able to find the cause of death. Has anyone heard or read anything more?

For those that were on scene with him: Thank you for your efforts to save him.

 

[Hetland]

Hello,

I am not a diver, but I knew Tim and his wife. I have been trying to find out what happened to him. I Google searched his name and found this thread. I have to say I have found more about what happened from this one thread than anywhere else. However, I have not been able to find the cause of death. Has anyone heard or read anything more?

For those that were on scene with him: Thank you for your efforts to save him.

I'm sorry for the loss of your friend.

As you may have gathered, Tim was diving with a device called a "rebreather". unlike scuba, where compressed air is supplied to the diver through a tank and a regulator, rebreathers recycle the diver's exhaled breaths to provide breathing gas. This is a much more complicated process than simple scuba, mainly because exhaled breath does not quite contain enough oxygen to sustain consciousness. A rebreather scrubs the divers exhalations of carbon dioxide, and adds supplemental gasses like oxygen when necessary. A rebreather, even in perfect working order, can deliver too much or too little of several different gasses to the diver's breathing supply. The result is that the diver could have a seizure, or simply go to sleep while underwater, both of which are almost always fatal. Tim's initial "event" could have been a gas issue as described above, or it could be as simple as a heart attack, stroke, or seizure, completely unrelated to diving. If the initial event was not directly fatal, then Tim likely died from one of two mechanisms. He either drowned from inhaling water, or he had a lung injury from being brought up from depth with a closed airway. Either way, Tim was gone by the time he was brought to the surface. I'm sure that Tim's dive buddies, and the Boat's Crew were fully aware of this, but they took life-saving measures anyway. It says a great deal about Tim and his buddies that they tried for so very long to bring him back against all odds. I can only guess that he was loved and cherished.

 

[twood]

Thank you for the information Hetland. Yes, Tim was loved by many. He was a great man.

 

[NoBreather]

Here is what I know:

• I was on the Oriskany during Tim's accident.
• I was diving with the same rebreather type at the time.
• I was not in Tim's party.
• The Down Under was tied off on the starboard side of the "island" slightly below and to starboard of the smoke stack. Our boat was tied off on the same spot.
• The current that day was very stiff. I live in Pensacola and dive and spearfish often (ave. 4-10 dives per month). The current was as strong as I have experienced in 7 years of diving off of Pensacola (with 30+ dives on the Oriskany). The current was also coming from the worst possible direction for Tim's dive; from bow to stern. Tim’s group had to swim directly into the current to reach the hanger deck from where the Down Under was tied off.
• Tim's group penetrated the hanger deck. The hanger deck is 165-180 feet deep.
• Tim was an experienced diver and in good shape.
• Tim was certified for normoxic trimix on the Inspiration unit he was diving.
• Tim's rebreather was rigged with shutoff valves on the demand value (diluent) and his "air-source" regulator/inflator. This is a common rig for tech rebreather drivers.

This is what I believe. Any of Tim's buddies on that dive can correct me:

• The strong current, and the direction of the current, were factor in the accident. I am in excellent shape and I was swimming has hard as I could just to maintain position. I spent most of the dive going hand-to-hand crawling along the ship.
  
• All divers in the group were using air as a diluent, not trimix.
  
• The two other divers did not have their rebreathers rigged with shut-off valves on the demand valve and inflator/regulator.

One possible scenario is:

1. The party was swimming hard against the current.
2. They swam toward the bow in order to enter the hanger bay via the elevator or around the port side of the flight deck.
3. Tim passed out from either a physical problem or CO2 build-up (breathing by his scrubber due to strenuous swimming against the current).
4. Tim's buddies did what they could. However, they may have been unfamiliar with Tim's shut-off values and may not have been able to use Tim's inflator.
5. The bloody froth is a bit of a mystery to me. My guess is that his airway was restricted during the assent.

These are educated guesses, not the facts. However, perhaps there is some food for thought/caution here for my fellow tech rebreather divers out there.

NB

"Inhale, exhale, rinse and repeat."