drugs and flying common in GA?

[Dave Krall CFII]

So when your friend was landing on the water, do you think he was suffering from the effects of hypoxia?

Good question.
BTW: Only just knew of him, through the WSPA and unfortunately, subsequent aviation magazine write-ups he did in an attempt to help others possibly avoid similar tragedies.

Regarding possible hypoxia, as I recall, the lake itself was virtually at sea level. The hours flying just prior to that accident, I don't know what altitude they were averaging at. Enough time has passed, and he has put so much painful effort into education that maybe I will either ask him, or others that might know that information.

 

[SteveinIndy]

So when your friend was landing on the water, do you think he was suffering from the effects of hypoxia?

As I pointed out in my original posts, it is still somewhat unclear how long the mental effects of low-grade hypoxia persist after the "technical" hypoxia is corrected. ("Look at the pulse ox! My numbers are normal!"). The FAA isn't prone to updating or openly questioning its medical standards until you wind up with something either catastrophic or involving someone well connected or famous happens as a result of bad information.

 

[Henning]

As I pointed out in my original posts, it is still somewhat unclear how long the mental effects of low-grade hypoxia persist after the "technical" hypoxia is corrected. ("Look at the pulse ox! My numbers are normal!"). The FAA isn't prone to updating or openly questioning its medical standards until you wind up with something either catastrophic or involving someone well connected or famous happens as a result of bad information.

All the tests we did with it had the effects going away almost instantly as PPO2 cam into a .16 and above range; caveat: we were doing the experiments with hypoxic gas mixes in a diving environment.

 

[Dave Krall CFII]

All the tests we did with it had the effects going away almost instantly as PPO2 cam into a .16 and above range; caveat: we were doing the experiments with hypoxic gas mixes in a diving environment.

This touches on another facet of this realm, which is the cognitive requirements of any particular activity in question besides the flying mentioned the OP, in your example diving, others have mentioned skiing and sky diving.

I don't know where various levels of diving would fall on a scale rating cognitive requirements but, I estimate double diamond grade skiing and deep diving to still be not quite as demanding as PIC time.

 

[Henning]

This touches on another facet of this realm, which is the cognitive requirements of any particular activity in question besides the flying mentioned the OP, in your example diving, others have mentioned skiing and sky diving.

I don't know where various levels of diving would fall on a scale rating cognitive requirements but, I estimate double diamond grade skiing and deep diving to still be not quite as demanding as PIC time.

We were doing math problems and card matching games as a measure of cognitive function.

 

[Dave Krall CFII]

We were doing math problems and card matching games as a measure of cognitive function.

IF flying a small plane as PIC into above average demands is rated about 7 or 8 out of 10 MAX in degree of physiocognitive difficulty, what rating would you and others estimate various potentially dangerous activities?

 

[Henning]

IF flying a small plane as PIC into above average demands is rated about 7 or 8 out of 10 MAX in degree of physiocognitive difficulty, what rating would you and others estimate various potentially dangerous activities?

Silt out off your extraction line in a wreck or cave then having to recalculate your deco commitment to an unplanned profile while swimming out low on gas and possibly dealing with some nitrogen narcosis? 9.97.

 

[Dave Krall CFII]

Silt out off your extraction line in a wreck or cave then having to recalculate your deco commitment to an unplanned profile while swimming out low on gas and possibly dealing with some nitrogen narcosis? 9.97.

That's much higher than I would have guessed. These recalcs and unplanned diving profiles, are they performed solely by a single diver or as a team effort with ground personnel and/or other divers?

The rating should reflect degree of difficulty BEFORE any biophysical impairments take effect.

 

[Alexb2000]

That's much higher than I would have guessed. These recalcs and unplanned diving profiles, are they performed solely by a single diver or as a team effort with ground personnel and/or other divers?

I don't see the correlation between nitrogen narcosis and endorphins in terms of affecting someones ability or judgement flying an airplane.

The diving effects are quantifiable, measurable, and consistent. Henning may (I don't know) also be talking about commercial diving on try-mix or nitrox or some gas makeup unlike our atmosphere which would also be diving specific.

 

[Dave Krall CFII]

I don't see the correlation between nitrogen narcosis and endorphins in terms of affecting someones ability or judgement flying an airplane.

The diving effects are quantifiable, measurable, and consistent. Henning may (I don't know) also be talking about commercial diving on try-mix or nitrox or some gas makeup unlike our atmosphere which would also be diving specific.

I further qualified the ratings criteria in an edit while you replied.

 

[Henning]

That's much higher than I would have guessed. These recalcs and unplanned diving profiles, are they performed solely by a single diver or as a team effort with ground personnel and/or other divers?

The rating should reflect degree of difficulty BEFORE any biophysical impairments take effect.

Every man on the team is solo as far as that goes, then when finished, you have to figure your buddy's requirements against what you have left to make sure that you can still meet your new deco requirements combined on each individuals residual gas, if not, you have to calculate what the best deco profile you can get away with is and if you'll need a ride to the chamber when you surface. This all has to be done with no verbal communication. Diving 300' in an overhead environment, both physical (wreck and/or cave) and virtual (deco commitment) overheads on mixed gasses is a whole different game than scuby-doo diving in open water with a dive computer on your wrist. When things go wrong, there is a whole lot of thinking and calculating involved. The good thing is typically you only deal with hypoxic PPO2s near the surface if you are still on your bottom mix, and by then you should have most of the math worked out. Still gets stressfull though and Nitrogen Narcosis at depth (we always run some as if you use too much Helium you run into potential HPNS issues) has a more debilitating effect than hypoxia. Then when you are pushing your deco, you have O2 CNS hit considerations.

 

[SteveinIndy]

All the tests we did with it had the effects going away almost instantly as PPO2 cam into a .16 and above range; caveat: we were doing the experiments with hypoxic gas mixes in a diving environment.

With flying it's a bit more complicated...or could be theoretically since you're dealing with reduced partial pressures and the effects thereof which can include altered pulmonary physiology such as vascular derangement (vasoconstriction or dilation causing shunting) and mild pulmonary edema. I recall some data in the high altitude physiology literature that you can start getting these effects, albeit normally subtly, in non-acclimated folks at 6,000 ft AMSL.

My other concerns is that you're talking (when it comes to tech divers) about a normally much more fit group than your average GA pilot population (any group that sees greasy diner food as an excuse to travel needs to be treated as suspect so far as physical fitness is concerned). One of the lingering effects of hypoxia that is pretty well established is accelerated onset of fatigue. That alone could potentially explain some of the "stupid" mistakes we see in pilot regarding fuel management, VFR into IMC, CFIT or failure to extend gear on final. My question as a scientist is whether the fatigue is the effect of delayed clearance of products of metabolism such as lactate and pyruvate as occurs in distance runners.

Diving 300' in an overhead environment, both physical (wreck and/or cave) and virtual (deco commitment) overheads on mixed gasses is a whole different game than scuby-doo diving in open water with a dive computer on your wrist.

A friend of mine who is a retired technical diver and now a very active commercial pilot used the analogy that tech diving is to recreational scuba diving what flying to ILS minima is to a private pilot doing some severe clear VFR flying. His comment was that the mindsets have to be completely different in terms of preparation and operational execution and the failure of a large swath of the GA pilot population to see that explains why we end up identifying an unnecessary number of pilots by their dental records each year.

The analogy came about as the result of a conversation regarding how I never fully trust a dive computer. I regard it with the "trust but verify" approach. Then again, I also do a deco stop even from theoretical no-decompression limits. I figure it gives me a few more minutes to enjoy being underwater before I have to start dealing with people (beyond my dive buddy) again. That said, I never had the desire to do mixed gas diving other than using a nitrox during recreational stuff.

 

[docmirror]

I don't know where various levels of diving would fall on a scale rating cognitive requirements but, I estimate double diamond grade skiing and deep diving to still be not quite as demanding as PIC time.

Bull-puckey. Grab your skis and come on up to Breck this winter. You have no idea what super-G or GS skiing requires. I'm also a diver, and in that case, it requires moderate cognition, but luckily everything happens in slow motion, as if you were incased in -- water. haha

My statement on the affects of euphoria were constrained by no hypoxia which is a known factor for those at altitude. If he had hypoxia, then that is a discrete issue not related to your original thesis on some kind of latent loss of responsible pilotage due to feeling too good. As noted, hypoxia clears up rapidly once the person is given enough oxygen to think right.

 

[Dave Krall CFII]

Bull-puckey. Grab your skis and come on up to Breck this winter. You have no idea what super-G or GS skiing requires. I'm also a diver, and in that case, it requires moderate cognition, but luckily everything happens in slow motion, as if you were incased in -- water. haha

My statement on the affects of euphoria were constrained by no hypoxia which is a known factor for those at altitude. If he had hypoxia, then that is a discrete issue not related to your original thesis on some kind of latent loss of responsible pilotage due to feeling too good. As noted, hypoxia clears up rapidly once the person is given enough oxygen to think right.

As far as snow skiing goes, my estimates were from 20 years of doing it at difficult levels and high altitudes, including Breckinridge way back in the Dark Ages. Maybe it's grown higher and steeper since then.

Big difference between skiing and flying is the actual physical requirement of skiing is much higher, the cognitive for flying is much higher. Probably doesn't mean much to compare activity degrees of difficulty and cognitive ability, it was just a thought.

 

[Everskyward]

As far as snow skiing goes, my estimates were from 20 years of doing it at difficult levels and high altitudes, including Breckinridge way back in the Dark Ages. Maybe it's grown higher and steeper since then.

Big difference between skiing and flying is the actual physical requirement of skiing is much higher, the cognitive for flying is much higher. Probably doesn't mean much to compare activity degrees of difficulty and cognitive ability, it was just a thought.

I think it's difficult to compare activities because it's hard to tell if someone is equally trained and current.

 

[Dave Krall CFII]

I think it's difficult to compare activities because it's hard to tell if someone is equally trained and current.

Exactly.
Even in the same activity there are so many uncontrollable variables, both mental and physical.
__________________
Flying, flight instruction, STOL Amphibion design and flight testing for the noblest of all reasons: Because It Is Cool

 

[Henning]

I think it's difficult to compare activities because it's hard to tell if someone is equally trained and current.

No kidding, I'm way more likely to get myself killed skiing vs flying.

 

[ClimbnSink]

Skiing fast has far more decisions per second then flying. And the perception, true or not, is of being closer to pain when skiing.

As far as snow skiing goes, my estimates were from 20 years of doing it at difficult levels and high altitudes, including Breckinridge way back in the Dark Ages. Maybe it's grown higher and steeper since then.

Big difference between skiing and flying is the actual physical requirement of skiing is much higher, the cognitive for flying is much higher. Probably doesn't mean much to compare activity degrees of difficulty and cognitive ability, it was just a thought.

 

[Dave Krall CFII]

Skiing fast has far more decisions per second then flying. And the perception, true or not, is of being closer to pain when skiing.

Granted but, they are much simpler decisions, and of a much smaller set of options, unless you're skiing in an aircraft!
__________________
Flying, flight instruction, STOL Amphibion design and flight testing for the noblest of all reasons: Because It Is Cool

 

[Jaybird180]

As a non-current trackday motorcyclist I realize that there are 11 possible control inputs I can make with a motorcycle. With a simple airplane like a C172 there are 10 possible control inputs. Sense of speed on a bike is accelerated comparatively; airplanes move slowly. The mental workout during a flight is high at the beginning and end and a lull during cruise. Only lull in mental activity during a session is if you have a long enough straight, then you're thinking about your braking zone.

I think it depends upon one's proficiency level. There are times where the bike ceased to be beneath me and it was me vs the track. Other times, the bike was working me so much that I couldn't focus on the track. The airplane is never like this.