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Why do pilots still die from not knowing which end is up?

airspacemag.com

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Re: Why do pilots still die from not knowing which end is up?

#11

Post by mechanical_fish »

bwooceli wrote: post #2

Good article, but I am a bit confused about how someone in 1906 (2nd page, top paragraph) supposedly did research on vestibular effects on pilots...

This article includes a statistic so scary that I'm going to have to fight the urge to paste it twice:

According to a 2004 study, the average life expectancy of a non-instrument-rated pilot who flies into clouds or instrument conditions is 178 seconds.

At that rate, I'd imagine it didn't take long after the first plane flight for pilots to notice that there was a big problem with, say, closing your eyes or otherwise getting distracted while flying. Or perhaps a pilot or two tried flying into a cloud -- it's the sort of thing you'd try to do if you could, right? -- and their remaining colleagues then started wondering why flying into clouds was such a sure-fire way to die. Death sure does have a way of crystallizing such questions.

The other point I'd make is that fixed-wing aircraft research probably had obvious potential military applications even in the prewar age of 1906. Perhaps this research was funded so early for much the same reason that astronaut-physiology research was well funded even before the first astronaut reached low-earth orbit.

Re: Why do pilots still die from not knowing which end is up?

#12

Post by 0x12 »

biot wrote: post #5

I've had a similar experience while driving on a highway at night in foggy conditions. All of a sudden my car started slowing down and was rapidly losing power. I checked and it wasn't fuel, so I figured the engine was dying somehow. It wasn't until I tried gearing down that I realized I had been on a steep hill and fifth gear wasn't powerful enough. But even afterward, I couldn't sense that I was on an incline.

I have a simple trick for that: I know the consumption of my car on a level road in 5th gear at 90 km/h, so when I'm in doubt about whether or not I'm going up, down or level I look at the fuel consumption indicator.

If it is higher than 6.6L/100km then I'm going up, less is down.

If you don't have a fuel consumption indicator then that will not work but lots of cars have them these days and I think using them as a level is a useful unintended application.

Re: Why do pilots still die from not knowing which end is up?

#13

Post by 7952 »

3pt14159 wrote: post #6

How are there not heads up systems that detect this? A simple "warning 5 seconds to impact with the ocean" would at least warn the pilot.

But it would still require action from a pilot, who is known to be disorientated, and probably quite upset about their imminent collision with the ocean.

Perhaps an alternative would be to use a belt that vibrates differently depending on the angle of the aircraft. Humans are good at integrating data without conscious thought. This has been used with compass direction on the ground to dramatically improve spatial awareness without any conscious effort http://www.wired.com/wired/archive/15.04/esp.html.

Re: Why do pilots still die from not knowing which end is up?

#14

Post by apaprocki »

mynameishere wrote: post #8
3pt14159 wrote: post #6

How are there not heads up systems that detect this? A simple "warning 5 seconds to impact with the ocean" would at least warn the pilot.

Even little planes have those. What they need is a switch to tell the computer that they expect no descent whatsoever below xy000 feet, to stop it before it starts. You can hear that warning here http://www.youtube.com/watch?v=SjaU-SKYrPk http://www.youtube.com/watch?v=LzDSq6m2zV4

I was going to suggest this in my post. A "dead-man"'s limit. A plane would lock you out and right itself it detected you dropped below some pre-defined altitude (e.g. within an acceptable angle without landing gear deployed or a greater than acceptable angle with or without landing gear deployed). Whatever altitude is necessary for the plane to right itself from the steepest descent. Something like that would make it impossible for someone to storm a cockpit and nose-dive a plane. It would need appropriate remote electronic and mechanical overrides, though to prevent possibly losing a plane if it was triggered incorrectly. But at least a plane flying level on lockout autopilot would buy some time opposed to it definitely being destroyed by the nose-dive.

Re: Why do pilots still die from not knowing which end is up?

#15

Post by mkr-hn »

0x12 wrote: post #12
biot wrote: post #5

I've had a similar experience while driving on a highway at night in foggy conditions. All of a sudden my car started slowing down and was rapidly losing power. I checked and it wasn't fuel, so I figured the engine was dying somehow. It wasn't until I tried gearing down that I realized I had been on a steep hill and fifth gear wasn't powerful enough. But even afterward, I couldn't sense that I was on an incline.

I have a simple trick for that: I know the consumption of my car on a level road in 5th gear at 90 km/h, so when I'm in doubt about whether or not I'm going up, down or level I look at the fuel consumption indicator. If it is higher than 6.6L/100km then I'm going up, less is down. If you don't have a fuel consumption indicator then that will not work but lots of cars have them these days and I think using them as a l…

This is the first I've heard of fuel consumption indicators. What kind of car is it?

Re: Why do pilots still die from not knowing which end is up?

#16

Post by 0x12 »

apaprocki wrote: post #10

Given the analysis of what happened in the recent Air France crash, I can't imagine why the industry does not write better software to help combat this. It seems as if the programmers writing the software are more concerned about writing valid code to fit the designed system ("the pilot signaled us to climb at exactly 40 degrees, so do it") rather than writing code that models the real world situations accurately. I…

What the pilot will do to keep the passenger and plane safe can't be foretold by software written in static situations on terra firma.

Sensors can lie, equipment can break. Your software may have no better idea of the true situation than the pilot.

In the end it is a judgment call and if you limit the ability of those judgment calls to a bunch of software then you are saying that those in a different time and place have a better idea of what to do than those with their feet in the dirt.

It looks like in this case someone made the wrong judgment call. False positives in warning systems in commercial aircraft are happening with some regularity, in the end the pilot has final say.

Re: Why do pilots still die from not knowing which end is up?

#18

Post by 0x12 »

mkr-hn wrote: post #15
0x12 wrote: post #12

Earlier quoted context omitted.

I have a simple trick for that: I know the consumption of my car on a level road in 5th gear at 90 km/h, so when I'm in doubt about whether or not I'm going up, down or level I look at the fuel consumption indicator. If it is higher than 6.6L/100km then I'm going up, less is down. If you don't have a fuel consumption indicator then that will not work but lots of cars have them these days and I think using them as a l…

This is the first I've heard of fuel consumption indicators. What kind of car is it?

Citroen C8/Peugeot 807 (same car, different badge). It's built into the trip computer.

Re: Why do pilots still die from not knowing which end is up?

#19

Post by apaprocki »

0x12 wrote: post #12
biot wrote: post #5

I've had a similar experience while driving on a highway at night in foggy conditions. All of a sudden my car started slowing down and was rapidly losing power. I checked and it wasn't fuel, so I figured the engine was dying somehow. It wasn't until I tried gearing down that I realized I had been on a steep hill and fifth gear wasn't powerful enough. But even afterward, I couldn't sense that I was on an incline.

I have a simple trick for that: I know the consumption of my car on a level road in 5th gear at 90 km/h, so when I'm in doubt about whether or not I'm going up, down or level I look at the fuel consumption indicator. If it is higher than 6.6L/100km then I'm going up, less is down. If you don't have a fuel consumption indicator then that will not work but lots of cars have them these days and I think using them as a l…

Another trick might be using star alignment. A fixed position camera on the top of the plane could sense pitch by tracking which stars are in view. Or similarly, if you boxed a sensitive GPS receiver so that it could not detect signals from the sides, the satellite IDs which are in view could possibly indicate alignment of the plane as well. The best model would tie in as many observations as possible to maximize the probability that it is right.

EDIT: What about fuel sensors in the wing? If the computer knew the volume of the remaining fuel and the altitude was not dropping, it could determine the orientation of the plane if there were sensors inside the tanks to detect which were submerged.

Re: Why do pilots still die from not knowing which end is up?

#20

Post by apaprocki »

0x12 wrote: post #16
apaprocki wrote: post #10

Given the analysis of what happened in the recent Air France crash, I can't imagine why the industry does not write better software to help combat this. It seems as if the programmers writing the software are more concerned about writing valid code to fit the designed system ("the pilot signaled us to climb at exactly 40 degrees, so do it") rather than writing code that models the real world situations accurately. I…

What the pilot will do to keep the passenger and plane safe can't be foretold by software written in static situations on terra firma. Sensors can lie, equipment can break. Your software may have no better idea of the true situation than the pilot. In the end it is a judgment call and if you limit the ability of those judgment calls to a bunch of software then you are saying that those in a different time and place h…

I think a more robust model of N completely different systems (both mechanical and electrical) to compute the same variable could be found so that the probability that it is computing a value outside of x% of the actual real value is lower than the probability that the human could make a mistake. Even if a speed indicator model in the event of pitot tube loss had a 25% margin of error, autopilot could have done the right thing or it could have possibly influenced their decision to pull back.

EDIT: You can down-vote, but this is already the direction that cars have gone. For example, there is no way to stop any Mercedes after 2009 from automatically applying full brakes in an impending collision.

http://www.daimler.com/dccom/0-5-1210220-1-1210348-1-0-0-121...

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