[greendot]

> 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.

That is a chilling statistic.

As a VFR pilot, I often wonder what would happen inside a cloud to make me react and rip my plane apart in under 3 minutes.

[0x12]

It's an average, you might do better.

Dramatized:

http://www.youtube.com/watch?v=fXzYZjpoz_E

[orborde]

That was very good. I couldn't deduce what was going on until the last moment, which is (I assume) exactly the experience of pilots in this situation.

[nknight]

I don't understand at all. It mentions compass and altimeter -- why the hell isn't the pilot looking at the artificial horizon?

[electromagnetic]

I think it's that so much of our orientation is dependent on peripheral vision. I know Canadas worst pile up was caused by a heavy fog. 87 vehicles piled up, they believe in a very short time from the fog rolling in. The main factor was speed, basically people were over driving their view distance. Visibility was estimated to be something like 50 meters, but driving at 110kph gives you a stopping distance of around 150 meters. What worsened the incident was that light fog generally reduces drivers speed, but heavy fog is known to increase speed as the lack of peripheral markers means people can't gauge their speed and too few drivers check their speedometer.

I'm sure a pilot in dense cloud has the potential to make a whole host of mistakes. First I'm sure without instrumentation a pilot would quickly lose gauge on how level they're flying, or second guess how level they're flying and try to adjust. If you get caught in a cloud with a very low ceiling, there's probably not much time between exiting the cloud and that "Oh shit, that stuffs the ground". Or a slight climb and not enough thrust could easily compromise your speed and put you into a stall.

I'm quite sure 3-dimensions of travel is a real bitch when you're blind and can't stop.

[ispolin]

Here is the fatal scenario: http://www.aerosafe.net/page6.html

As a VFR pilot, you've received basic instrument training. Remember that training, trust your instruments, and you'll make it though.

[electromagnetic]

With an altimeter, an artificial horizon and an airspeed indicator, you would expect a VFR pilot to be able to get through any light cloud safely.

Untrained, never having touched the cockpit of a plane, I can get the meaning from these instruments. Is it simply that pilots fly without these, or that they simply disregard them during flight?

[ispolin]

Neither. In US, your plane has to have the 6 basic instruments to be certified as airworthy by FAA. The reasons pilots die in non-visual flight conditions are twofold.

As the original article pointed out, the first reason is that the sensations are so compelling that doing what the instruments tell you will feel VERY unnatural and you will keep thinking that your instruments are broken or stuck (hence you HAVE to trust your instruments). And even if you remember not to trust your instincts, you will still often unconsciously apply slight pressure to the controls.

The second reason is that for every change in the plane's orientation and speed, several instruments will start moving at once. Without training it is very hard to integrate what the 6 instruments are telling you into a complete mental picture of what's going on with your airplane.

[vacri]

Ah, it's from a simulator, where you don't get the benefit of your own body responses - no inner ear cues, no tactile feedback, no proprioception feedback.

People driving cars in simulators also do worse than in the real thing - a simulated car doesn't have all the ways a car tells you that you're driving close to the envelope.

[ispolin]

Not exactly. "Simulated Instrument Flight Conditions" usually means that your instructor has you put on a view limiting device [1] so that you can only see your instruments and not outside the aircraft.

One of the reasons it's done this way is to teach you to ignore inter ear cues and trust your instruments. Your inter ear senses acceleration, not absolute motion. Couple that with the centrifugal force during a turn changing your perception of which way "down" is, and your body responses become one of the main reasons you get into trouble.

It's similar to banked turns on car racetracks. When you're in a banked turn, "Down" for you is no longer towards the center of the earth, it's at an angle, perpendicular to the speedway. You also loose the sensation of turning once you're in that banked turn long enough (specifically once the fluid in your ear settles down and stops moving). If you were driving with a blindfold, you wouldn't be able to feel how steep your turn was.

[1]: http://sportys.com/pilotshop/category/864 "View Limiting Devices"

[vacri]

Thanks for the info - I was unaware of those devices.

I guess what I was getting at was not so much that you could survive with your inner ear, but that you get a lot of feedback from a vehicle that you don't in a simulator. That's not relevant to this study if they didn't use a simulator, though...

[omegant]

Usually what will happen is that you'll think you are still flying straight but a small roll and dive will be happening, when you come out of the clouds you'll be in a very deep dive and/or almost inverted. If you don't have enough altitude to recover, you are done.

[vacri]

Perhaps it is eaten by a grue?