4 ms·

The old vacuum attitude indicators have a tendency to fail in a really slow and subtle way as the gyro slows down. Yet, there are other instruments in the cabin

by lsh123 14y ago

The old vacuum attitude indicators have a tendency to fail in a really slow and subtle way as the gyro slows down. Yet, there are other instruments in the cabin to figure this out. There are rules of how to detect failed or unreliable indicators. It would be really hard (read: impossible) for an attacker to fake all instruments together to show a believable picture. AF447 crash was caused by not following the procedures for the loss of airspeed reading followed by lack of basic manual flying skills (e.g. complete inability to fly the plane at high altitude w/o autopilot). Read the final report, it's not about instruments, it's about pilots.

jnsaff2 14y ago
I did read the report and disagree with you. The pilots where inexperienced being in a violent thunderstorm with computers giving intermittent false information. There were no outside visual references. It was a complex set of circumstances that converged. I have a pilots license and I agree that sitting on a couch, reading the report in retrospective there were cues that could have been interpreted differently, there were procedures that should have been followed more directly and other things that could have been done to prevent oneself to get into this kind of mess in the first place. BUT. Would I have performed better in the same position? I don't know. Reading crash reports is for educating oneself so you can perform better in the next sticky situation or spot problems a mile away. Can this attack in the original article crash airplanes alone today? Definite no. Can it be evolved to play a part in some other foul play sometime in the future? I would not underestimate the inventiveness of people.
- lsh123 14y ago
  I personally had a frozen pitot tube due to failed tube heating in the solid IMC (no thunderstorm though). You just disable autopilot and manually fly by the known manifold pressure numbers, vertical speed and attitude. Plus double check with GPS ground speed (estimating the wind). This is not even an emergency (you have to advise ATC about the situation though). Things fail all the time. This is why there is redundancy built into the system. A pilot just need to know how to detect the problem and how to use secondary systems.

by lsh123 14y ago

jnsaff2 14y ago

I did read the report and disagree with you. The pilots where inexperienced being in a violent thunderstorm with computers giving intermittent false information. There were no outside visual references. It was a complex set of circumstances that converged. I have a pilots license and I agree that sitting on a couch, reading the report in retrospective there were cues that could have been interpreted differently, there were procedures that should have been followed more directly and other things that could have been done to prevent oneself to get into this kind of mess in the first place. BUT. Would I have performed better in the same position? I don't know. Reading crash reports is for educating oneself so you can perform better in the next sticky situation or spot problems a mile away. Can this attack in the original article crash airplanes alone today? Definite no. Can it be evolved to play a part in some other foul play sometime in the future? I would not underestimate the inventiveness of people.

lsh123 14y ago
I personally had a frozen pitot tube due to failed tube heating in the solid IMC (no thunderstorm though). You just disable autopilot and manually fly by the known manifold pressure numbers, vertical speed and attitude. Plus double check with GPS ground speed (estimating the wind). This is not even an emergency (you have to advise ATC about the situation though). Things fail all the time. This is why there is redundancy built into the system. A pilot just need to know how to detect the problem and how to use secondary systems.