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by sebmellen 747 days ago
GPWS warnings should be the gold standard for any sort of urgent audio alarm.

Examples: https://www.youtube.com/watch?v=W5Z-d1Zx02o

4 comments

At :42 I think the buzzing sound is the "stick shaker" stall warning. It literally shakes the pilot's control yoke. So not only is it an alarm, it's also reminding the pilot of the correction needed: to push the control forward.
Wouldn't that be pull backward?
What i heard is that it is designed to imitate the stick sensation smaller airplanes have as the wind buffets the controll surfaces when a stall develops.

And pilots from an early stage in their flying training conditioned to push the stick forward when that happens.

Not in this case, because the 'stick shaker' activates when the aircraft is stalling or close to stalling. The only sensible option in this scenario is to lower the angle of attack, that is, pitch forward. If you have both the GPWS 'terrain, pull up' warning and the stick shaker warning simultaneously then you are in a sticky situation indeed.
> If you have both the GPWS 'terrain, pull up' warning and the stick shaker warning simultaneously then you are in a sticky situation indeed.

Yeah. To quote the movie Wargames: “The only winning move is not to play.” That is a pilot should do their best to avoid getting into anywhere near that situation.

I used to have pull up as my ringtone, freaked my uncle out (who's a commercial pilot) when he was over for dinners. Or at least he pretended to be :P
I was half-asleep travelling on a train when a kid blew a wistle near me which sounded exactly like the stall warning horn of the Cessna-150 i was learning to fly around that time. It jolted me awake right away. I had this clear clarity in my mind that i have to push the controls forward until i realised that I am nowhere near an airplane.
Making this my PagerDuty alert sound https://youtu.be/fbfVGIBcD8c?t=77