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When an A330/40 is in alternate law1 and approaching a stall, it has a stall warning composed entirely of a cricket chirp and a voice saying "stall, stall". Most other aircraft, in contrast, have a stickshaker, which vibrates the stick when the aircraft approaches a stall.

Pilots are, as demonstrated by numerous crashes, very (very very) good at tuning out aural warnings, whereas a stickshaker provides a powerful tactile cue that is very difficult to ignore; so why doesn't the A330/40 have a stickshaker?

1: In normal law, the A330/40 has no stall warning, as its automatic angle-of-attack protections supposedly make it impossible to stall the aircraft by pulling on the stick.

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    $\begingroup$ Stall warning operates independently from the high-AOA protection and does sound in normal law. This would happen in highly dynamic situation where alpha/speed variations are large, especially when operating close to maximum weight. $\endgroup$ – busdriver Apr 20 at 4:09
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    $\begingroup$ Without any knowledge about certification of the sidestick controller, I would speculate that shaking the controller would hamper the controllability and disturb the movements on the sidestick. The range of motion on the sidestick is much smaller than on conventional yoke and required deflections are often so small that shaker would actually prevent accurate flying in the critical moment. $\endgroup$ – busdriver Apr 20 at 4:32
  • $\begingroup$ On Airbus aural warnings can’t be switched off $\endgroup$ – user40476 May 28 at 17:21
  • $\begingroup$ @user40476: I said tuning out, not turning off. $\endgroup$ – Sean May 29 at 0:56
  • $\begingroup$ Sorry, thank you, but you can’t ignore the STALL aural alarm it’s so loudly. Further the stick displacement is very narrow compared to a yoke, a stick shaker will produce oscillating inputs to the stick transducers. $\endgroup$ – user40476 May 30 at 10:13

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