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enter image description here

There is that thing I have see a few pilot using it. it can be pulled outside and then inside. what's that and what's the use of it?

Notts90
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Mamad
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1 Answers1

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That's where the analogue/backup compass is stowed. The compartment can be opened downward if you ever need to use the compass, as seen in this image:

enter image description here

60levelchange
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    Why is it designed to be stowable? It doesn't seem to impede cockpit visibility when deployed, and surely the stowing mechanism adds at least a little bit of weight and cost. Is it just for aesthetic reasons? – David Dec 08 '19 at 19:31
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    @David Just a guess, but I suspect that Airbus management was embarrassed to put such a low tech instrument into their most advanced cockpit. So they decided to hide it after pilots refused to fly without. – Peter Kämpf Dec 08 '19 at 21:02
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    @PeterKämpf It likely would not have passed FAA certification without one, though. It's standard equipment required on any aircraft. – Tyzoid Dec 08 '19 at 21:09
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    Being stow-able means less likelihood of accidental damage (which, as its probably on the MEL is quite significant), you can turn the light off unless its in its open position etc etc etc. – Moo Dec 09 '19 at 00:26
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    I believe the Airbus terminology for this guy is standby compass, but the description as a backup/analogue compass is accurate. – verandaguy Dec 09 '19 at 15:10
  • Would it be worth its own question to ask why such an instrument wasn't designed to be always visible and the expectation of comparing it with the digital system built into standard procedures? – TheLuckless Dec 09 '19 at 17:42
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    @TheLuckless: likely because the main failure mode for a primary digital compass is display failure, not inaccuracy. It's a pretty simple system all things considered. – verandaguy Dec 09 '19 at 18:16