
Qantas Flight 72 uncommanded pitch-down manoeuvres - Stierlitz
https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Qantas_Flight_72<p>“Angle of attack (AOA) is a critically important flight parameter, and full-authority flight control systems, such as those equipping A330&#x2F;A340 aircraft, require accurate AOA data to function properly”.<p>“it was determined that the CPU of the ADIRU corrupted the angle of attack (AOA) data. The exact nature of the corruption was that the ADIRU CPU erroneously re-labelled the altitude data word so that the binary data that represented 37,012 (the altitude at the time of the incident) would represent an angle of attack of 50.625 degrees. The FCPC then processed the erroneously high AOA data, triggering the high-AOA protection mode, which sent a command to the electrical flight control system (EFCS) to pitch the nose down.”
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a3n
Why don't they just install a long enclosed ceramic channel down the length of
the plane, fill it with mineral oil and make the plane a really long bubble
level? As a backup?

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dbtx
Surely you know that gravitational force is indistinguishable from
acceleration and the idea of 'down' sensed by any mass inside the plane is the
vector sum of both.

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a3n
I surely do. And stop calling me Shirley.

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m463
At least they had 3 redunant ADIRU units.

Stuff like this has happened multiple times:

[https://en.wikipedia.org/wiki/Air_data_inertial_reference_un...](https://en.wikipedia.org/wiki/Air_data_inertial_reference_unit)

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kristianp
(2008)

