The computer errors from outer space
&gt; In one much-discussed incident, a 2008 Air Qantas flight over Western Australia fell hundreds of feet twice within 10 minutes, injuring dozens of passengers on board<p>This was Qantas Flight 72 [1] and should be of interest to all critical system engineers.<p>There was a fault, an unidentified cause that corrupted data in ONE of three redundant Air Data Inertial Reference Unit (ADIRU)s.<p>The fault might have been a cosmic ray incident, it may have been EM interference, the usual array of software bugs, software corruption, hardware faults, etc.<p>The serious design issue was the spike in one unit was badly and incorrectly handled by the &quot;failsafe&quot; logic that was there to ride out bad juju coming from one of three redundant units.<p>Shit happens, its nice to have toilet paper thats effective when things are about to hit a fan.<p>[1] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Qantas_Flight_72" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Qantas_Flight_72</a><p>Full Air Safety Report (313 pages)<p><a href="https:&#x2F;&#x2F;www.atsb.gov.au&#x2F;media&#x2F;3532398&#x2F;ao2008070.pdf" rel="nofollow">https:&#x2F;&#x2F;www.atsb.gov.au&#x2F;media&#x2F;3532398&#x2F;ao2008070.pdf</a>