Originally Posted by
Rightbase
Logic errors can remain undetected in programmed systems for a long time.
The protocol of flying on with 'redundant' units defective is such a 'program' that by definition does not create an accident but equally obviously does erode safety margins.
When it is the integrity of the 'intelligence' between pilot and aircraft that is jeopardised by such a program it then puts at risk the strategy of having a human in ultimate control.
Programmer humility deficiency might be a common root cause.
I know that there is a wish to find an answer but this is not it.
Logic errors
can remain undetected - but this one
was detected the quotes are from an investigation into an event that was caused and an AD was very publicly issued to return to the previous version of the software.
So now are you really suggesting that Honeywell, having been told of the fault in their software in unequivocal terms,
forgot about it? Then over the 9 years since the incident that they have not updated the ADIRU software to fix the fault? To use a quote from tennis - You
cannot be serious.
And of course this ADIRU software fault would need to also disconnect ACARS and switch off all three redundant VHF radios incapacitate the crew
and then recover itself and fly the aircraft in uneventful cruise to the southern Indian Ocean.
Perhaps you would like to revisit your logic?