PPRuNe Forums - View Single Post - Boeing 737 Max Software Fixes Due to Lion Air Crash Delayed
Old 25th Mar 2019, 13:42
  #380 (permalink)  
alf5071h
 
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The Further to the suppositions at # 365, 376 and also by Loose rivets. Ethiopian airliner down in Africa

Would the software view - ‘bits’, check sum error (?), A to D conversation (?), apply to the following:-

Why the AoA value failed high - both Lion flights, Ethiopian assumed based on outcome.

That the offset could be reset with aircraft power-down, or WoW alternate switching, or Maintenance system self-test (explanations for having the maintenance log recording a fault, but none clearly identifiable by engineers or flight crew before the next flight.)

Would such a ‘failure’ be a random, probabilistic occurrence - just chance, or require an external disturbance - elect spike (FDR AoA error seen during taxi - generator switching? Lion FDRs indeterminate, Ethiopian unknown.)

Caution; however good a theory might be, it would have to match all available information (wait for Ethiopian FDR), and in scientific terms be repeatable elsewhere, thus providing a basis for modification.

Related links:-
https://www.satcom.guru/2019/03/ethi...s-to-lion.html
https://www.satcom.guru/2018/12/angl...ure-modes.html




Last edited by alf5071h; 25th Mar 2019 at 14:40. Reason: Typo
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