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Old 22nd Mar 2019, 05:11
  #2313 (permalink)  
dinbangkok
 
Join Date: Nov 2005
Location: London
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Originally Posted by Rananim
Hard not to concur.A lot of Boeing bashing going on here.
Life isnt black and white like that.
Its not all Boeings fault.Its not all the pilots fault for not cutting out those 2 switches.
I think it was mentioned by FCENG84 that designers design safe
in the knowledge that airline pilots have a minimum standard
of airmanship and that line engineers know their job and
follow the MEL.Lionair's reputation is not a good one.
And frankly speaking,neither is Ethiopian.So its a difficult.situation
to analyse.Do I think either accident could have
happened in Southwest?No,I do not.

Boeing obviously considered the consequences of a faulty
sensor and its effect on MCAS prior certification.They knew
this would occur at flap retraction at low altitude and would result
in stick shaker,unreliable airspeed and considerable and
unexpected nose down trim all at once.They decided
that this failure scenario was one step shy of "catastrophic".
and that a crew would cope.Maybe they under-rated the
effect of the stick shaker on the pilots ability to react in the
correct manner.Those shakers can scramble your brain
and degrade reaction time and pilot response.They can cause
startle factor which I know is sometimes derided as an
excuse for poor airmanship.But it can happen and it can affect
quite a few crews.
Whats not okay is if they deliberately downgraded it below
"catastrophic" to rush certification and avoid further analysis
and fine-tuning of the design.If they genuinely miscalculated
the effect of unwanted MCAS at low altitude and so designed
it to work off one sensor only,then its just an error.
However,if they downgraded it below "catastrophic" to rush
certification then it was a cynical decision and thats negligence.
Regardless of whether you're a pilot or not, surely the question that needs to be answered is simple: How is it remotely OK for Boeing (or any other manufacturer), to sell a passenger aircraft that needs software to correct an aerodynamic imbalance in the design of the aircraft (prone to pitching up)?
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