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Old 3rd Apr 2019, 16:14
  #2983 (permalink)  
patplan
 
Join Date: Nov 2018
Location: Vancouver
Posts: 67
Originally Posted by ManaAdaSystem View Post
How is this possible? MCAS is still operational with the trim system disabled????
If this is true Boeing not only designed the MCAS system and installed it without telling the pilots, but they also failed to tell pilots it canít be switched off, even after Lion Air crashed?
They made a procedure to deal with a runaway MCAS that is completely worthless and will not take care of the problem?
Hence, this might be the reason for the delay in releasing the preliminary report.

Apparently, according to WSJ, there were disagreements between investigators about how to interpret the FDR [& CVR] data.

...Safety experts have also tussled over the interpretation of certain data and their presentation in the report, according to people from both countries...
The major news is that MCAS was turning back on after being shutoff as per NNC for Runaway Trim. The question becomes why was it back on? There are two conflicting news coming out. The first version suggested that the crew had turned the stab trim motor back on because they'd had some difficulty to trim the AC manually, essentially going against the NNC procedure. And, the other version of the news reported that the MCAS system was turning back on by itself, suggesting there was yet another unknown/undocumented power mechanism in the Max-8 coming into play.

We can safely guess now that the disagreement between investigators mainly must have been about what/who turned the MCAS back on.

Personally, I think it is doubtful that MCAS really have another route to power up its trim. Unless, it had metamorphosed itself into a franken-system, unbeknownst to us all.
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