Originally Posted by
MechEngr
Quite a few of the astonishing items in that article are false. But it is written as a Gish Gallop, so an equally lengthy response is required to debunk them.
Example: That the 737 MAX was unstable and MCAS corrects that instability. So far, all facts point to False. The 737 Max is stable and MCAS is not needed to correct instability. There are many others, but since it starts off with misinformation, it is not a good sign.
My emphasis.
Based mainly on the views expressed by others on pprune:
what facts? (Genuine question)
a) Boeing have gone to great lengths to deny instability. As far as I am aware they have not supplied any data to support the claim. There is no requirement for them to do so in the public domain, and commercial confidentiality may be involved.
b) Several certifying authorities may have explored stability. They aren't publishing the results, and possibly have an obligation not to.
c) A stable aircraft may be uncertifiable because of "feel" requirements. It seems possible that MCAS was introduced to address this issue. I cannot remember if B has commented on this.
d) MCAS looks awfully like a flight-envelop-restriction mechanism rather than a feel-augmentation one. Which doesn't make it an inappropriate way to meet the certification requirements.
So to an interested observer this looks like a factual vacuum -- at least in the public domain.
PS
At first sight I'm not too impressed with the article either (or the preceding software view paper).