Originally Posted by
PEI_3721
A number of interesting topics in that article.
One which seems to have been half-forgotten recently amid the safety oriented discussions (it was discussed in the prior threads), is what function the revised MCAS actually serves, given its limited scope:
Returning to MCAS, I will try to solve a mystery. Since Boeing announced that they will limit the authority of MCAS, how is it going to cope with real high Angle-of-Attack situations? What justified such a forceful reaction of MCAS initially? Another mystery of the MCAS design is the 10 seconds on - 5 seconds off logic, using aerodynamic feedback only, based on a single A-o-A sensor only.
And a related and more profound theme:
In our opinion, a FBW aircraft requires a separate certification process, even though it is aerodynamically identical to a classic aircraft. Also, a non FBW aircraft which includes at least one augmentation system which takes over and cannot be switched off, such as the MCAS, becomes a de facto FBW aircraft. This species could be called Sometimes-Fly-By-Wire (SFBW). However, the presence on board of an automated decision maker, totally changes the processes and the culture in the cockpit. Boeing 737 pilots were not prepared for that change.