Originally Posted by
ASH26E
I wonder what the FAA and EASA will make of the recent Lion Air 737 Max event resulting from the failure of a single AoA sensor in the light of 25.901(c)
To add a bit to what Luc Lion posted, 25.901(c) is specific to propulsion systems - not flight controls (which have their own set of applicable regulations).
No question if TCMA was the cause of the dual shutdown then there is an issue that needs to addressed in the software. There is a quite comprehensive review of the TCMA limits during the flight test program (at least on the 747-8, we had TCMA deactivated for much of the flight test program, until we had enough real engine data to verify we had adequate margins between the TMCA limits and what a normally functioning engine would really do). However it's really hard to anticipate every possible scenario - and it appears that perhaps the pilots on this flight managed to come up with an unanticipated scenario for the Trent engine.