Originally Posted by
groundbum
I was worried when I heard since MCAS was fingered that a cross FCC bus was added to handle it better. That's major tinkering with major components.
Pretty sure cross FCC bus is already there, not absolutely sure AOA is on it, but if not, adding it would be a lot different to creating entirely new bus.
MCAS could have been done with two AOA sources in the first place, it wasn't (allegedly - see whistleblower quotes further up thread) because that would require an MCAS-fail warning light and sim-training. This now appears to be being done in a half-arsed way by using AOA-disagree as a de-facto MCAS-fail warning, which means operators who don't currently have AOA-disagree option will presumably need to implement extra training (or get blamed for future MCAS prangs) but the US operators with the no-sim-training penalty clauses will not because they already have the AOA disagree option. Funny that...