HN39, you're welcome...as I say, some meandering thoughts which may strike chords with others and take us forward.
Would that information coming from the ADIRU's in ADR DISAGREE mode be considered valid by the CPC's?
I'm keeping in mind that the ADRs themselves haven't failed but are receiving erroneous pitot data which the ADRs are rejecting, and the SDAC (or FWC) is creating the disagreement message. I'm not sure if ADR data transmission stops because of this, or downstream users are "told" that the data is bad, or that any further error detection and use of data downstream would be made independent of the ADRs with the equipment responding with error messages of its own.
Without further research, I would have to say that the ADR static pressure data would still be valid and providing the ADR pushbuttons remained ON, available for use downstream of the ADRs, but it's a question I can't answer. I'll keep looking.
mm43,
I'm thinking that in the fail safe situation that the pressure relief valves, once triggered could possibly be configured to also initiate the Cabin Vertical Speed Advisory. Any thoughts?
Just to be sure, the PRIMs don't send data to the CPCs. I'm not sure if recycling the PRIMs would have any effect but I doubt it.
Understand the thinking on the safety valves. As I see them at the moment, they appear to be mechanically driven, (
spring-loaded poppets) by differential pressure, (
positive, and negative - the negative pressure relief valve mentioned earlier is additional, due to the volume of the fuselage), with electronics monitoring position for the CMC. There is no description of, nor does there appear to be any other mechanism which would drive the valves open through other means, (in either direction).