A33Zab : thank you for this
No doubt this is a wiring (WRG) problem, either internal in the PRIM2 or in the wiring from ADR1 ARINC BUS 1-2 from terminal to PRIM2
Now this is very interesting :
Could PRIM2 be in NORMAL LAW and others in ALTERNATE LAW, Very unlikely because ADR DISAGREE (due to PROBE PITOT 1+2,2+3,1+3) results in ALTERNATE LAW for all PRIMS.
Do you remember the timing for ADR DISAGREE in this accident sequence ? Time-stamp from CMC says 02:12 if I remember correctly. Can you tell us more about the difference between NAV ADR DISAGREE and F/CTL ADR DISAGREE ? Which system declares disagreement ?
Software or even program bugs? Very unlikely after all those years!
I never said it was likely or probable in general, quite the contrary. I said it was likely
in this instance.
How many successive software versions for the PRIMs ? Last time I checked, I thought I saw version number 19.
Again, this is a highly reliable and efficient aircraft. Its design philosophy has certain consequences, however. These consequences are not about safety, but about who can be deemed responsible for what.
Herr Professor Schmid wrote about this much better than I could :
Pilot or Computer in Command