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Old 13th Jun 2011, 20:21
  #1938 (permalink)  
A33Zab
 
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WRG

WRG

A33Zab : thank you for this


Quote:
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
Don't forget to mention connector, pins & s'u'ckets!

Now this is very interesting :


Quote:
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 ?
Flight Computer Data Concentrator 2 (FCDC2) aka EFCS2 is the detector for NAV ADR DISAGREE and declares ALT 2 LAW.
A F/CTL ADR DISAGREE msg doesn't exist, only NAV ADR DISAGREE.

From the report:

"The combined triggering of these monitoring processes has the following effects:

at the level of the EFCSs:
switch to alternate 2 control law,
unavailability of the rudder deflection limitation function which occurs, when applicable, ten seconds later."

Last edited by Jetdriver; 14th Jun 2011 at 03:37.
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