o PROBE PITOT 1+2 / 2+3 / 1+3 (9DA) (2 h 10)
ATA: 341115
Source: EFCS2
Identifiers: EFCS1, AFS
Class 1, HARD
This message, transmitted by the FCDC2 (EFCS2), means that the FCPCs (or PRIMs)
triggered one of the speed monitoring processes: they have detected a decrease of more
than 30 kt in one second of the “polled” speed value. The three ADRs were considered valid
by the EFCS2 at the time the monitoring was triggered, because the prior rejection of an
ADR would have generated a class 2 fault message and there would therefore have been an
asterisk in front of the source. In this case, the “polled” value is the median value.
What I get from the text above is:
The BEA seems to admit that this fault might be generated by disagreement between ADRs although it states that such disagreement wasn't yet detected at the time the average of the speeds provided by the three pitots decreased 30kt in one second.
It is very interesting to notice that it is a class 1 fault report and therefore (I suppose) it was generated DIRECTLY by EFCS2 otherwise the term EFCS2 would be preceeded by an asterisc (*). So this fault would not come from the PHC
It might mean that only the speed component of (ADR1 ?) was contradicting the correspondent readings from ADRs 2 and 3 and that other ADR1 output, like altitude, AoA and so on was ok - Then making it possible to point to a probe specific problem - Or it might simply mean that the discrepancies among ADRs were sampled later.