FCC needs the ADR data for computation of stearing commands while the FMGC needs it to compute navigational data.
My guess is that F/CTL ADR DISAGREE is showing when the FCCs have problems with ADR data, while NAV ADR DISAGREE comes on when the FMGC has problems with it.
I looked at 1 QRH from 1 airline, and 1 FCOM3 from a different airline... one has F/CTL ADR DISAGREE, the other has NAV ADR DISAGREE.
NAV ADR DISAGREE
This caution is triggered by the PRIMs, when they only use 2 ADRs, and these 2 ADRs disagree. This may occur when:
- One ADR has already been selected OFF by the pilot, or
- One ADR has been eliminated by the PRIM, without any caution, because it deviated from the others.
F/CTL ADR DISAGREE unfortunately has no descripton.
The procedures are identical (both versions are roughly from the same period)..
AIR SPD... XCHECK
- IF NO SPD DISAGREE
AOA Discrepancy
- IF SPD DISAGREE
ADR CHECK PROC...APPLY
F/CTL ALTN LAW (PROT LOST)
Note: Following an ADR disagree detected by the PRIMs, the ALTN LAW is latched. Resetting the PRIMs using the pushbutton will not allow recovery of normal law.
- MAX SPEED... 330/.82
STATUS
- MAX SPEED... 330/.82
CAT 3 SINGLE ONLY
RISK OF UNDUE STALL WARNING
RUD WITH CARE ABV 160 KT
INOP SYS
RUD TRV LIM
CAT 3 DUAL
Where one has NAV ADR DISAGREE, it doesn't have F/CTL ADR DISAGREE and vv.
Both are caused by the PRIMs rejecting 1 ADR and the other 2 disagree with each other... but are they identical? I guess this depends on the airline on where it wants the ADR DISAGREE to appear... coz, I looked at an Airbus document, and it just says "ADR DISAGREE"... *shaking head even more in confusion*. Perhaps it depends on the FWC standard one is using.
is the 34-11-15 fault to be taken as all 3 probes failed together, or as n°1 heating failed ? Finally, how many probes are deemed failed as we can deduce from this message ?
To be honest, I am not sure it means 3 of them failing together...
EFCS1, AFS - PROBE PITOT 1+2/2+3/1+3 (9DA)... AFS senses fluctuation or rejects an ADR, asks EFCS1 to compare the rest, 9DA as problem's suspect. I have a separate list showing 34-11-00, failures of inputs... most of the list is sensor power supply and switching... 34-11-15 is something else... (and different airlines may have different numbers).
ADIRU1 BUS ADR1-2 TO FCPC2 yes ADIRU1 BUS ADR1+2 TO FCPC2 makes more sense...
The thing is, I don't know the databus layout... ADR 1+2 Failure I think would occur if PRIM1 or none of the PRIMs receive the data... unless PRIM2 was the Master Prim at the time...
The "-" instead of the "+" could have just been a typo...
The devil hides in the details :
INDEED !!!!!
we need to seriously evaluate the difference between NAV ADR DISAGREE and F/CTL ADR DISAGREE.
Svarin, read the above... and I need new glasses now because of the same thing! Still no satisfactory answer though...
How did you get to the relationship between air & phc data and the IR2 fault reported by disagreement with IR1 and IR3 ?
I'm just reading what I got...
I think Inertial Data is independent from air data - and that the opposite is not true - so an IR fault would only be detected by comparison with inertial data...
That's what we all believe in... but somehow there's a relationship somewhere... be it just a crosscheck/diagnose function, or a relational function... The thing that caught me was that the FPV would disappear... FPV would largely be a result of all things IR and the only ADR part is barometric... but that's a downstream relationship... the other thing that caught my eye is the report from the VH-QPH upset (26Sep2006) and VH-QPG ADR/IR fault (27Dec08), where it too found a relationship between ADR and IR when one of them of the same ADIRU was faulty and/or switched off (unless my eyes deceive me)... But the wording from the manuals seems to say that they both perform their computations independently from another... But if they need data relationship, surely the loss of one function over the other should just mean degradation and not failure...
Still got a lot of reading to do (and repeat readings)...
PK-KAR