ACARS Message regarding TCAS
First of all, my sincere respect for the knowledgeable discussion on here - extremely enlightening and informative, thank you very much!
After going through the posts, I have been musing about the ACARS message regarding TCAS (3443005) transmitted at 02:10. Can anything more specific than a TCAS fault be inferred from this code?
Generally, since it relies on ADIRU input for ownship pressure altitude (looped through the Mode S transponder according to the A320 AOM I have at hand, 1.34.80 P3, REV 23), I would expect TCAS to degrade, at minimum, to TA only level upon ADIRU failure.
Therefore - please correct me if I am mistaken - I think the TCAS error might be regarded as further indication for inconsistent/erroneous/unavailable air data sensor input - unless somebody can validate the claim by avherald.com that it relates to the TCAS antenna.
Regarding ADS-B, it is indeed intended, among others, for enhanced surveillance in non-radar airspace.
The implementation via 1090 MHz extended squitter (DF = 17) allows the transmission of, among others, Airborne Position Messages (~2 per second), Airborne Velocity Messages (~2/s) and Identification Messages (~1/5 s). This will give anyone interested in receiving the data the F-PLN callsign and flight state information within a range of, IIRC, ~ 200 nm.
Since the airframe was fairly new, I would expect from personal observation of more recently delivered Airbus aircraft that it was already equipped with ADS-B out. However, there was probably no-one within range to receive the data.
Chris