ADS-B "Blacklist"
Karl,
As you would expect, Airservices monitors ADS-B performance and carries out various checks before it uses ADS-B for air traffic control. With respect to the aircraft on your "Blacklist", they fall into several groups
7C6C6F //V Australia Boeing 777-3GZER VH-VPD
7C6C71 //V Australia Boeing 777-3GZER VH-VPF
C81C17 //Pacific Blue Airlines 737-8FE ZK-PBK
C817CC //Pacific Blue Airlines 737-8FE/W ZK-PBD
This group were all equipped with a version of a Mode S / ADS-B transponder that had a fault. This fault has now been fixed, so you can remove them from your blacklist.
E8023F //LAN Chile A-340-313X CC-CQF
E8023E //LAN Chile A-340-313X CC-CQE
These two aircraft are fitted with an old GPS transponder that does not meet CASA's requirements for an ADS-B data source. They should be upgraded before the flight level 290 and above ADS-b mandate comes into force in December 2012.
7C4366 //Nauru Air Corporation 737-33A VH-NLK
The standard ADS-B message from an aircraft includes information about the accuracy and integrity of the data source. This information is ignored by boxes like the SBS-1, but is critical for determining if the data is suitable for air traffic control. Transmissions from this aircraft indicate low accuracy / integrity, so it never gets through to the ATC system. The data source is probably an inertial nav system rather than GPS. Again, it needs to be upgraded before Dec 2013.
7C1473 //Qantas Airways A-330-202 VH-EBP
No problems have been observed with this aircraft. The only suggestion I can think of is that the observed anomaly might have been attributable to the position decoding method used. To unambigously determine an ADS-B position it is necessary to use "global CPR decoding", which requires processing of two separate ADS-B messages, referred to as "odd" and "even" message types. Some processing software uses "local decoding" with only one message, which sometimes produces anomalous results. Suggest you remove this one from your blacklist.
Regards
Bob.
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