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Old 15th Dec 2015, 11:32
  #19 (permalink)  
DaveReidUK
 
Join Date: Jan 2008
Location: Reading, UK
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Originally Posted by Dont Hang Up
If the aircraft was falsely reporting a high integrity ADS-B then this would be a significant safety issue.
It's not an "if" - the aircraft in question were falsely reporting a high integrity ADS-B and this was categorised (by Airservices Australia) as a Class C operational risk (though I can't find a definition of that anywhere).

Similarly, the Canadian take on the issue:

"Nav Canada’s permission to provide reduced separation using ADS-B is based on the premise that ADS-B position reports contain integrity values (NIC, NAC, NUC, SIL) that provide assurances for their use by ATC. The position anomalies generated by the B787 ISS are the first of their kind, and appeared to be a critical failure in the system; the provision of data with false integrity.

Nav Canada reviewed the nature of this error source against the assessment process which permitted ADS-B to be used as a surveillance source. This particular scenario of an aircraft continuing to report position with the required integrity values when it is in fact not in that position, was never imagined, nor covered, during any of Nav Canada’s hazard identification and risk analysis work."
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