Originally Posted by
henra
While I do agree from a technical perspective, historically in past accidents the ADS-B data rarely if ever painted a really different picture regarding trajectory/flight path and velocities than were later determined by the proper tools.
That has certainly been true - up to a point - for the dozens of accidents/incidents that have featured in these columns over the years and where FDR traces have subsequently been published in the investigation report (including the two Max accidents).
But there is an important caveat: ADS-B data (as transmitted by the aircraft) and an FR24 download (however granular)
are not the same thing. The latter will be subject to asynchronicity, hysteresis and latency - though many (but not all) of those issues can be mitigated with some work and patience.
So, while I have no sympathy for the knee-jerk "ADS-B is rubbish" view sometimes expressed in these columns, nor do I agree with the "ADS-B is gospel" view when applied to FR24 data.