Originally Posted by
takata
Now, Greek DOD was allegedly wrong about radar tracking showing that the aircraft departed from altitude at FL370... say "head of Egyptair navigation services".
EgyptAir plane 'did not swerve' before crash - AJE News
Everything "leaked" so far is looking as reliable as usual...
I have been curious about the Greek turn and circle and dive info. Primary radar shows distance to an echo and a trace (and Doppler shift) shows path, primary radar does not appear to show height information for example. This is provided by the Mode-S transponder which is the key to seeing when the Mode-S transponder failed to respond. I would have imagined it to be at the same time as the Mode-S blip and data disappeared from Radar screens which was 00:29 (according to the Egyptians) and coincident with the failure of ADS-B data feed and no subsequent ACARS data.
I am not sure of the distance to the Greek Radar station and whether it can actually receive an echo for the primary radar target at the same distance and height as the aircraft. One reference suggests that a range of 220 nautical miles at 40,000 feet for (primary ?) radar to see past the curvature of the earth. I am sure that there are a host of other more sophisticated systems but I find it difficult to believe that Greek radar so far away could detect a turn and descent and a circling and further descent to 10,000 feet using Primary Radar and even using Secondary Radar if the aircraft transponder was still responding.
It is further strange that Egyptian Radar, which should have been closer, was unable to detect the same data as the Greeks.