buoy15
Your point <<… whether SCATC or SCATCMiil were holding secondary contact and/or VHF comms, immediately prior to the incident. irrespective of any settings or selections found on the D band transponder by the BOI.>>
is significant – one would have thought that this would have been made clear very early on in the inquiries and I believe that this is one area that interested parties should ask to be clarified.
From transcripts of the inquiries we know that ZD576 made a call to ATC but this call was either unanswered (some find this unusual, others say it can be expected) or possibly recordings after this point have not been made public. One would have thought that independent, expert analysis of the complete period of interest should be done – for example of the usefulness of this, at the very least the timing of even the momentary activation of a Tx button could have been revealing. It would be reassuring to have a statement from an independent expert that the VHF recording was complete over the period of interest (ie. no sign of editing).
Regarding secondary radar, there is one reliable source who claims (and reported in a newspaper at the time) that radar recordings showed the path of the aircraft right up to impact – unfortunately, to date he has not confirmed that this was from a secondary radar, nor what the observed squawk code was had this been the case. One would have thought that the squawk code set initially should have been stated (there was much talk of how it could have gotten to what it was from a general setting at the inquiries but the actual starting point was not stated) and, as I believe that it may have relevance, interested parties should formally ask what it was (under the Freedom of Information Act or whatever).