Walter Kennedy
"With your experience I wonder if you would like to comment on the (apparently) incomplete radio dialogue between ZD576 and Scottish Military – why was there no answer to its (first and last) call?"
My colleague and next door neighbour was the duty controller. He did not hear the single call made by the aircraft. No reason could be determined, he just didn't hear it, it was only discovered when the radio tapes were replayed. The rules are that aircraft should make 3 transmissions before assuming that there is no RT contact.
"Radio hams have observed Scot Mil changing transmitters during dialogues"
Hhhhmmmm, Due to the large area of coverage Scot Mil transmitters and receivers are generally on two legs (two geographically distant places to give good coverage of the frequency). To give redundancy there is always an A and a back up B tx/rx and in the event of failure they're switched. The ATC controller has no method of selecting an individual leg nor of changing over the A and B tx/rx. It is conceivable that they could switch from A to B due to a failure but this would be transparent to the controller. Irrespective it is the frequency itself which is recorded.
"is it possible that there was a response recorded on a different channel that has been overlooked?"
No, all channels were examined.
"Regarding the article about the radar track: this was written very soon after the crash and would be unlikely to have been in support of any deep conjecture, more like just an immediate witness statement."
By whom? The only people who would have been able order a viewing of the replay immediately in the aftermath would have been the Distress and Diversion controller or the civil watch supervisor. Obviously whichever engineers set that up would have been able to watch as well. I videoed the replay for the BOI about a month afterwards (as far as I recall).
"The journo’s other work is extensive and in major publications over a long period.Whereas you wrote <<, what intense air activity would this be then? The odd Hawk going low level at Gigha Island?>> - having gone through transcripts of a/a and a/g comms during American/NATO exercises including helos at low level in that very area, I am very surprised at your comment"
Why are you surprised at my comment? I write as a highly experienced ATC who controlled in that area for 7.5 years and I am telling you that there was no requirement for a low level ATC service in the area of Mac. There were very few aircraft requesting descent to low level there.
I am curious about how you are able, through reading voice transcripts, to determine the position of the aircraft you write about? Yes there were many large scale JMC exercises at the time (about 3 a year) but they worked their way around Scotland, generally out of Rosyth and ending up in the Clyde.
On a final note about providing low level radar coverage in Scotland. There are vast tracts of Scotland which have no radar coverage, are you seriously suggesting that radar should be installed everywhere, on the off chance that there might just be an aircraft requiring ATC to give a low level descent once or twice a year?
"and, on the strength of this would believe the above mentioned journalist over this air traffic controller."
Oh I see, so I'm a liar. Well this ends my cooperation in trying to give you rational explanations from my professional experience to your delusional scribblings.
BD