After talking to a Glider Instructor, he confirmed my fears in that it would have been rare to have had updraughts and downdraughts produced by hills of a height around 2000 ft that would have an effect on a plane a further 6000 ft above them... but not totally impossible - just very unlikely. It would depend on the shape and steepness of the windward face and the strength of the wind and to be realistic, using Google Earth in 3D mode, these hills in this area just don’t seem to be steep enough... but then again, maybe if the incoming air was hot enough, then maybe with a little help from this heat, it might just assist any updraught to go much higher than expected? I don’t know.... but on thinking this over, I came to another conclusion. Have a look at this Google Earth image:
It's rather hard to portray what I'm trying to show here, but it is quite possible that the wind was funneling up this valley and accelerating in speed until it hit the steep incline at the end, which would help it have a jet blast effect and possibly reach the higher levels needed. Here's a Google Earth generated profile that I have extended to show more altitude to give an idea of the scales of what we are looking at, and a possible wind flow – excluding the rotors that would occur at the lower levels as this particular photo editing program doesn't have any method that allows rotors to be drawn in....
The small green object is the approximate position MDX would have been in according to the calculations.
By the time Mike first made the call of seeing the lights of towns out on the coast, and by the time Sector One commented to Williamtown that it looked like MDX had made a turn to the east was in the region of 25 seconds which means S1 had seen 2- 3 paints indicating the turn. S1 commented it looked like about a heading of 120°M. But at 09:34:50 – about 20 seconds later he commented to WLM:
S1 – WLM: ..... heading right toward you now
At 09:36:10 S1 defined the radar position more accurately and said he was in the vicinity of 46 away from WLM on a bearing of 320°M to WLM. To understand this better we need to 'see' what the S1 Radar operator was seeing.
Admittedly, the radar screen was a lot bigger than this image, but you can still see getting an accurate position and heading is only really a generalisation.
As this image is of the radar screen in Sydney, the circular rings representing n.miles are from Sydney – not Williamtown, so to get a reasonably accurate distance using this screen of n.miles away from WLM would mean using a scale ruler and a bit of estimation... hence the extra time spent trying to work it out more accurately. Just the words, “46 miles according to me”, suggests that he wasn't sure. Remember he said earlier “Not very accurate these things”. S1 was obviously hoping that WLM could get MDX on his radar as then they would have a more accurate fix on it as well as knowing MDX was about to go out of range of their coverage.
Note the compass headings around the circumference. When S1 said it looked like he had turned onto a heading of about 120 meant that the paints had turned towards the 120 shown on this outer ring and as there was obviously no recording to fall back on of what was happening on the radar those days, the Sydney radar operator has just filled in a generalisation of what he can remember of that day. Note he has just drawn basically a straight line between the first identified point to the last, and yet going by the transcripts, this line was anywhere but straight.... hence only a generalisation! Due to the scale on the radar, I think the Radar operators were only guessing a lot of the time. Glenn Strkalj of the BWRS, (and also an airline pilot that used to fly a C210 in past years) wrote an excellent article as a result of an in depth study on radar in relation to MDX, and it can be downloaded from this link: https://www.dropbox.com/sh/sc6outtry1spawh/AAAtqup90aiSKYOpVtHP-MqTa?dl=0
and he also did an excellent Presentation in December 2014 found on this youtube link:
MDX pg 19