JB
Hi, I will dig out the detail but quickly now I would like to correct you on one point - you wrote:
<< ... track analysis 035(M) had been the course all the way from Northern Ireland, so it is not surprising that it was set on the HSI.>>
Actually the track from Aldergrove to the position of waypoint change was 027M.
The turn to the right has been refered to often (eg Boeing/Mitchel analysis) - it was not a continuation.
If anyone interested does the detailed chartwork, they would find that the line from the position of waypoint change to the position of initial impact was near as damn it 035M which just happened to be the course set on the handling pilot's HSI - and 8deg change is not insignificant.