Can't find much online but the BBC says it took place in 1987 on a flight from Reykjavik to Glasgow and that 4 were killed on board when it crashed 8 miles short of the runway. That would be around the area of Howwood where I remember the crash taking place.
I thought there were only 1 or 2 on board from memory, but could be wrong.
Maybe one of the local aviation enthusiast groups could help out ??