Brendan - Sorry I don't know much about what happened to Dennis Cooper. I left Southampton in 1972 and I believe he took over from me as SATCO for a short while but then left (retired?) not long afterwards. My abiding memory of him was one day at Southampton when an RAF Devon arrived carrying an officer of Air rank who was met with a guard of honour before being driven off in a staff car. Dennis, observing this from the tower, looked down and said, "Ah, it's old Tommy! Of course, he never got anywhere!"