My commiserations to all his family. I was fortunate to fly with Graham whilst tasked with repairing a Hunter at Lossiemouth, many moons ago. Graham was doing a survey on clouds I believe, flying in the Shackletons, and managed to get me a trip with him one day. A great bloke, and very knowledgeable, who was even more fun in the mess bar, post aviating. It's sad to hear of the passing of good men.
Smudge