In reply to defaid:
Brilliant.
Travelling to and from the Shetlands around 1979, when I worked at Sullom Voe, I was on two charter flights where the pilot/s did a detour:-
1. At night the Northern Lights could be clearly seen from one side of the aircraft. This the pilot announced and to ensure both sides could see them he did a big figure 8 so everyone got a good view.
2. Flying over Scotland in winter I asked the stewardess if she'd tell me when we over the Cairngorms. Off she went to the cockpit. 20 minutes later I was invited into the cockpit where the pilot made some slight detours for me and I got a brilliant view of some of the hills I intended going over the next week...
3. Flying from an oil rig in the North Sea I was lucky enough to be invited by the pilot (who was also ex RN - like me)to sit in the dicky seat between him and the co-pilot. As we flew back to Teesside I could see a few miles off our course, two warships which I could tell were not RN and pointed these out to him. To my surprise the pilot decided to do a detour and we had a good fly around these two ships which were two Dutch warships.
I'm sure others have better tales to tell about air detours!!