Minesweeper
I've done a bit of cropping on this one, and also cloning to get rid of the worst of the purple felt-tip pen.
The legend on the back refers to one of the Queen's minesweepers leaving Plymouth, heading, presumably, for the Suez. There must have been some brouhaha in the Suez at that time. Can't remember, it was 21 years ago.
ScaryDuck commented
I think they were re-opening the canal after years of Arab-Israeli war. Or something.