On one occasion, while serving as prime minister during the Second World War, ( Churchill) was to take his first high-altitude airplane flight in an unpressurized cabin.
According to his biographer , when (he) went to the airfield on the evening before a flight to be fitted for a flight suit and an oxygen mask, he conferred with the flight expert who was to accompany him on the journey and requested that a special oxygen mask be devised so that he could smoke his cigars while airborne. The request was granted, and the next day Churchill was happily puffing away at 15,000 feet through a special hole in his oxygen mask.