Since the advent of flight, joining the "Mile High Club" has had a certain sordid appeal to travellers.
Even back in 1785, two years after the invention of the hot air balloon, two English lords made a wager over whether one could have sex "in a balloon one thousand yards from the Earth".
Lord Cholmondeley succeeded in his endeavor – and his two guinea bet against Lord Derby resulted in a gain of 500 guineas and the lofty title of the first member of the Mile High Club.
This tale was recently recounted in an article for Vice, which also collected a number of stories from travellers on how they gained their membership – including one clever trick from a man who said he'd done it twice.
David, a 29-year-old member of the Mile High Club since 2012, said the key to pulling off some bathroom fun was to feign illness.
"You wait until the air hostess is busy with the drinks trolley, and then you pretend to feel sick in the stomach," he told Vice.
"You rush to the bathroom, and a few minutes later your 'friend' comes in to give you some water. Then you have roughly 10 minutes to reach your desired destination.
"I've done it twice now. Both were successful. You come out of the bathroom looking dishevelled and a bit sweaty, which is completely understandable… as you are not feeling well."
However, joining the Mile High Club is not all fun and games – it can have seriously consquences.
One traveller found out the hard way, when she was banned from Virgin Atlantic after being caught in a 747's bathroom with another passenger.
Singapore Airlines even banned the practise, after unveiling the first-class double-bed "suites" on its plush, double-decker Airbus A380.
The airline publicly asked passengers to stop having sex in them, as the suites were not soundproof or completely sealed.
"All we ask of customers, wherever they are on our aircraft, is to observe standards that don't cause offence to other customers and crew," the airline told Reuters in a statement.