An Air China co-pilot puffing on his vape is being investigated after the 'smoke' from it entered the cabin and forced the plane into an emergency descent.
Now, veryone knows the rules that you have to obey to get on a plane - one bag only, don't be too pissed, have all of your stuff in one of those flimsy plastic bags, that sort of stuff.
Rule number one, though, once you're on the plane, has to be 'No Smoking'.
As we often hear immediately after that announcement: "This includes the use of electronic cigarettes."
You'd think that the people who'd be most responsible for knowing those rules would be the pilot, and their co-pilots. Apparently not if you're on an Air China flight.
On a flight from Hong Kong to Dalian, in Northwest China on Tuesday, an Air China Boeing 737 aeroplane was forced to plunge down to around 10,000ft after the co-pilot's vape caused the air conditioning to partially shut down.
This left the cabin with insufficient oxygen, and meant they had to make an emergency descent, reports Sky News.
They eventually went back up to their intended flight altitude and continued on to their destination, but it must have been terrifying for the passengers and crew on board who might not have known what the hell was going on.
China's Civil Aviation Administration said that smoke seeped through into the passenger cabin, in which there could have been up to 215 passengers, presumably terrified for their lives and thinking about sending final goodbyes to loved ones.
China News reported that Qiao Yibin, from the CAA's aviation safety office, said: "In the preliminary investigation, the co-pilot was found to be smoking an e-cigarette.
"Smoke diffused into the passenger cabin and relevant air conditioning components were wrongly shut off, without notifying the captain, which resulted in insufficient oxygen."
This is just over a month since a British Airways passenger was jailed for eight months after it was discovered that he drank three double vodka mixers in the hours before he was due to fly a plane.
Julian Monaghan claimed that he was well within the airline's 'bottle to throttle' limit of eight hours - can you believe that such a rule exists? - before trying to get on the plane from Gatwick.
Luckily, a technician smelt his breath and alerted the police.
The judge said: "You are in charge of a huge aircraft. The safety, if not the lives, indeed, of passengers and crew members are in the hands of the pilot.
"They are entitled to feel that they are safe."
Bloody hell. Let's hope this is not a regular thing.
Featured Image Credit: PA