Flying is an elusive business, and we rarely get to see what goes on behind the tightly closed curtain that leads to the cabin crew's quarters.
However, a revealing new series of threads on search engine Quora are giving us a glimpse into what what really goes on during a flight, with cabin crew lifting the lid on some previously unknown secrets.
You can read five of the most shocking below...
The blankets and pillows aren't fresh
You might want to think twice before you snuggle up under a blanket provided on a flight.
Ex-flight attendant Fatihah Sudewo revealed that a number of airlines simply fold used blankets up after a flight, ready to be offered to the next set of fliers.
"It depends on how cheap the airline is, but I've had my share seeing them [the cleaning team] refolding the blankets for the passengers on the next flight to use," she wrote. "At least they were generous enough to replace the pillow covers and the headrest covers."
If you can't stand the chill from the air con, be sure to ask for a clean blanket in a sealed plastic bag.
The food is up to 72 hours old
While it comes as no surprise to learn you won't be served a farm-fresh meal at 45,000 feet in the air, the food on flights can actually be up to 72 hours - or three days - old.
"You get served frozen food which is kept for up to 72 hours,' revealed a cabin crew member on the thread.
Your tray table is the dirtiest part of the airline
A cabin crew member revealed that the tray table, which we all use to hold our food and drink, is the dirtiest part of the plane.
Tray tables, described as "unhygienic", were confirmed as the grubbiest part of a plane last year by a biologist who tested all the surfaces of a cabin and found them to be the dirtiest, in a Travelmath report.
The headphones might not be clean
Unless you would be happy to share a pair of headphones with 10 strangers, it might be best to avoid the free pair handed out on most flights.
Fatihah Sudewo wrote, "Airlines who provide headphones like the one in the picture above hardly or even NEVER bother to replace the foamy-like ear parts."
Travel in the morning to avoid turbulence
Scientists have found that more storms occur in the afternoon, meaning there could be less chance of turbulence if you travel earlier in the day.
Writing on the thread, a frequent flyer called Anya said, "One of the things that flight attendants won’t tell you, is that morning flights are better because the air is less bumpy."