NOT to make you all “There’s a man on the wing” paranoid, but there’s a lot that goes on aboard planes that we just don’t know about. In our travellers’ haze of in-flight movies, naps, and conversations with seat mates, we miss some intriguing (and sometimes unpleasant) parts of the flying experience.

But flight attendants and pilots see all and know all. And now, we take you behind the galleys and cockpits to reveal some of what really goes on lanes. How do flight attendants entertain themselves? How do they handle passengers they like and the ones they don’t? And is it really possible to join the Mile-High Club without them noticing? (Hint: No.)

Here are 12 surprising secrets about flying:

1. The real reason flight attendants rush you to take your seat

During boarding, flight attendants often sound like drill instructors on an obstacle course: “Let’s go! Stow your bags! Take your seats! Buckle up! MOVE IT, PEOPLE!!!” (But flight attendants are a lot nicer and more subtle about it.) Turns out there’s a reason for that urgency, and it’s not just about preserving the airline’s on-time departure rate.

“We don’t get paid until the doors close and the plane gets moving,” former flight attendant Shawn Kathleen, creator of Passenger Shaming said. She says many flight attendants are paid by the flight hour, and that clock doesn’t start running until the doors close and the flight is underway. “We’re just as motivated to get going as the passengers,” Shawn Kathleen says.

2. Flight crews don’t party during layovers (well, maybe a little)

Thankfully for us passengers, life on the road for pilots and flight attendants isn’t anything like the sex, drugs, and booze orgy we saw in the first five minutes of the Denzel Washington movie Flight. “On domestic flights, the layover is only ten or so hours,” says Tom Bunn, a former airline pilot and licensed counsellor who helps people get over their fear of flying. “Most crew members get a bite to eat, watch some TV and get a good nights sleep.”

“Of course, parties happen,” Shawn Kathleen says. But she notes that federal “bottle to throttle” rules barring flight crew members from drinking within eight hours of a flight (airline policies are sometimes even stricter) do a good job of keeping the vast majority of flight crews honest. “You can arrive for a flight and someone is there to give you a Breathalyzer or drug test,” Shawn Kathleen says. “Nobody f***s around with that.”

3. Empty flight shenanigans

Remember the lucky guy who had a flight to New York that was empty except for himself and another passenger? “Betty,” the anonymous flight attendant who writes the Yahoo Travel column Confessions of a Fed-Up Flight Attendant, says that happens quite a bit. “Every once in a blue moon we will ferry a flight,” she says, “which is when we deliver the plane, and ourselves, to a destination. So there are no passengers on-board, only crew members.”

And when the passengers are away, the flight attendants will play. One popular empty flight pastime is called “aisle surfing.” Betty describes it as such: “You grab a meal tray, put it on the floor in the aisle at the front of the plane, stand on it, hold on to something solid for dear life, and wait for the moment the plane lifts off from the runway. At that point — when the plane is travelling 140mph (225km/h)— you let go and slide clear to the back of the plane on the carpeting.” Betty says she’s never tried this dangerous activity because, “It almost always ends badly.”

They rebooked everyone but me on another flight to LGA, so I am literally the only person on this plane. pic.twitter.com/ZZNPACUOfR — Chris O'Leary (@ohhleary) January 12, 2015

4. Yes, the flight attendants are talking about you

“I will neither confirm nor deny whether crew members talk about passengers,” jokes flight attendant Emily Witkop. Fortunately, ex-flight attendant Shawn Kathleen is willing to dish on flight attendants’ dishing. “You might say, ‘That guy’s hot,’ and, ‘Oh, she’s hot,” Shawn Kathleen says.

Witkop (reluctantly) confirms that. “I recall for a few years there was a ‘hot coffee’ code among flight attendants,” she concedes. “You would say, ‘I’ve got hot coffee in 3B!’ Which meant there was an extremely attractive passenger in that particular seat who the other flight attendants should check out.”

5. The flight attendant can probably kick your ass

In addition to training in CPR, first-aid, fire safety, and even delivering babies, Shawn Kathleen says flight attendants are taught something else that might come in handy: self-defence.

“[The training] is probably like what a woman would learn at a normal self-defence class,” she says, noting that they practice with each other and with dummies. The self-defence training is mainly to deal with security threats, such as someone rushing the cockpit.

So your flight attendant likely won’t open up a can of you-know-what on the average difficult passenger who makes rude comments and keeps pushing the call button. Or will they? “We don’t want to, but … yeah, sometimes we want to,” Shawn Kathleen says, laughing.

6. If you’re being a jerk, flight attendants will mess with your drink

No, we’re not talking about … THAT. “I would never spit in [someone’s] cup,” Shawn Kathleen says emphatically. But that doesn’t mean she or her fellow flight attendants are above exacting some liquid revenge against a rude passenger.

Shawn Kathleen had one favourite, and harmless, tactic when serving up some payback to mean passengers: “I’ll take a cup and scoop in a lot of ice, and when I pour the soda or juice in, there’s, like, two tablespoons!” she laughs. Shawn Kathleen called her cocktail “The ‘A**hole Special,” and she’s certain other flight attendants do it, too. As they say: “Revenge is a dish best served cold.”

7. Don’t think your flight attendant doesn’t notice you trying to join the Mile-High Club

Amorous couples often think they’re being more subtle than they really are, and that’s definitely the case when they sneak off to the lavatory for some in-flight entertainment. Sorry, guys, but flight attendants can spot you a mile away. “We usually can shake our heads at people attempting to populate the lavatory together and give them the ‘No, no’ sign,” Witkop says.

But while flight attendants may notice your naughty intentions, that doesn’t mean they’ll always stop you.

“They’re adults,” says ex-flight attendant Shawn Kathleen, who admits that if there was a light crowd on-board, no one waiting for the bathroom, and no safety risk, she was more than willing to look the other way. That doesn’t mean she won’t judge aspiring Mile-High Club members.

“Why would anyone want to?” she wonders. “You know what those lavatories are like. They’re disgusting!” Speaking of which …

8. Lavatories really are disgusting (and don’t get us started on the tray tables)

“For some reason people fail to realise that the on-board lavatories are just glorified port-a-potties,” says flight attendant Sydney Pearl, creator of the website Diary of a Pissed Off Flight Attendant and author of a book of the same name. “We are always reminding people to put their shoes on because the wetness on the floor is not water!

“The tray tables are a close second to the lavatories. People sometimes change their kids’ diapers on the tray tables, and, yes, sometimes they are soiled! The worst part is that they just close it back up, and then I see someone on the next flight either allowing their kids to eat their snacks off of the tray table or someone asleep with their bare face on the table. Gross!!”

9. Flight attendants are stain removal experts

On crowded aeroplanes these days, spills are inevitable. Fortunately, flight attendants know how to deal with spills that threaten to stain your outfit. Says Emily Witkop: “One trick is not only to use the ever-handy club soda to lift the stain but to put in on a sanitary napkin (maxi-pad) to blot the stain.”

She notes that, unlike paper towels or napkins, maxi-pads don’t leave residue on your clothing. But Witkop admits some people are a bit unnerved by this … sanitary approach to cleaning. “You must use good judgment on who you offer this solution to,” she says. “They will either love it or be absolutely horrified.”

10. Games flight attendants play

Just because the flight’s over doesn’t mean the fun stops. ”Saying the requisite ‘buh-byes’ to 300 people can get very repetitive,” says Betty. “If there are two of us, we will pick a random way to separate the workload. For instance, ‘You take the passengers with the eyeglasses and I’ll say goodbye to the ones without.’ While it may seem silly, Betty says it’s a good way to stay engaged in each personal encounter so that “our smiles look genuine.” Plus, they get added laughs whenever they have to decide how to count a guy with an eye patch or a monocle.

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11. Cabin crew are beauty experts too

Flying is hell on the skin, but many flight attendants have a way to deal with the dryness that accompanies air travel. Says former pilot Tom Bunn: “Flight attendants have found that nothing keeps that moisture in better than baby oil.”

This article originally appeared on Yahoo Travel and was republished with permission via the New York Post.