Back in the ’80s and ’90s, it seemed like every stand-up comedian in the world had a bit where they asked, “What’s the deal with airline food?” Then, they went on a five-minute tirade about bland mystery-meat sandwiches and wilted lettuce. Of course, airline food isn’t really a thing anymore, so nobody wonders what the “deal” with it is. But there’s still plenty of other mysteries of flying we can ponder. Like why do we have to turn off our phones? And how do the toilets work? Those and other burning questions are all answered below as we tackle 20 questions you’ve always had about flying.

1. Why do you have to open window shades for takeoff and landing?

As much as the pilots and flight attendants want you to enjoy the spectacular sights of a landing in Sacramento, the reason you have to have your shades up is for safety. Should something go wrong, with shades up the crew can see fires, debris, or other hazards that may be outside. This way, flight attendants can better plan emergency exits and other procedures.

2. Why do I have to turn my phone off onboard?

Though it’s never been proven that cellular devices or signals interfere with an airplane’s electronic equipment, they might. This is why the FAA mandated phones be turned off, essentially to cover themselves in case it’s ever discovered that they actually cause interference. Though, honestly, is anyone really upset we can’t listen to other people’s phone calls on airplanes?

3. Why must electronic devices be turned off during takeoff and landing?

Much like with cell phones, computers and tablets don’t necessarily interfere with any part of a plane’s equipment, but the FAA errs on the side of caution in case they might. Also, in case of a rough landing or extreme turbulence, it also wants to make sure your tablet doesn’t become a giant flying blunt object.

4. Why do I have to put my seat and tray table up for takeoff and landing?

This is also done in case of an emergency. Though exiting an airplane is never an efficient experience, having seats and tray tables up when people need to exit quickly helps move things along.

5. What is that little hole in the window for?

Airplane windows are two-paned devices made of plexiglass. The outer window keeps air out of the plane, the inner one is there so passengers don’t accidentally break the outer window. The little hole in the inner window was devised as a pressure release, so that if the outer window does break, the air pressure won’t break the inner window too.

6. Why do planes fly at 36,000 feet?

The fact is 36,000 is just an average, as most planes fly somewhere between 30,000 to 40,000 feet. The ideal altitude varies by aircraft, direction of flights, and turbulence. It’s also where planes can catch the jetstream to help push the plane along.

7. Do you really get drunker when you’re flying?

Technically, no. Though anecdotally people say “booze hits you harder at altitude,” your actual BAC does not increase based on how high up you are. But because you have less oxygen going to your brain, and the air is bone dry, you may feel the effects a little more. And you’ll definitely get dehydrated faster — meaning those post-flight hangovers might be nastier.

8. What happens if an engine fails?

Ever seen a hang glider? No engines on those things, and they fly around just fine. Think of your plane as a giant hang glider, with engines used to generate enough thrust to get it in the air, then push it along a little faster once it’s there. If one engine fails, you might not even notice. If both fail, you’ll definitely notice, and will have to make an emergency landing somewhere. But the plane will glide until it can’t anymore, and will not fall out of the sky like there was an executive order repealing the laws of physics.

9. What happens if somebody dies on a plane?

Singapore Airlines once had an infamous corpse room for its long-haul flights, where dead bodies would go should someone keel over mid-flight. It doesn’t exist anymore, and now flight attendants will either move the deceased passenger into an empty area like a lavatory, galley, or empty seat. Lacking those, they will cover the body with a sheet until landing.

10. What happens if a plane gets struck by lightning?

There’s an urban legend that says an airplane is the safest place to be when you get hit by lightning. Though this hasn’t been proven statistically true, lightning strikes don’t affect the plane a whole lot. The average plane actually gets hit about twice a year, but no major commercial crash has been traced to a lightning strike.

11. How far do you fall during turbulence?

Though it might feel like you’re on an airborne version of Deadliest Catch during particularly rough turbulence, the fact is you aren’t falling far. Most chop that requires holding onto the lavatory handle is only a few feet. When the pilot asks the flight attendants to take their seats, you’re looking at a 10 to 20-foot drop. The absolute most you’ll ever drop is about 100 feet, which, while terrifying, is still less than your fall at half the roller coasters at Cedar Point.

12. How do the toilets work?

The toilets are like a way-grosser version of those vacuum tube banks used to send you money at the drive through. Unlike home toilets, that drain water out of the bowl and into the sewer, plane toilets are vacuum tubes with openings into the bowl. Flushing sucks whatever’s in the bowl into the tube, which leads to a tank in the tail of the plane. It’s kept there until landing, when the tank is refreshed.

13. Do toilets really drop frozen waste on people?

New planes do not do this, and most tales you see on the news of frozen airplane waste denting a car or ruining a quincenera are actually bird droppings. That said, some old models do still drop waste down over areas they assume are unpopulated. But it’s extremely rare.

14. Where is the safest place to be during a crash?

Those big seats and free drinks up in first class are nice and all, but if you’re into stuff like crash safety, the back of the plane is where it’s at. A 2007 study from Popular Mechanics looked at 36 years of NTSB crash data and found in the extremely rare event of plane crashes, you’re statistically safest near the tail.

15. Why do planes still have ashtrays?

Anyone who’s listened to 10 seconds of a safety demonstration knows smoking is illegal on planes. But for some reason you’ll still see ashtrays on lavatory doors, and occasionally armrests. The reason is in case some rogue passenger just INSISTS on lighting up during a flight, they’ll have somewhere to extinguish said cigarette so there won’t be danger of a fire onboard.

16. Are flight attendants ever scared of crashing?

You’d think someone who flew multiple times a day, multiple times a week might be afraid the law of averages would catch up with them. Not so much. According to a recent survey of flight attendants from Stratos Jets, fire onboard is actually their biggest concern, with 96 percent fearing it. Only 79 percent were afraid of crashes.

17. Why does my skin dry out on planes?

Air on planes is pressurized at about 10,000 feet, meaning you’re getting similar air as you might atop a small mountain in the Rockies. It’s also painfully dry, kept at a throat-scratching 20 percent humidity, or about the same moisture you’d find in the Sahara.

18. How fast are you going at takeoff and landing?

You ever notice how sometimes you put your laptop on the floor only to find it slide about 10 rows up because you’re going so fast when you land? That’s because takeoff and landing speeds are generally in the neighborhood of 150 to 200 miles per hour.

19. Why are the lights dimmed for takeoff and landing?

This isn’t done to create a romantic mood as you stare at the bright lights of Grapevine, Texas, on your ascent to the heavens. It’s done so that, in case there’s an emergency, your eyes are already adjusted to dim lighting, and you won’t be running around half-blinded trying to evacuate the airplane.

20. Why do I cry at movies on planes?

Okay, maybe YOU don’t, but the phenomenon of overly-emotional reactions to inflight movies is a real thing. So much so Virgin America began putting “emotional health warnings” before some particularly tear-jerking films. No concrete study has been done but psychologists chalk it up to a combination of the stress of flying, the extreme isolation of staring at a screen with headphones on, and decreased oxygen to the brain. Or maybe we’re all just getting soft.