We’ve all done it.

We’ve all stared at that half-full can of soda that’s just been poured into our cup, wondering what the Flight attendant plans on doing with the rest of it.

But here’s the thing — you can have the whole can, you just have to ask, they’ll give it to you.

This and other pearls of wisdom are being shared by pilots, flight attendants and cabin cleaning crew on the social-news website, much to the delight of travelers who don’t often have such a frank exchange with the people who know the skies the best.

Even if you already know about airlines’ “give ‘em the whole can” policy, chances are there are Passenger nuggets in the Reddit Story you don’t know about.

Bathrooms
Airplane bathrooms can be unlocked and opened from the outside. All of them.

Every pilot and flight attendant knows how, and probably a number of the passengers do, as well. So be careful what you’re trying to pull in there.

Cabin lights
When taking off and landing at night, lights are turned off in the cabin to allow your eyes to adjust to the darkness. In the event of an evacuation, you’ll be able to see better.

Blankets, pillows, magazines
The pros say don’t use the blankets and pillows if they aren’t wrapped in sanitary plastic, unless you enjoy sharing unknown pieces of humanity with random strangers. Also, the magazines are probably the dirtiest things on an airplane …

Opening doors mid-flight
Ever stood next to the emergency door and worried about some maniac yanking it open at 30,000 feet?

Relax. Individuals simply don’t have the strength to open a door in-flight.

Try it and you may freak out your fellow passengers, but at high altitude that door simply won’t budge. (CNN travel guru Richard Quest says it’s not just a case of strength and air pressure, but one of design. He says the design aircraft manufacturers use these days makes it impossible for a passenger to open a door while in-flight.)

Flight deck visits
Think Flight Deck Visits are verboten after 9/11? Not so.

“It’s OK … when the plane is on the ground, it’s the best part of my job, especially when the passenger is interested and has lots of questions,” says one pilot on the Reddit story. “You can ask during boarding to take a peek in depending on how busy we are, but it’s better after landing when everyone is disembarking.”

What they won’t tell you during emergencies
“If we’re not going to make it, we’re definitely not going to tell you,” says one flight attendant on the Reddit story. “The last thing we need before we die is a riot.”

On the subject of emergencies, CNN’s Richard Quest has a tip of his own: keep your socks on and your shoes handy.

“Do not remove your shoes during take-off or landing,” says Quest. “If something were to happen during take-off or landing and you’d need to evacuate the plane, you wouldn’t want to be running on the runway over debris and burning fuel in your socks, now would you?”