Next time you’re in an airplane, scan the walls. You might spot four black or red triangle stickers above the windows, two on each side of the plane. They probably don’t mean anything to you, but they mean a lot to flight attendants.
If you go up to the seats with the triangles and look out the window, you’ll notice the stickers line up with the edge of the airplane wing—one for the front, and one for the back. These stickers are just one of the 7 hidden airplane features you never knew about.
When flight attendants or pilots need to look at the wings, the triangle stickers act like a sign telling them exactly where to look. If they’re checking the moving parts of a wing (the flats and slats) for problems like ice, they won’t have to crawl over ten passengers before finding the best view, according to Travel + Leisure. Find the answers to 11 more airplane questions you’ve always wondered.
Queasy passengers might find their own use for the wings, too. The wings are the center of gravity on most planes, and the aircraft moves up and down from the wings like an axis. Sort of like sitting in the middle of a seesaw, you’ll get the least movement and smoothest ride by sitting over the wings, according to pilot ‘Captain’ Joe.