Most air travellers want to sit by the window and enjoy the flight by observing different sceneries under the plane. If you happen to sit close to the wings, you might have noticed a couple of loops there. People have speculated what are they for, but the answer is much simpler than you’d imagine.
The wings of today’s airplanes are very slick. Engineers of companies such as Airbus and Boeing do their best to minimize drag in order to improve efficiency. So that little weird loop you see on the wing of an Airbus A320 is a little bit odd.
Some people thought that it might actually have something to do with aerodynamics. Others say that they attach special covers for the wings through those loops. Some imagine that the plane might be suspended by those loops when it needs servicing or when it needs to undergo some tests. However, the real reason for the loops existence is much simpler than these people think.
Captain Joe, a Youtube channel dedicated to answering people’s questions about airplanes and flying, answered this question once and for all. These loops are a safety feature.
In case of an emergency landing, emergency exits over the wings are likely to be used. However, if they are wet (if a plane landed in water or it is raining outside), wings will be slippery. Therefore, these loops are used to attach escape ropes. One rope is attached between the mysterious loop and the emergency exit door, and another one connects another loop to the emergency slide. Passengers can use these ropes for support and then avoid sliding around, falling and injuring themselves.
Captain Joe also explained what are the the mysterious triangles over two of the windows on either side of the passenger cabin. People were thinking whether they mark the plane’s gravity centre (which coincidentally they almost do) or a spot for cutting the fuselage in case the rescue team needs to open the plane with more aggressive methods. However, these triangles just mark the front and trailing edges of each wing, which is helpful if, for some reason, one of the pilots needs to take a look at it.