This tiny hole in the window of an airplane window is of vital importance.
In an airplane window, nothing is left to chance. Neither its shape nor its manufacture. Airplane windows are made up of three layers, each with a specific function. Its shape also was not studied randomly. Although this may seem like an aesthetic choice, this oval shape is above all dictated by security constraints. However, in the early days of aviation, windows were… square! But after several accidents – often tragic in planes – the manufacturers opted for an oval shape.
In the mid-20th century, amid the development of aviation, airplanes began flying at higher altitudes, which allowed them to avoid turbulence and other adverse weather conditions. This was also intended to reduce air resistance and, therefore, fuel consumption. High-altitude flights have thus become more common, leading to crucial changes in the design of the aircraft themselves.
It is this increase in altitude that led designers to turn to oval portholes, so much so that rounded windows are now on almost all planes. This oval shape is, to summarize, more suitable for uniformly distributing the tension generated by the pressure difference in aircraft. It must obviously be accompanied by particularly resistant materials.
Contrary to popular belief, airplane windows are not made of glass, but of acrylic, a stronger and more durable material. Each plane window is made up of three layers: an inner layer, closest to the passenger, which serves as protection to avoid contact with the other layers under pressure; an outer layer which is part of the structure of the aircraft and supports the pressure at these altitudes and finally an intermediate layer as reinforcement to maintain the pressure in the event of damage to the outer window.
But another tiny detail might have already caught your attention on board an airplane: this tiny hole, located at the bottom of the window. This small hole inside the plane’s windows, the size of which does not exceed a few millimeters, plays an essential role in avoiding pressure problems in the plane: it acts like a valve and regulates the pressure between the interior and exterior window.
As you can see, in the world of aviation, nothing is left to chance, even the smallest details! And that’s good, aviation accidents are inevitably the most fatal…
