How do the toilets on a plane work?

Your question of the month in March (2015)
Maya, 10 years old

Have you ever wondered how the toilets on a plane work? It is actually very simple. Our normal toilets, like the one you have at home, have a water flush system. Of course, that’s not possible on a plane – otherwise large amounts of water would need to be carried for so many passengers. On the one hand, this would take up a lot of space and on the other, the kerosene consumption would increase considerably due to the additional weight.

Therefore, so-called vacuum toilets are used on planes. With the aid of a vacuum, everything is sucked into the toilet, like a vacuum cleaner – if you have used a toilet on a plane before, you have certainly heard that loud noise they make. The toilets are coated with Teflon (the same as frying pans for example) to make sure as little as possible sticks to them. This is why only a little bit of water is needed to rinse the toilet.

The vacuum toilets are part of a "closed system" – this means that everything from the toilets is sucked into a sealed tank inside the plane, where it remains until the plane lands. Then, special vehicles arrive to empty the tanks and take their content to a sewage disposal plant. Very practical, don't you think?