Whether you're the type of person who loves the excitement of getting on a plane or you find it terrifying, there's one thing all air travellers can agree on - the toilets are pretty grim.
But, what else would you expect for a tiny cubicle 37,000 feet in the sky catering for hundreds of passengers?
Anyway, if you've ever wondered what actually happens when you go to the toilet on a plane, like where does it go and why on Earth is it so loud, then you're not alone.
Some people wrongly believe the waste is simply dropped out the bottom of the plane, but fortunately for those on the ground, that's not the case.
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For over 30 years, planes have used vacuum toilets so that they don't have to carry unnecessary water, which would drastically add to the weight.
According to Gizmodo : "Pressing the flush button opens a valve in the bottom of the bowl, exposing the contents to a pneumatic vacuum.
"That vac sucks the load down the plane's sewer line into a 200-gallon holding tank."
The toilets also have a sort of Teflon non-stick coating to assist in pulling the waste down. Waste remains in the tank for the duration of the flight and is vacuumed out by crews on the ground.
How do they ensure pilots don't accidentally drop the waste in mid-air? Apparently there's a latch on the exterior of the tank, so it can only be opened from the outside.
So, there you have it. Next time you're on a plane and pop to the loo, you know exactly what's happening. Just try not to think about the fact there's a 200-gallon tank of excrement under your feet.
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