What happens when you flush?

What happens when you flush?
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If you’ve ever flown on a plane, you may have thought about what happens to waste after someone uses the restroom. After all, there isn’t any plumbing up at 9000 metres. Keep reading to find out what actually happens once you flush.

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How did early aeroplane toilets function?

How did early aeroplane toilets function?
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If you’ve ever imagined the contents of your aeroplane toilet dropping out of the bottom of the plane like a surprise crop-dusting, you’re not the only one. It’s not so far-fetched – this actually used to happen. The very earliest aeroplane toilets were primitive and direct: think bucket or bottle.

Airlines introduced a toilet that used Anotec – blue deodorising gel that flushed away waste and combated odour. It wasn’t without its problems though; airlines had to store litres of the stuff, which was very heavy and resulted in planes wasting precious fuel and having to limit passenger space. In addition, the storage tanks were directly below the toilets, so the smell would sometimes drift up into the cabin – not something you’d want to experience before tucking into your in-flight meal!

And those early toilets weren’t foolproof. Toilet waste sometimes leaked to the outside of the aircraft, where it froze. As the plane descended, it would drop icy lumps of blue gel mixed with faeces, which sometimes plummeted to earth at great speed, reportedly damaging cars and houses below.

Do planes dump waste into the air?

Do planes dump waste into the air?
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Not anymore! Back in the days of the bucket or bottle, passengers simply hurled the contents out the aeroplane window onto the unsuspecting world below. Given how glamorous early flying looks in vintage photos, it may seem kind of déclassé that the toilet systems would be so subpar. But once commercial flying became popular and pressurised cabins were introduced, bathroom systems saw an upgrade as well.

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Where do aeroplanes dump their waste?

Where do aeroplanes dump their waste?
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In 1975, James Kemper designed the modern aeroplane toilet, which featured a nonstick bowl, a small amount of Skychem (disinfecting liquid), and powerful vacuum suction. Now when you flush an aeroplane toilet, a trapdoor in the base opens, liquid is released, and everything is sucked out faster than a Formula 1 race car. Waste whizzes through the plumbing to the rear of the plane, where it’s stored in sealed tanks, well away from passengers, until the plane touches down. On a long-haul 747 flight, travellers might flush the toilets around 1000 times, creating roughly 1000 litres of sewage – that’s a lot of waste! When the aircraft lands, a ‘honey truck’ siphons out the waste and disposes of it into the airport’s underground sewage system.

In case you’re wondering whether planes might accidentally empty the tanks in flight, delivering a nasty shock to anyone below, not to worry. The door has external clips to prevent such unexpected accidents from occurring. And if you’ve heard the urban myth about toilet vacuums sucking out your insides, that’s not likely either—at least there are no recorded incidents to date.

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Source: RD.com

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