What happens when you flush an airplane's toilet?
There are many things we never may understand simply because we never bother to think about them or take the trouble to find out. In the spirit of demystifying the secrets of the universe, let’s look at the enigma that is the airplane’s bathroom.
The first flight made by the Wright brothers lasted just 12 seconds, hardly long enough from the bladder perspective! However, when planes began flying longer durations, the demand for relieving oneself in an aircraft far above the ground, must have arisen. There appears to be no record as to who was the pioneer in peeing while in the air!
However, some records exist of how this “built-up-pressure” was taken care off during the Second World War. The Lancaster bombers for example, carried onboard “slop bucket” called “Elsans” named after the British company that manufactured them. These Elsans often overflowed in turbulent conditions with the contents being shared over the floor, walls and ceiling. They were also tricky to use, and during long trips, they tended to overflow. The dislike for this creation was so much that airmen preferred to relieve themselves in containers and then simply hurl their business out of the window. Some of these Elsans toilets may have been jettisoned behind enemy lines and these “bombs” could be an early example of biological warfare!
The modern vacuum toilets used in today’s aircraft weren’t patented until the seventies with the first one being installed by Boeing in 1982. The inventor was James Kemper. His nifty device uses a little blue liquid ---known as “Skykem” --- which is non-sticking, and a vacuum suction which washes away the stuff. As such, when one pushes the button, a valve opens at the bottom of the toilet bowl, exposing the toilet to a pneumatic vacuum. The vacuum swirls the contents, depositing all the collected contents into a “closed waste system.” Airplane toilets today rely on actively powered evacuations systems. Ever since Kemper’s invention, there has not been any major advance on aircraft toilet technology.
What happens to all that waste from the toilets of an airplane? Is it jettisoned into the sky? Contrary to popular belief, a pilot does not have the ability to detach the toilet tank and send it plummeting mid-flight. At the end of each flight, the toilet’s contents are vacuumed on to another tank at the back of a truck which gets emptied out when full, at possibly some designated locations.