Airplane toilets suck … literally.
Airplane toilets are anything but an easy touch-and-flush operation. Flight experts wowed travelers after revealing the “extraordinary” amount of engineering that goes into allowing people to soundly do their business at 40,000 feet.
Generally, the airplane setting takes essentially the most mundane tasks — from heating water to, well, using the bathroom — to latest heights of difficulty attributable to safety concerns.
“Every little thing is twice as hard on a plane as on the bottom,” Al St. Germain, an aviation industry consultant who’s worked for airlines including Delta and United, told CNN.
Flushing airplane toilets with water is prohibited attributable to aircraft weight restrictions — not to say that the water would slosh out of the bowl upon hitting turbulence.
Fortunately, scientists devised a Plan B: Air. That’s right, waste matter is sucked out of the plane using a differential pressure (somewhat than the passive siphon system employed by most terrestrial toilets) in a system patented by James Kemper in 1975.
When the bathroom user presses the button, a valve opens up within the bowl connecting to a pressurized pipe. This then sucks out the bowl’s contents like a high-altitude Hoover vacuum — hence the contraption’s moniker “vacuum toilet” — after which the valve snaps shut.
“It’s like your vacuum cleaner – it sucks,” explained Nigel Jones, an aircraft engineer from Kingston University in London.
This suction effect is brought on by the natural difference in pressure between the cabin and the skin atmosphere that’s generated by the plane climbing into the sky (it doesn’t occur when the aircraft is on the bottom).
Actually, the vacuuming occurs repeatedly throughout the entire fight, but we only hear it when the valve opens.
Then, in fact, there’s the age-old query of where the contents go after getting flushed.
Contrary to popular belief, waste matter isn’t just shot out of the airlock into the sky a la “Goldfinger,” but somewhat goes into pressured waste tanks, that are generally positioned at each the rear and front of the aircraft.
These are then emptied into “honey wagons,” special waste disposal vehicles that transport the contents to the airport for processing.
While the mechanism could seem strange, vacuum toilets boast many benefits over their siphon-based counterparts, even for normal, non-plane-based installations.
These include narrower sewer pipes, the flexibility to flush in any direction as these loos don’t depend on gravity, and in fact, the incontrovertible fact that they flush with minimal water, which makes them eco-friendly as well, in response to HowStuffWorks.com
On average, vacuum potties use half a gallon or less, in comparison with 1.6 gallons for a water-saving toilet and as much as 5 gallons (19 liters) for an older toilet.
Better of all, the bowl is entirely coated with Teflon so the whole lot slides right off, precluding users from having to make use of a bathroom brush.
In fact, these sky thrones aren’t without their downsides.
For one, airplane toilets do are inclined to get clogged steadily, especially when passengers throw diapers and other unauthorized items down them. This generally is a nightmare to rectify given the labyrinthine pipe work.
Actually, only one or two blocked johns is enough for pilots to ground a flight attributable to the limited variety of facilities
There’s also the problem of airplane sewage getting by accident expelled into the atmosphere due to a leaky discharge pipe.
As the skin temperature is usually below freezing, any liquid will “popsicle” (poopsicle?) upon contact with the air, forming what’s often called “blue ice” within the airline industry.
“It will get to a degree where it’s too heavy to stick to the bathroom servicing panel, so it will fall out and that’s what blue ice was,” explained Jones.
In 2021, an unlucky fellow who lived near London’s Heathrow Airport was unceremoniously splattered with poop for this reason very phenomenon.
To make matters worse, the excrement didn’t get a probability to freeze beforehand attributable to the plane’s proximity to the bottom.