Airplane toilets suck … literally.
Airplane toilets are anything but a 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.
Typically, the airplane setting takes probably the most mundane tasks — from heating water to, well, using the bathroom — to recent heights of difficulty because of safety concerns.
“All the things 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 because of 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 (reasonably 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 in 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 attributable to 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).
The truth is, 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 reasonably 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 appear 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 undeniable fact that they flush with minimal water, which makes them eco-friendly as well, based on 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 toilet brush.
After all, 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 might be a nightmare to rectify given the labyrinthine pipe work.
The truth is, only one or two blocked johns is enough for pilots to ground a flight because of 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 mostly below freezing, any liquid will “popsicle” (poopsicle?) upon contact with the air, forming what’s often known as “blue ice” in the airline industry.
“It could get to a point 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 likelihood to freeze beforehand because of the plane’s proximity to the bottom.