If you have never flown, but are planning, perhaps this photo instruction will be useful to you.
Why did I decide to do it? Firstly, when I first got there, I probably spent a minute or more to understand everything. And if there is a queue outside the doors? Secondly, flying already 1-2 times a year, I saw that not everyone who used the toilet before me knows how to do it.
1. During the flight, if you want to stay healthy, you need to drink water (or other non-alcoholic drinks). It is also advisable to go to the toilet, even in order to stretch an oversized organism.
The toilets are very small, smaller than on trains, so I don't know how people who weigh 150 kg use them.
The toilet is open when the “fasten seat belts” display is off. A year ago we flew from Paris to Kiev, the turbulence was almost all the time, sometimes quite strong, and the toilets were closed for almost all three and a half hours, opened occasionally, so there was a queue.
Now in all four flights (Kiev-Paris-Valencia and Valencia-Amsterdam-Kiev) there was almost no turbulence, and if there was, it was such that the belts were not fastened.
In this photo you see a toilet, and above its lid, a folding table for changing babies. (By the way, airlines and airports do everything to make it comfortable to fly with them, the only problem is takeoff and landing, but our daughter, when she flew with a 5-month-old baby, found a way out). Bottom right - disposable toilet covers. Top right - napkins. Toilet paper under the washbasin.
See there is soapy water in the sink? - The previous passenger does not know what I will talk about next.
2. Above the tap on the left - liquid soap, on the right - paper towels. If you are flying from a foreign country to a foreign country, and there are no Ukrainian inscriptions, keep in mind that they are all standard, i.e., you are asked to dry your hands, drain the water from the sink (with a lever on the tap), and wiped the sink with a used napkin.
How to open the tap? Usually by clicking where the inscription Push. 
3. You can remember the word seatcovers, it comes in handy in other public toilets. 
4. After itself, of course, it is necessary to wash off. We don't throw anything but toilet paper down the toilet. We press the blue button, and do not try to press it a second time, if it did not immediately react, after 2-3 seconds. with a loud sound, it is flushed with a small amount of water and compressed air. 
5. Everything is clear here. Who does not understand Ukrainian, "paper towels" are "paper towels". 
6. Under the washbasin there is a container for rubbish, including used napkins.
On a long journey, it is important for a person to be able to satisfy natural needs. For this reason, you always need to know where these establishments are located: a food point, a resting place and a toilet. Below you will find out the answers to the following questions: is there a toilet on the plane, where it is, how it works and how to use it correctly.
Where is the toilet on the plane?
If you will be in flight for more than 2 hours, then this question is extremely important for you. Different aircraft have different number of cabins and their location:
- Boeing-737, A-230 and Tu-154 have three toilets: two are in the tail, one is at the entrance to the plane.
- The Boeing 767 has five toilets: two between economy and business class, one in the beginning, two in the middle of economy class.
- The Boeing 747 has eleven toilets: two at the end and at the beginning of the aircraft, three toilets on the second deck, and four in the middle of the cabin.
Depending on the airline, aircraft model and year of manufacture, the number of toilets and their location can vary significantly.
How is the toilet on the plane arranged?
Toilet on the plane
There is no need to worry that the waste is ejected from the plane the way it is on the train. On board the aircraft there are special tanks where the toilet flushes. For example, the Tu-154 has tanks for the front toilet with a volume of 115 liters and for the second one - for 280 liters, while the A-320 has only one tank for 170 liters.
Airplane toilet cleaning
Different airplanes have differences in how toilets work:
- In A-320, water for flushing comes from the aircraft water supply system. With the help of a vacuum, the waste is poured into a special tank.
- And in aircraft such as the Boeing-737 and Tu-154, the sewage system is closed and recirculated. Water is taken from a special tank, which is refueled immediately before the flight. When the waste is washed off, the filter does not release large particles, and the liquid that has been filtered is sent to a repeated circle. Chemicals are added to the tank to remove odors and disinfect the water. After the aircraft has landed, the waste is discharged and removed.
Toilet on the plane
As you can see, the principle of operation of the toilet on airplanes differs from the toilet bowls we are used to, which, for example, you can see in the online store buy-plumbing.rf.
What is the correct way to use the toilet on board an aircraft?
Toilet on the plane
There are some simple rules:
- The toilet is not allowed to be used during take-off / landing.
- For a good flush, before using the toilet, it is better to lay paper in it.
- Lower the lid first, then press the flush button.
- Throw out pads and diapers in the trash cans provided for this.
- The toilet door can be opened with the handle from the outside, located under the "LAVATORY" sign.
- Try to go to the bathroom 15 minutes after eating or 10 minutes before, as there is usually a long queue after eating.
- Do not use smoke-generating and dangerous products, do not smoke, as the smoke detection system may be activated, and you will receive a fine (in this case, you may be removed from the plane and taken into custody).
Knowing where the toilet is located and how the toilet on the plane is arranged, you will be able to feel comfortable during the flight.
And did you rule that sometimes something unpleasant can fly from heaven to earth?
An airplane, of course, is not a train, but ... even such cases are known to fly from it.
For example, in July 1998, a fisherman who was fishing near Straubing-Wallmühle airport, northeast of Munich, was doused with feces from an Airbus 320, the victim reported this to the police. In January 2000, a Spanish man narrowly escaped injury when a 4-kilogram ball of ice made of human excrement fell from a flying plane onto his car near Seville. The man was about to get into the car when suddenly an icy present, 20 cm in size, fell from the cloudless sky and crumpled the hood of the car. In November 2016, a piece of frozen excrement fell through a window into the house of a resident of the Dutch town of Amstelveen. And these are just three of a series of similar cases ...
How could this happen? Where did they all come from, because airplanes do not open airlocks to get rid of waste?
The first toilets on airplanes were simple buckets. There is no information about when the first flushing systems appeared, but so far there was no pressure in the cockpit to open doors and windows ... Now, of course, everything is not so.
Let's start with the main thing - where is the toilet on the plane
Different aircraft have different locations and number of cabins:
Tu-154, A-320 and Boeing-737 each have three toilets: one is at the entrance to the plane, and two are in the tail.
Boeing 767 - 5 toilets: 1 at the beginning of business class, two between business and economy class, two in the middle of economy class.
Boeing-747 - 11 toilets: two at the beginning and at the end of the aircraft cabin, four in the middle of the cabin, and 3 toilets on the second deck. 
How it works?
After the passenger presses the flush button in the toilet, a noise similar to the operation of a large vacuum cleaner appears. The reason for the noise is the opening of the valve in the toilet. It occurs due to the large difference in pressure in the toilet and in the space under it. Thanks to this vacuum, the entire contents, together with the smell, are sucked down.
At one time there was a tenacious myth that a fat person who will sit on the toilet during the flush can suck in this vacuum. So - it cannot!
When the plane is in the sky
Through special pipes, everything enters the tanks in the tail section of the aircraft. There are several such tanks on airplanes. For example, the Boeing 777, which can carry about 400 people, has three storage tanks for the contents of toilets. Each tank is connected only to its own group of toilets. Thanks to this, even if one compartment is full, toilets connected to other tanks will work.
The volume of these tanks varies from aircraft to aircraft. So, in the Tu-154 tanks are installed for the front toilet with a volume of 115 liters and for the second - 280 liters, and in the A-320 there is only one tank for 170 liters. Chemicals are added to the tank to disinfect the water and get rid of the odor. In order to save space in the tanks, the flush system is designed to use a minimum of water.
In A-320 toilet water is taken from the aircraft water supply system. In Tu-154 and Boeing-737, the sewerage system is closed and works according to the recirculation type — the toilet flush is taken from a separate tank, which is refueled before the flight. When the waste is washed off, large particles are trapped by the filter, and the filtered liquid is sent to a repeated circle to flush the toilet bowl. Chemicals are added to the tank to disinfect the water and get rid of the odor.
By the way, did you know that the weight of the filled tanks is also included in the design of aircraft? They also significantly affect fuel consumption.
When the plane is on the ground
Upon arrival at the airport, toilet tanks, regardless of the volume of filling, are emptied through a special drainage pipe. At the airfields there are sewer trucks that pump out all the contents and take it for disposal.
As for the feces that fell from the sky, this really happens periodically in different countries of the world. As a rule, there is only one reason - a technical malfunction of the sewerage system of the aircraft.
Here is what the aviation engineer Roman says about this. romadm
Madebekin in his LiveJournal: “The fact is that local leaks in the dampers sometimes cause fluid to leak outside the plane. The liquid freezes and grows, turning into a block of ice, which falls off (or not) from the high-speed air pressure. This ice is called Blue Ice (because the chemistry added to the liquid makes it blue in color). He personally witnessed when the plane arrived with an icy "beard" sticking out from under the service hatch of the water (not toilet) system. There was a slight water leak.
In Tu-154, this ice accumulated in the front toilet can break off and get into the engine. There were such cases. This is already seriously affecting flight safety. Therefore, SPECIAL attention is paid to the tightness of this damper. "
When flying on passenger liners, you may need a toilet, which you must have on board. Usually there are several of them, and the location depends on the layout of the cabin. There can be 5 and 10 of them in order to avoid queues. If you have ever flown on an airplane, then remember that sometimes you have to stand in it to get to the toilet.
In order to get rid of all waste, engineers have developed systems by which everything is removed. They are individual for different types of aircraft. We will talk about the principle of the toilet on the plane and where everything goes after that in this article. At the end, you will find recommendations on how to use it.
Much depends on passenger liners on the cabin layout, airline, aircraft year of manufacture and model.
Boeings may have them 11 or 5. They are installed at the beginning, middle and end of the cabin.
They were installed in Soviet liners 3 for the entire cabin - 1 near the entrance and 2 at the end of the tail. In small ones, it is only one, which is installed in the tail of the aircraft.
Military aircraft use sleds for everyone. Soviet bombers have toilet cabins that are taken from passenger liners.
How does the toilet on board an airplane work?
Dry closets are installed on modern passenger liners. There are tanks in the sewer system where all waste is washed off. The volume of these tanks differs on different models. On the Airbus A320, it is designed for 170 liters, and in the Tu-154, one for 115 liters, and the second for 280 liters.
The tanks are filled during the flight and removed upon arrival.
Down in the tanks certain chemicals or bags with them for neutralization and removing all unpleasant odors.
The operating principles differ from the model. So in the Airbus A320, waste is sucked into the tank by a powerful stream of air. That is why such a strong sound is produced when draining.
Diagram of the sewerage system in the Tu-154.
On other liners, waste is washed with water into tanks. Water is pumped inside before departure. Then it is distributed under pressure, which is created by air compressors, to all consumers.
There are also other closed-loop systems. The liquid that is filtered after the waste is flushed is then sent back to the toilet bowl to be cleaned again. It is disinfected for this.
When the liner arrives at its destination, a car drives up to it with a huge corrugated hose. This hose carries everything into the car. If something sticks to the sides of the tank or gets stuck inside, then both the tanks and toilets are flushed.
Waste in the car taken and poured into huge pits intended for these purposes.
Airplane drain to which the hose is attached.
You now know how the toilet is on the plane. For its use, there are special recommendations that should be followed.
Airplane toilet safety
If we talk about how to use the toilet on an airplane, then one of the main rules - do not smoke in the toilet. An alarm can be triggered which acts to detect smoke inside.
You can enter inside by simply pushing back the handle. If the handle on the door is pushed back and there is a red stripe, then the toilet is busy. If green - free.
When the plane or sits down , it is not recommended to use it - it's better to stay where you are. Go there 10 minutes before the food is served or after 15 minutes after that to avoid queues.
The toilet lid must be lowered, and then use the flush button. Throw all other waste (diapers, tampons, pads) into the trash can, since when they get inside the tank, they swell and can damage the toilet. And on board the plane it is not so easy to fix it.
No puddles should remain after you.
Today we will see what the governments are hiding from us. As we all well know, a typical airplane toilet looks something like this:
Here we see the usual things: a toilet bowl, rolls of paper, a flush button (upper right corner) and the very moment of flushing - a cheerful blue goo takes our money away. Now let's see how it all works. We will not go into the details of the design of different toilets on different aircraft, so I will only describe this toilet.
It is arranged quite simply - right under the seat there is a receiving tank with a capacity of about 62 liters. A special liquid in the amount of 12-15 liters is poured into this tank. This liquid is obtained by dissolving the powder in water - either in advance; or you can fill the tank with water and throw in two small bags. The liquid has the ability to dissolve feces. Typically, after each landing, the contents of the tank are drained into an airport lavatory service car, and fresh liquid is refilled.
Meet this tank:
A stainless steel point, a tank, hoses and some other devices are clearly visible. Fiberglass tank. The opening of the toilet is closed by a metal valve that just hangs there on the axis. If something hits it, it will open and everything will fall below, into the tank.
Along the perimeter of the toilet, under the rim, there is a flush manifold - this is a tube with holes that guides the liquid from the pump to wash the inside of the glasses in a spiral. The toilets are serviced from panels on the starboard side of the fuselage:
First, the operator of the sewer truck opens the external drain valve using the handle 1.
Then he connects a hose with a diameter of about 12 cm to the neck (there is a ball lock on the hose).
By pressing the handle 2, the stopper is removed from the inner petal of the neck and the petal opens outward, into the hose.
The operator pulls the handle (red rectangle), this opens the drain from the tank, and the contents run merrily through the pipes.
Then the suction of the machine is turned on, a vacuum is created in the hose, and all the good is sucked into the receiving tank of the machine.
The smaller hose is then connected to the flush and prime nozzle.
The tank is flushed with fresh special fluid.
The drain hose is disconnected, the handle 1 simultaneously closes the inner petal and the outer cover of the drain neck. The handle for draining the tank is recessed.
Finally, a blue fresh liquid is pumped into the tank.
Everything is ready for the next flight.
Now for some details. This is the top of the drain valve assembly:
The valve is opened by pulling the cable.
The valve itself is a rubber bulb that plugs the hole in the bottom of the tank.
Interestingly, for the front toilet, an additional ball valve is installed in the drainpipe, driven by the same cable. Rear toilets don't have that. But for the rear toilets, an additional tank is sometimes installed, where the contents of the main tank can be poured when it is overfilled.
And this is the upper part of the electric motor of the flush pump.
The motor drives the centrifugal pump, which is located inside the filter.
The filter is a mesh metal cylinder that separates large undissolved particles from entering the pump and then into the flush manifold. The filter gradually clogs up (mostly with toilet paper) and starts from the bottom.
The clogging of the filter can be easily identified by the volume of the flushing liquid - when the filter is clean, the liquid pours merrily for all 10 seconds of pump operation. When the filter is clogged, a certain amount of slurry slowly seeps out of the tank through the filter into it, and when the pump is running, this slurry first goes to flush into the point, and then, when it is exhausted, the flush stops, and the engine hums with no load.
In this case, the filter must be cleaned or replaced. To clean the filter, there is an interesting device inside it - three rotating nozzles. When filling or flushing the toilet, a special fluid under pressure enters them and is sprayed onto the inner surface of the filter. Under the action of the outflowing jets, the nozzles rotate on an axis, irrigating the entire surface of the filter from the inside and flushing out impurities from the mesh openings. But all the same, the filter gradually clogs up.
And finally, this is what the flush switch with a time switch looks like:
(there is a small box behind it with a board inside and a microswitch). The relay supplies the electric motor with a three-phase voltage of 115V for 10 s and provides a pause between repeated switching on. On this four-sided roller sits the handle that you press to flush.
The drain and filling connections are electrically heated. To prevent the remaining liquid from freezing - the sheathing is very cold at a height.
