I would suggest that this is actually more efficient.
When people use the toilet on planes, the design of the toilets uses so much less water than a toilet on the ground, in the airport, and how much a flush of water takes.
So if you assume that people were going to use the bathroom regardless, they just saved the processing of a lot of water by doing it on the plane. Probably ounces versus gallons. (~100 mL vs. 1-2 L)
(parenthetical note, sometimes I wonder if a vacuum toilet would become available for home use, it's so effective!)
Now certainly, flying around to use the bathroom used up a lot more energy, but regardless... Also, you might ask whether people tend to drink more than average because they're offered drinks on a plane.
I used to wonder, considering the hundreds of pounds of water/soda/etc loaded on a plane, as people drink and consume it all, wouldn't it be efficient for the plane to dump that water in flight and save the weight and extend the range. Turns out (of course) that is so negligible compared to the overall weight of the plane...
> parenthetical note, sometimes I wonder if a vacuum toilet would become available for home use, it's so effective
I've heard it said that plumbing issues dramatically increase with modern, water-efficient toilets. It's not hard to imagine why. Sewer usage and maintenance are at a far lower rate, so stool will settle and clog when ever smaller amounts of water are introduced.
I'm not sure this problem can be solved, assuming regular sewage as the method of disposal.
A lot of problems are also due to old systems. Ask any plumber. The plastic pipes are smooth inside. Old pipes weren’t only rough, they degrade. Cast iron sloughs off into itself. There was a kind of pipe that was used that was basically tar paper; it broke down and clogged itself (like cast iron).
A new building with new toilets should work very well. Replacing your toilet may not help if your pipes from the 60s are basically nonexistent.
Orangeburg pipe is the tar paper stuff. It's a time bomb. Not only does it break down with use it also flows (flattens with gravity/overburden pressure, bends over unsupported sections run through walls/floors, etc) over time as well, especially in a hot environment. So even if it doesn't get much use it will collapse and/or stretch and break.
Indoor pipes still can be horizontal for long stretches, where smoothness doesn't help if it's flushed only a few times per day. It also depends on the stool. I never cause obstructions, but my wife on the other hand...
Drinking in a plane is also note necessary because the air is pretty low in humidity. It sometimes even gives me nosebleeds on long flights.
However I mean non alcoholic drinks of course, alcoholic ones dehydrate even more. I rarely drink alcohol on planes for this reason. But this is often what people drink because it's free.
Yup. liters makes it sound like a big number, but using the author's example:
>> The world’s busiest airport by passenger volume, Guangzhou, could have handled 5.14 million litres of pee in April 2021.
That converts to about 43k 55-gallon barrels per year, or about 118 barrels per day. An insustry standard oil tanker truck is about 210 barrels, range 50-300 [0]. So, all in all, pretty manageable.
That’s true, my small city processes the waste from over a million people (they provide sewer to the suburbs) every day which is about the same as the number of Americans who fly. Plus they process all the other water that goes down the sewer from showering, laundry, etc. So just one small city is probably processing much more than all the planes in the country combined.
I haven't had to take a dump on an airplane in years.
My rule is to eat and drink as little as possible before a flight, ideally not eating at all. If I do eat, hopefully it's high protein and low in fiber. As a result I usually don't need to use the lavatory, which is nice because it has made me much less apprehensive about getting a window seat.
I wish more people had this mindset. On so many flights I've had, seemingly half the plane is ready to take a shit. My only explanation is that they're overnourished on the Standard American Diet. Imagine how much less waste would have to be pumped out of airplanes.
* My only explanation is that they're overnourished on the Standard American Diet. Imagine how much less waste would have to be pumped out of airplanes.*
A lot of folks poop on a schedule: Making sure you don't poop on the plane might very well involve adjusting food for a few days before a flight, depending on how often you poop. Some folks poop multiple times a day, some folks poop a few times a week. Some women poop more during their monthly cycle, too - which, by the way, does not happen at the same time every month nor do you always have notice.
You'd be able to eat not too long before the flight, though, if you are healthy simply because most folks don't process food too terribly fast (but the timing varies). Adjusting what you eat for days just isn't worth it, and not everyone can do this.
Also, not everyone on the flight is going to be American, but the chances are higher if you are taking in-country flights in the US. I personally don't encounter many Americans on flights - I'm often the only one. But then again, I don't live in the US either.
But that's exactly the reason why healthy people,
whatever healthy means, should starve:
If those who can control their asses do so,
then there are more toilets available to those in need.
Holding back on food is fine, but you should try to stay adequately hydrated while flying, especially longer flights where you may be more susceptible to deep vein blood clots.
OK that first sentence was the line I have least expected to start a Hacker News comment ever. Also you are correct on all counts. I developed these same techniques to avoid peeing during the opera but they ported well to air travel.
I can't even understand why people are eating/drinking in planes, I haven't take a flight since several years but usually you've a bit of adrenaline, thus no hunger
If you're not used to flying (like yourself) this might be the case. For regular flyers (like me) it's often more like taking the subway or commuting to work. Personally I always get an aisle seat, take at least two liters of water with me to combat the dehydration and let me get to work/family/whatever in the best shape I can be when I land. I always eat ahead of time or at the airport (lounges make this more reasonable) because I also know that on the other end of the flight there's baggage, a taxi, checking into the hotel, getting to dinner, etc. So figure at least two hours of hassle before a dinner or snack is possible, usually more.
Flying dehydrates you - the cabin is pressurized by constantly pumping outside air into the pressure vessel that is the fuselage, and the air at cruising altitudes is extremely dry in addition to having less oxygen than we are accustomed to at ground level. We increase our respiration rate due to the lower oxygen content, and lose a fair amount of water in the process as the dry air drains it from us.
I've never been on a flight long enough that I needed to eat, but even on a regional flight I find myself wanting at least something to drink because my throat feels a little dry.
I fly small planes and I'm usually into a snack bar before I level off. I do try to make one liter of water last the whole flight, though, which can be up to 5 hours.
Never took a dump on a plane, but I hate airports, and usually find myself at the bar before boarding which more than often has led to a painful urge to pee at the worst times.
I like articles like this that encourage you to think about details that are often missed when it comes to making everyday life run smoothly. I also get that it makes sense to time box it to a year to give a sense of scale to the problem. However the headline is written in a click bait-ey way that rubs me the wrong way. I know you gotta do it for the clicks and all, but I think we need to find a better way to capture the attention of readers.
Two billion litres a year. Impressive number at first glance. But let's say my own household of 4 was able to keep water consumption down to 500L/day (I wish), that's already around 180K litres/year just for my house. So divided into 2B, that's about 11K houses' worth of wastewater. A modest size town's worth, for all the air travel worldwide.
It seems very likely to me that they carry more than 1L of fluid per passenger, plus there's also the crew. So yes, they could :)
Of course, if they dump all their drinking water, it'll be hard to reach the maximum pee capacity per passenger. But you could always resort to dumping food.
The onboard tank capacity is probably one of those things that needs to be overprovisioned so it practically never gets full. You want to run out of fuel and have to divert more often than run out of space in that tank.
First of all, all that pee is on the plane when it lifts off, in one form or another. The only thing that changes is distribution of mass (depending on where the tank is and where they keep bottles with drinks). A tonne of pee gathered from all over the plane is most likely less effect than 3-4 people moving from one end to another end of the plane. So a stewardess with help and a cart.
Second, pilots can trim the plane while in flight.
Third, no safety margin is needed here because this is not a safety problem.
The amount of pee that can be deposited into the tanks is limited by the amount of pee they can physically hold at the start of the flight plus the amount of drinks they can consume during flight.
But more realistically, on a long flight, it is just the amount of drinks they can consume assuming they drinks are mostly used to replenish whatever they have peed. Most people try to empty their bladder before flight and are willing to have full bladder when they leave the plane (to relieve themselves afterwards) so I think even this is already a little pessimistic.
On 747-400 you have max 660 passengers. 1135L divided by 660 passengers gives ~1.7L per passenger on average. Which is a lot. Consider this is an average -- some people may drink way more than that but most people drink less than that in a day.
So it seems it might be possible to run out of the tank -- if you have a very long economy flight in a large plane converted to densest possible seating arrangement and if you are willing to believe people will be buying over 1.7L of fluids per person on an economy flight.
Of course, all that calculation goes out the window if you plan to fly an economy flight full of Australian Oktoberfest fans directly from Germany to Sydney.
> Third, no safety margin is needed here because this is not a safety problem.
Sewage overflow is certainly a safety problem. Just health safety though, not flight safety.
1.7L per passenger is a large volume of excretions, but flight operations may require multiple flights before emptying the tank, especially if there's a problem with the emptying equipment at some airport. Would a failure to empty the tank prevent a plane from taking off? Probably only if the remaining capacity is likely to be insufficient.
> The only thing that changes is distribution of mass (depending on where the tank is and where they keep bottles with drinks). A tonne of pee gathered from all over the plane is most likely less effect than 3-4 people moving from one end to another end of the plane. So a stewardess with help and a cart.
My informal search [1, 2] seems to indicate that every galley seems to have WC close by, though not vice-versa. Would never have thought to attribute that to an engineering decision before this discussion!
I imagine they have less than 1135 litres of beverages on board, which helps. Also 40k litres of fuel, much of which gets used up over the course of the flight...
> how much safety margin does the tank have build in
From the article: 1 liter (747) to 2 liters (A380) per passenger. More than enough, even if a dozen people manage to catch the runs and eject more liquid.
> how would an almost full tank affect flight behavior
Not that much, pilots can (and have to, as part of weight redistribution caused by the fuel tanks emptying) "trim" the airplane - basically, applying an offset to the neutral position of control surfaces (see https://en.wikipedia.org/wiki/Trim_tab). And all the content of the toilet waste tank was already in the plane before (either in the bodies of the passengers, or in the freshwater tank), so it's only a minor distribution change.
I imagine they use the same chemicals as marine toilets / portapotties. It breaks down poop and toilet paper into a liquid so that it can be pumped / emptied easily. Not sure why the article focuses solely on urine...
That has the downside that a penny-pinching passenger might attempt to "hold it in" and then, shocked by a turbulence, involuntarily ejecting what was "held back"... leading to the plane needing an extra cleaning or being taken out of service.
There's a reason why even Ryanair, otherwise the leader in borderline unethical airline behavior, quietly buried their 2010 attempt to introduce a loo charge [1].
Another reason could be due to smokers. There's a reason toilets on airplanes still legally need to have an ashtray - there's still people who are willing to break the rules to have a fix so it's safer to at least provide somewhere safe to put a cigarette out.
Charging for the toilet could just encourage those same people to light-up in the main cabin.
I'm reasonably certain Ryanair was never serious about that. They like to make outrageous announcements anytime they think they are not getting enough attention for being the cheap airline.
I disagree that they're unethical. The deal you get with Ryanair is the ticket is as cheap as possible, then they nickel and dime you. A lot of people want that. A lot of people want better service, and they can go with a legacy carrier.
Do not give them any ideas, flying is miserable enough as it is. But here is another idea which maybe Airlines can do to make flying even more horrendous.
Eliminate the bathrooms and make everyone wear Depends. I would not be surprised this happens. The bathrooms could be replaced with a few seats and they save money by forcing people to clean up themselves :)
I now refuse to fly, I would rather drive or take a train or even a bus. Of course with covid driving is probably the better option if you can spare the time.
Of course I heard many people now drive instead of fly, which is making medium travel distances (say under 1000 miles) not enjoyable. Never mind the CO2 being pumped out.
Again the US needs a good public transportation system, which of course will never happen. If pols just stop talking about this, it would probably lower CO2 emissions from all their hot air they are expelling.
When people use the toilet on planes, the design of the toilets uses so much less water than a toilet on the ground, in the airport, and how much a flush of water takes.
So if you assume that people were going to use the bathroom regardless, they just saved the processing of a lot of water by doing it on the plane. Probably ounces versus gallons. (~100 mL vs. 1-2 L)
(parenthetical note, sometimes I wonder if a vacuum toilet would become available for home use, it's so effective!)
Now certainly, flying around to use the bathroom used up a lot more energy, but regardless... Also, you might ask whether people tend to drink more than average because they're offered drinks on a plane.
I used to wonder, considering the hundreds of pounds of water/soda/etc loaded on a plane, as people drink and consume it all, wouldn't it be efficient for the plane to dump that water in flight and save the weight and extend the range. Turns out (of course) that is so negligible compared to the overall weight of the plane...