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Kind: captions Language: en most plane doors aren't locked there are no keys No sensors or passcodes to secure them if someone wants to pull the lever they can a man opened the emergency exit door and forced his way off the plane and yet with 40 million flights each year these doors are virtually never opened in flight so why not your self-preservation surely Common Sense most people are you know smart enough to not mess with that the real answer relies on where planes fly how high do planes fly approximately 10,000 km or is that overshooting it I think that's overshooting it I think you'd be in space 25,000 km that's the height of a plane flying is that way too low it's too much it's it's too much too much too much bring it in maybe 1,000 km 1,000 km still space 50,000 fet I think some of them can go up to 43,000 Ft 30,000 ft 38,000 ft yeah yeah why do they fly that high uh I don't know safety I guess probably to avoid um collision with other aircrafts and if there's high mountain ranges I don't know when the When Storms or or or weather hit my guess is to avoid a turbulent weather I think that's a decent guess now it's true that one of the benefits of flying at 30,000 ft is a smoother ride this is high in the troposphere the layer in which most weather occurs so there's less turbulence and fewer storms to navigate around but this is not the main reason that planes fly so high the bigger reason of course is money as you go up the density of air decreases and at 33,000 ft or 10 km the density of air is just a third of what it is at sea level so flying at this altitude the plane runs into a third of the air molecules it would closer to the ground that means the plane can fly about 73% faster for the same amount of thrust and as a result you get to your destination faster and since you spend less time in the air you burn less fuel it seems in a way that like climbing is wasted energy can you compare like The Descent to the ascent do you essentially get the energy back as you fall down the other side yeah when we climb we burn about 80 kilos per minute in cruise we burn about 40 kilos per minute and in descent it's maybe 10 so it's almost negligible not only that jet engines are more efficient at altitude they work by compressing Air at the intake mixing it with fuel and igniting it so the combustion products are ejected very fast from the exhaust nozzle now this process is more efficient the colder the air is and at altitude the temperature is around -50° cus which is a lot colder than an average of plus 15 here at the ground so flying high means you burn less fuel for less time and avoid the weather and Associated turbulence of lower altitudes the other reason you want to fly high is to take advantage of the jet stream Tailwinds and the company likes people who do that because you're burning less fuel such less less money but there is a problem with flying this High the air up there is unbreathable if you were suddenly teleported to the top of Mount Everest a height lower than planes fly you you would remain conscious for only about 3 minutes this is because in addition to density dropping with altitude so does air pressure air pressure actually falls off faster because it depends on the weight of all the air above you so at 10 km the air pressure is only a quarter of what it is at sea level to be clear the air is still 21% oxygen but the partial pressure of oxygen the pressure exerted solely by oxygen molecules is around 5.5 kilop Les which is a quarter of what it is on the ground now at this pressure not enough oxygen molecules can force their way into your blood in your lungs to function normally humans need an oxygen partial pressure of at least 16 kilopascals so all the cabins of airplanes that cruise at high altitude must be pressurized a little bit of air is continuously brought into the cabin from outside it actually comes in from the compression stage of the jet engines that is what maintains breathable air inside the plane the downside is that you are taking away a little bit of the efficiency of the engines now pressurizing the cabin required a radical redesign of aircraft before pressurization planes would fly up to 10,000 ft or around 3 km where the partial pressure of oxygen is 15 kilopascals just at the limit of what people can handle on these planes doors opened outward and there wasn't much concern about the seal around them since the pressure was the same on both sides but once planes were pressurized all the doors were changed to be the shape of a plug they're wider on the inside than the outside that way the higher pressure inside the cabin pushes the door into its frame creating an airtight seal how airtight is a cabin it's pretty airtight but not completely airtight so you'll notice for example every time that someone flushes the toilet you'll see some of the air pressure go down so every every time that happens you can actually see the cabin altitude jump a little bit and this is why plane doors and emergency exit doors don't need locks the difference in pressure between the pressurized cabin and the low pressure exterior is so great that no one is strong enough to pull the door inwards and if someone had come up and turned that wall your mid-flight nothing even modern plane doors that open outward are shaped like plugs they're just just cleverly designed the main passenger door on a Boeing 737 is both wider and taller than the frame it needs to pass through but when you pull the lever gates at the top and bottom fold in reducing the height just enough however the sides are still too wide so the door first has to pop inside and rotate it's that movement inwards that is impossible at altitude it would require a force equivalent to lifting 9,000 kg and airplane cabins aren't even fully pressurized to the sea level pressure of 101.3 kilopascals you may have noticed this if you take a bag of chips on a plane it's easy to squish on the ground but as the plane climbs the pressure in the cabin drops and the chip bag seems to inflate like a balloon I measured the pressure in my plane and at cruising altitude the pressure dropped to 77 kilopascals meaning the partial pressure of oxygen was only 16 kilopascals the minimum required for people on the plane to feel normal this has some unintended consequences do you think you fart more in a plane if I did I'd blame someone else I feel like no no no I can't let a rip no way in the world do you think you fart more in a plane than on the ground 100% no hesitation sure I mean it's got to do with the cabin pressure right so as you go up that cavity in here now expands and the air wants to go somewhere and the quickest place it can go is South me chips just pared by itself now the International Space Station is pressurized to sea level pressure 101.3 kilopascals so why are planes pressurized to the minimum extent possible to carry human passengers well it's actually for a very good reason in 1988 Aloha Airlines 243 was on route from Hilo to Honolulu Hawaii the cabin was being pressurized as we've described but unfortunately this plane's fuselage had a small crack and all of a sudden at 24,000 ft the crack widened and the whole roof tore off the front of the plane miraculously the pilots were able to land safely and only one person was killed the difference between the International Space Station and a plane is that the ISS was pressurized once and it stays pressurized but a plane experiences a pressure difference every time it climbs to cruising altitude so the fuselage is stretched and then relaxed with every flight stretched and relaxed stretched and relaxed the Aloha Airlines plane had the second highest 737 flight cycle count in the world with nearly 990,000 in total that's way more than it it was designed for this led to fatigue cracking corrosion and the eventual explosive decompression so planes are pressurized to the least extent possible to minimize stresses and extend the life of the plane but even 75% of atmospheric pressure should be plenty to prevent the doors from opening so how did this happen in May 2023 a passenger panicked and and actually managed to open Airbus emergency exit in flight they were on Final Approach then they were quite close to the ground so the pressure differential was very little and because of he him using all of his Force he actually managed to get the door open which was crazy and we didn't think that that was possible but if you want something bad enough I guess it is wow was he okay he was okay everyone was okay in that case that was a pretty serious mishap so I guess the next logical question is have any other passengers inadvertently caused a mishap by say forgetting to put their phone on airplane mode when you're sitting there in the tarmac and they come on and tell you to put your phone on airplane mode do you do it and why why do they get us to do that what is the reason is there a reason obviously they wouldn't asked you to do it if it wasn't for some benefit I'm unfortunately a bit of a rebel and I don't follow the rules and Y but you're not worried about taking the plane down I'd make sure my my parents have the airplane mod on so I can have it off I mean yes I do because I don't want to interfering with like the radio or whatever well I think it's the um communication interference I feel like I've always been told like it messes up like instruments but honestly they're always just told to do it so you know just got to put your phone in airplane mode in 1961 the Federal Aviation Administration or FAA found that some portable FM radios could interfere with plane navigation systems since they used neighboring radio bands and out of caution they banned almost all personal electronics on flights but Airlines could test any device for interference and overrule the FAA ban to allow it on board any device that is except a phone because another organization has jurisdiction over phones and that's the Federal Communications Commission or FCC see a phone on the ground with buildings and hills around it can usually only see one or two cell towers at the same time but from the air it could see 10 or 20 or more the concern was that 200 phones traveling at 800 kmph in a plane could rapidly connect to many Towers at once overloading the infrastructure at least that's what the FCC thought could happen so they banned cell phone use in Flight in 1991 but there's a problem with this Theory a plane is a a big metal enclosure essentially a faay cage so it should block almost all electromagnetic signals that's why plane antennas are located on the outside your phone signals can only Escape Through the Windows which means they go horizontally out the sides of the plane so they would have to travel long distances before reaching the ground and the cell towers your phone is trying to connect to well they are tilted downwards you know to collect all the signals from people walking around on the ground so it's very hard to make a connection from the air unless you're flying really low so phones could only conceivably disrupt ground networks during takeoff or landing and the FCC never even tested if this was the case in 2005 they went before Congress and said the rule Banning 800 MHz cell phone use in Flight may not be needed in order to protect groundbased cellular networks as far as we know a mobile phone has never caused an air accident all airplane mode does for sure is save your battery life so why are these rules still around I've been flying myself and where I've gotten interference you know when you're talking to a traffic control and you get that you know that signal and that is because someone is either using their phone or the phone is on will one uh phone in an aircraft cause any problems probably not will 200 do something maybe rather than taking the chance of like let everyone update their Twitter profile at 500 ft rather than saying that we we're saying no you know just keep them off you know enjoy the Wi-Fi up at altitude and and that's it but airplane mode might soon be a thing of the past the EU actually no longer requires it and is pushing for Airlines to provide 5G service on all EU flights so we may eliminate that inconvenience but we still have to deal with airplane food what do think about airplane food I only eat the bread rolls that's anything I can handle from that everything tastes like mush it can not be very good it can be very terrible H blish different consistency do you think the food tastes as good in a plane as it would on the ground no but bad tasting food might not be all the airline's fault see the air that's pumped into the cabin at altitude is really dry I mean the Sahara Desert for reference has an average relative humidity of 25% but inside an airplane cabin it can be as low as 5% this can dry out your nasal passages hindering your sense of smell and therefore taste the lower cabin pressure can also decrease Sensations like the intensity of salt and sugar but there is one flavor that appears to be enhanced in Flight what do you drink in an airplane what's your drink of choice apple juice apple juice interesting I mean Coke that's default orange or app apple juice jit and tonic maybe a bloody mary if if uh you're the first one today really yeah a German survey of a thousand Flyers found that more than a quarter of them ordered tomato juice in flight and what's really weird is that 23% of those people would never drink it on the ground and would you drink Bloody Mar would that be like a standard drink at the bar or is it a special plane drink I only have it on planes so why is everyone ordering tomato juice well it could be because of the noise a 2015 study points to the Corda Tony a nerve that carries taste information from the tongue to the brain stem it runs right past the eardrum between the tiny sound conducting bones so loud cabino might unintentionally stimulate it this could produce an audio illusion that boosts our sense of umami the Savory taste you find in MSG soy sauce and well Tomatoes I always drink tomatoes juice and I never knew why it just felt like my plain drink or like spicy tomato juice like both of those are favorites of M yeah so next time you're on a flight go for something extra sweet or salty or maybe try the tomato juice I feel like with how much people fly our perspective of flying is still pretty distorted so why is that yeah I know that we talk a lot about accidents and incidents and we dig into them really really deep and people might ask why would you be doing this doesn't that just make people even more afraid of flying but the fact is that this is one of the Prime reasons why Aviation is as safe as it is the fact that we have hundreds of professionals that dig deep into these accidents means that we learn from them so every flight becomes a little bit safer that's actually a big reason that I started my channel Mentor pilot in the first place cuz I promise you the more you know the safer you'll feel do you think that climate change increases turbulence depends on what people think their opinions uh it's been a bit without any news recently how's in there today the media tends to prioritize sensationalized headlines over key details part of why airplane mode is still such a big deal today is because of the media frenzy it started in the 1960s so it's more important than ever to look at all sides of the story this is why we specifically asked ground news to sponsor this video recent stories about the increase in turbulence come from a 2023 study that suggested a link to climate change yet this study was barely reported on by the media totally eclipsed by other major events but ground news lets you see the whole picture you can easily compare the coverage and verify the source of the information if you look closer you'll see that some of the outlets like the independent and the scmp argue that climate change is making flying more dangerous While others like the Free Press paint a different picture by dismissing the study that's why it's really important to look at all the information but ground news doesn't only highlight breaking news on things like science and Aviation they also specifically show Blind Spot Stories the media isn't covering veritasium is all about getting to the truth and ground news mission is to provide all sides of every story so that we can do that for ourselves so I encourage you to check them out at grounds.com the link is below or you can scan this QR code make sure to subscribe through our link to save 40% off unlimited access and by supporting ground news you're not only getting a tool we need now more than ever but you're directly supporting this Channel and our work in the meantime so I want to thank ground news for sponsoring this video and I want to thank you for watching
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