The real reason for Airplane Mode

hi and welcome back scotty staked out info i'm scotty with my co-host Cletus who is decorated for Christmas in this video I want to talk about airplane mode so we all think that we know what airplane mode is for but it turns out that we're all wrong so obviously we all know what airplane mode is you have like say a smartphone and you put airplane mode on and all the radios are turned off it doesn't transmit or receive Wi-Fi Bluetooth there's no cell phone cellular network connection sometimes even the GPS which only receives signals from satellites sometimes even GPS is turned off on some smart phones although that's not actually technically necessary so that's what airplane mode is we all know what it is but most people say that the reason for airplane mode is to prevent your gizmo like say your smartphone from transmitting and interfering with the avionics ie the electronics and communication systems of the aircraft that you may be on it turns out that that's actually wrong now it may actually get a little bit confusing because it's kind of silly because as you know nowadays on most major airlines they have free usually free messaging like you can send text messages and that sort of thing that's free but usually you have to pay for Wi-Fi so actually if you pay for Wi-Fi you have Wi-Fi access on the airplane and yet your phone has an airplane mode to prevent it from transmitting now of course you can say well yeah but you can't use it during takeoff and landing and that's kind of a key point but the idea here is that it doesn't really make much sense to have airplane mode if you can then turn your Wi-Fi on later in the flight so what's that all about also I should note that airplane mode doesn't necessarily mean that the phone is never transmitting because most phones if you put it in airplane mode you can turn on either the Wi-Fi or the Bluetooth when it's still in airplane mode which is obviously useful if you have a flight where they have in-flight Wi-Fi you needed an airplane mode but you don't need it to totally stop Wi-Fi all of these are clues to the real purpose of airplane mode which I shall now dive into based on a wonderful document from the Federal Communications Commission if you look this up people will say oh the FAA says this blah blah blah actually it's the Federal Communications Commission the FCC that decided this whole airplane mode thing was needed and there is a very specific reason why so this document that I'm looking at here is from the FCC it has a couple different numbers on it a docket number and at the top of the page it says FCC 13 - 157 it was adopted on December 12th of 2013 and released the following day December 13 2013 and it's basically just that's basically a proposal to kind of roll back some of the earlier rulings about airplane mode and about the use of things like smartphones and cell phones on airplanes and it kind of gives us some interesting clues because they write we propose to revise outdated rules and adopt consistent new rules governing mobile communications services aboard airborne aircraft now there's all kinds of stuff in here it's kind of like bla bla bla and they note that of course this was many years old so they note that more than 40 jurisdictions at the time including Europe and Asia and Australia they've actually authorized the use of mobile communication services on aircraft but of course you have to do this in a way that is not going to cause harmful interference to terrestrial commercial wireless networks that's our first clue because later in the paper we carry on and we read in section two called background part a is FCC regulations limiting airborne mobile use and they note that this was back in the old days so they note that blah blah blah rules governing airborne use of mobile devices very significantly they talk about the 800 megahertz cellular band well that's like really really old as I said this is a very old paper but then they know there are no such restrictions on airborne use of the AWS pcs WCS 704 AWS - for bands now you may recognize such Freight phrases as AWS and especially pcs because that's like the 1.8 1.9 2 gigahertz wireless service provider so cell phone service which it's kind of been superseded now I think by by newer services but the point they're making here is that this 800 megahertz cellular band which was very old that one was regulated but all the newer ones were not regulated so obviously they have to update this and then they note this is the key part part 22 of the Commission's rules prohibits the airborne use of 800 megahertz cellular telephones including the use of such phones on commercial and private aircraft this prohibition was adopted in 1991 to guard against the threat of harmful interference from airborne use of cellular phones to terrestrial cellular networks the Commission's prohibition was not to ensure interference free operations of avionics equipment when the prohibition was adopted the Commission noted that a cellular telephone used on board an aircraft would have greater range than a land-based handset and its signal would be received by multiple terrestrial cell sites in a given market causing harmful interference moreover the Commission found that because the cellular telephone can transmit on all assigned frequencies a single handset could interfere with cellular systems in multiple cellular market areas simultaneously thus the Commission concluded way back when 1991 that the need for non interference in all cellular transmissions outweighs the benefits that would be real by allowing the public to use cellular service in airborne craft so what the heck does that all mean basically way back in 1991 when most cell phone providers were using like this 800 megahertz band and and back in 1991 everyone wasn't running around with even a cellphone much less a smart phone the FCC not the FAA not the airplane group but the Federal Communications Commission got together and they said hey look we can't have this and the reason is mostly it's about something called handoff so when you have a phone or smartphone you're connected to a cell tower now if you start moving your phone actually will connect first it's connected to this tower but as you're moving this way it connects to the next tower and there's a time when your phone can actually be connected to multiple towers at once and they're kind of negotiating and the phone is detecting okay which which tower do I have a stronger signal from and and the towers are kind of it's there it's basically working out that's sort of a network level okay who who should this who should your phone which tower should your phone be connected to so as you move along first you're connected to this tower as you move along then suddenly you're closer to this tower so your phone connects to this one and drops its connection to that one and it's constantly checking to see ok which tower should I connect to now you can imagine if you're on an airplane that's traveling say faster than 200 miles an hour which somewhere in here it's mentioned that's sort of the key speed if you go faster than 200 miles an hour imagine how quickly that handoff would be occurring you'd be connected to this tower than this tower and this tower in this tower and of course that can overload the cell phone system at least it could back in 1991 furthermore if you're in an airplane you've got powers down here and your airplane is up here now your signal from your phone that you're using on the airplane is actually transmitting signals down to the ground and of course it has it's not really the proper angle but of course it would have kind of line-of-sight and sort of a more clear transmission path to all these towers in the ground which means not only is your plane flying really fast and it's trying to hand your phone off from this tower tower to this tower but your signals are actually flooding a very large geographical area and you could even be connected to multiple carriers and multiple towers and basically that would overload the system at least it would back in 1991 that's the idea so that's why they banned the use of cell phones on airplanes it wasn't interfere with the avionics of plane it was to prevent problems with the cell phone networks on the ground now of course today we have much newer systems and they're much higher capacity we have crazy data and of course things have changed and as I said this paper is from about five years ago and nowadays yeah we've even have like Wi-Fi and stuff on airplanes and you can even make phone calls sometimes you can do text messages it depends on the airline it depends on the services they provide so okay well how does that actually work because you know obviously as I said before you can have your phone in airplane mode but you can still enable the Wi-Fi will that make sense because they offer in-flight Wi-Fi and the way that they do this is the airplane actually has a couple and one or two antennas on the airplane itself that connect wirelessly to a satellite actually to multiple satellites as the plane travels that's actually the internet connection it's kind of like satellite internet for an airplane if you've ever had satellite internet you know you have a parabolic dish that's wired up to your house tier that's your internet and it shoots the Rays way to hook up to a satellite the satellite bounces it back down to a base station on the ground and you can get very high download speeds even though the latency is very high because it takes a very long time for the signals to go way up to the satellite and when you back down to earth so that's what they do on airplanes is most of the time there are some airplane to ground links but nowadays there's a service called I think it's called gogo and it's basically internet by satellite so the airplane itself has it has a internet connection essentially via satellites and then within the cabin they have very low-power Wi-Fi and this is one of one of the key points is if you have multiple antennas in the cabin you can have their transmit power set very very very low and then as I mentioned in that video about reducing your Wi-Fi transmit power anyway they set the transmit power inside the cabin the transmit power of the Wi-Fi very very low and of course you're all just sitting there in your seats and you have your Wi-Fi gizmo and your device is also transmitting at a very low power because it doesn't need to transmit it a very high power and it's only Wi-Fi ok so there you go that's that's how that works now obviously if your phone is in airplane mode it's not connecting to the cellular networks that's why we kind of still need airplane mode because you still don't really want a cellphone a smart phone on a plane connecting even to modern cellular networks because you may have similar problems so they say yes put your phone in airplane mode that kills your cellular connection it eliminates any problems of connecting to stations on the ground and then they say oh but if you want messaging or Wi-Fi or something you can re-enable Wi-Fi now sometimes Bluetooth and then you can connect via the onboard Wi-Fi on the plane which connects by a satellite back down to earth to the actual internet but they still actually have rules in place where when the plane is taking off and landing you're still supposed to stow all your electronic devices put your seat back and tray tables in the upright position and all that kind of stuff and the reason for that is pretty simple it's probably fairly unlikely that even a bunch of cell phones would cause interference with the avionics it's possible but it's probably unlikely but generally speaking it's kind of a bad idea if your plane is at rest and it starts to accelerate and go really fast and take off everyone's phones on the plane are connected and they're they're you know they're trying to connect to cell towers and maintain their connection now obviously there are probably many people on your average flight who are told to turn their phone off or put it in airplane mode and they forget and to my knowledge no planes have crashed because someone didn't put their phone on airplane mode but the point there is that generally during takeoff and landing you do want to turn all electronic things off you want to put airplane mode on you do want to put your seat back in the upright position your tray table put your seat belt on because takeoff and landing are actually the probably most difficult in most dangerous parts of any flight you have to worry about other airplanes you have to they basically lock the whole airplane down because it's like a hairy part taking off landing when it's flying up in the air that's like almost easy compared to taking off and landing so you know even even the the air host I'm not even sure which the people who work on the airplane and serve you drinks and food I'm not sure even what the politically correct term is these days those those people they actually have to sit down on their seats and strap themselves in and so so that's why we still have that kind of thing it's it's not really like it's gonna destroy the cell phone network but it's just kind of good practice like better safe than sorry and once you're actually in the air these rules for like when you can use Wi-Fi and this and that there are specific rules you have to be like above 10,000 feet if you're going faster than 200 miles an hour then you have to do this and you have to have a they call it a Pico cell where there's this essentially like I explained the the Wi-Fi on board in the cabin of the aircraft that's actually connected to the satellite connection and that's sort of the approved way of doing things so obviously simply having Wi-Fi enabled on board and airplane is not going to cause the airplane to crash and the key the key problem here that dates all the way back to 1991 was the fact that in those early days cellphones could have kind of screwed up the the cell service on the ground because the plane had such a wide sort of a wide-angle bird's-eye view of all these towers and providers and also because the speed that the aircraft was traveling and because of his hand off problem and that whole thing just sort of got carried over until today and yeah so that's a that is actually where airplane mode came from that's why you're not supposed to use a cell phone on an airplane and right there you go for more techie tipsy Scotty's take that info thanks for watching and see you next time

Channel: ScottiesTech.Info

Views: 296,111

Keywords: airplane mode, flight mode, smartphone, wifi

Id: MlPrd7MLsAk

Length: 15min 28sec (928 seconds)

Published: Tue Dec 18 2018