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WiFi without internet on a Southwest flight

jamesbvaughan.com

201–210 of 675 posts

Re: WiFi without internet on a Southwest flight

#202
post #200
post #136

“According to this data, the plane’s altitude was only fluctuating by about 20-30 feet. This is more stable than I expected!” Autopilots are very good and they are servoing to the pressure altitude. Many pressure altitude encoders used in modern aircraft (for example to drive altitudes that transponders report to SSR radar or via ADS-B) have 25 ft encoding resolution. That 25ft resolution is likely what is being seen…

A plane going up and down 20-30 feet seems like it would be very unpleasant. Considering that there's longitude and latitude, isn't it more likely that the altitude is coming from GPS, which is notoriously inaccurate with regards to elevation?

Maybe the plane is staying level but the ground is variable terrain.

Re: WiFi without internet on a Southwest flight

#203
post #179

Earlier quoted context omitted.

Someone will probably figure out how to send a request to disable auto-pilot or turn off the fasten seat belt sign.

the airline industry is nowhere nearly as stupid as the software industry with things like this. the communication between plane and wifi/entertainment system, if there is any, is almost certainly one-way. likely, the wifi system providing this info is receiving data from the flight systems and repeating it or transforming it a bit and providing that. it would not surprise me at all if the flight attendants have to p…

IIRC the in-flight infotainment systems are entirely separate from the avionics control systems at the data layer. I recall being told that in some cases even the flight status is actually pulled from a 3p api service rather than hooked into the onboard avionics.

There could be some fuckery via shared power or other non-data systems but that’s probably beyond someone sitting in a seat with standard laptop hardware.

Re: WiFi without internet on a Southwest flight

#204
post #18

Earlier quoted context omitted.

Hi fellow Alaska frequent flier. So about that! There's this iOS app called Flightly that does a brilliant little hack where the app updates itself in (almost) real time on the "free messaging" plan. The way it works (according to a friend) is that their servers send your phone a push notification every couple of minutes from take-off until landing, containing some serialized info such as lat,long,alt,eta,etc. And th…

> There's this iOS app called Flightly I guess it's Flighty ( https://apps.apple.com/us/app/flighty-live-flight-tracker/id... ) I love that people are into this. In the days before iPhones, I had "Microsoft Streets and Trips" + a USB GPS unit + Laptop. It was fun having it on a flight and seeing movement data in realtime. It was less fun answering questions from people who thought looking at the GPS data was somehow…

Ha! I've used a high-end GPS to see my location and other fun facts in flight. I learned to keep it in my pocket as despite my attempts to explain it was only a receiver, I was told by the flight attendant to "PUT IT AWAY." Not being one to push back as to be removed for that flight, I did just that.

Streets and Trips was fun on a laptop for long car drives as you could live reroute in the car much like any old app can do these days but seemed somehow magical back then.

Re: WiFi without internet on a Southwest flight

#205
When my son was younger - maybe 9 or 10 or so, we were on a plane and he was using his phone and I looked over his shoulder and realized he was on the internet... but I hadn't paid for an internet plan. I said, "son, how are you using the internet?" He said, "oh, a kid at school showed me - if you go here" (he opened up the wifi settings where the DHCP assigned IP address is) "and start changing the numbers, eventually the internet will work." Apparently, at the time, on American Airlines, when somebody bought and paid for an internet plan, it gave them an IP address and authorized it to use the internet... if somebody else guessed your IP address (which was pretty easy, it was a 192.168 address) and spoofed it, they could take over your internet connection with no further authorization.

I had to tell him not to do that, but I was kind of proud of him for having the temerity to go for it.

Re: WiFi without internet on a Southwest flight

#206
post #85

I want to see someone build a proxy that uses the free iMessage or WhatsApp allowed connection to send arbitrary data. Like have a WhatsApp relay set up at home that you are sending messages to and from, from the plane. Like at a most basic level, send a message of a URL to your home WhatsApp which loads the web page there, and sends the HTML back as a WhatApp message reply so you can render it etc. Wonder what someo…

I've noticed that airline wifi doesn't block DNS traffic. You can likely accomplish the same thing with a DNS tunnel like Iodine ( https://github.com/yarrick/iodine ).

Many years ago, I noticed I could browse the Google Play Store on a flight WiFi without paying for it. No images would load and no apps would download, but I could browse through app listings and read reviews.

Would this be related to DNS?

Re: WiFi without internet on a Southwest flight

#207

I'm an Alaska (relatively) frequent flyer. That airline offers a free "messaging" plan, that lets you send and receive messages on apps like iMessage, Facebook Messenger and Whatsapp. Though, it somehow prevents images/attachments from coming through on those platforms. I've always wondered how this is implemented technically, and if it might be possible to setup some kind of protocol/wrapper to send data that looks…

Do they allow Telegram? If so, that would be the easiest, Telegram has a really good bot API.

Many do but some don't. I wrote an HTTP Proxy for Telegram and it works fine for those situations but is very slow. I prefer using an NNCP proxy I wrote because the protocol doesn't have online liveness requirements.

Re: WiFi without internet on a Southwest flight

#208
post #200

Earlier quoted context omitted.

A plane going up and down 20-30 feet seems like it would be very unpleasant. Considering that there's longitude and latitude, isn't it more likely that the altitude is coming from GPS, which is notoriously inaccurate with regards to elevation?

Maybe the plane is staying level but the ground is variable terrain.

Elevation is relative to sea level, not the ground.

Re: WiFi without internet on a Southwest flight

#209

Here is how to get the equivalent data on a Delta flight. $ curl https://wifi.delta.com/api/flight-data | jq % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 100 448 100 448 0 0 5600 0 --:--:-- --:--:-- --:--:-- 5743 { "timestamp": "2023-07-11T14:54:41Z", "eta": "17:48", "flightDuration": 278, "flightNumber": "DAL786", "latitude": 39.723472595214844, "longitude": -97…

[deleted]

Re: WiFi without internet on a Southwest flight

#210
post #136

“According to this data, the plane’s altitude was only fluctuating by about 20-30 feet. This is more stable than I expected!” Autopilots are very good and they are servoing to the pressure altitude. Many pressure altitude encoders used in modern aircraft (for example to drive altitudes that transponders report to SSR radar or via ADS-B) have 25 ft encoding resolution. That 25ft resolution is likely what is being seen…

I guess they got a lot more precise with implementation of Reduced Vertical Separation Minimum (RVSM) - planes had to be separated by 2000 ft and this was reduced in early 2000s to 1000ft
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