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WiFi without internet on a Southwest flight

jamesbvaughan.com

221–230 of 675 posts

Re: WiFi without internet on a Southwest flight

#221

Earlier quoted context omitted.

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

Elevation is relative to sea level, not the ground.

This only holds true if you’re flying at or above the transition altitude. The transition altitude depends on where you’re flying: for example, in the USA and Canada it’s 18_000 feet MSL.

Re: WiFi without internet on a Southwest flight

#222

Earlier quoted context omitted.

Interesting how they chose to make more general `vehicleId` instead of `planeId` or `tailNumber` or something. I wonder if Delta's fleet includes other things that have matching APIs to this one. I also wonder how much of their internal system structure one could learn from the `flightId` if they knew about other systems. It doesn't look like much beyond a composite key of otherwise knowable data, but still interesti…

I doubt Delta made this. It’s an official the shelf product that can do ships, trains, planes, etc.

Valid point. It makes a lot of sense in that light instead.

Re: WiFi without internet on a Southwest flight

#223
post #214

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, eventual…

I used to do the same thing at hotels. Still often works. nmap -sn 192.168.0.1-255 To find everyone on the network, then start spoofing each of their MACs until you find one that works

Does that work if both of you are trying to send/receive packets at the same time?

Re: WiFi without internet on a Southwest flight

#225

Earlier quoted context omitted.

Good catch! I'm not very familiar with knots - what specifically makes the speeds here look like knots to you? edit: Updated the article. Thanks!

Airline planes never use mph but only knots.

Well, most airlines. I think both China and Russia already switched to SI units (so km/h), and supposedly ICAO recommends using km/h but there is exception for using knots and there is also no end date to stop using knots, so everyone just continues to use knots.

Re: WiFi without internet on a Southwest flight

#226

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…

It would be nice if you could send a POST request to open the door if you want some fresh air.

You probably can. I suspect airliner software is appallingly insecure.

Re: WiFi without internet on a Southwest flight

#227
post #18

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…

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…

Does that work on Android? I've never seen a non-authorized notification in a Chat or Mail app on a flight.

Re: WiFi without internet on a Southwest flight

#228

Earlier quoted context omitted.

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

Elevation is relative to sea level, not the ground.

The plane is measuring altitude, which is relative to a reference point, unlike elevation which is relative to sea level. And if the altitude is determined by pressure sensor, musn't it be relative to the ground directly below the plane, anyway?

(Although personally, I agree with the sibling comment that the variability is likely an artifact of the sensor resolution.)

Re: WiFi without internet on a Southwest flight

#229

Earlier quoted context omitted.

Interesting how they chose to make more general `vehicleId` instead of `planeId` or `tailNumber` or something. I wonder if Delta's fleet includes other things that have matching APIs to this one. I also wonder how much of their internal system structure one could learn from the `flightId` if they knew about other systems. It doesn't look like much beyond a composite key of otherwise knowable data, but still interesti…

I doubt Delta made this. It’s an official the shelf product that can do ships, trains, planes, etc.

But they also have airplane/flight specific identifiers like “flightNumber”, “flightId”, “noseId(?)” and “airSpeed”. Maybe vehicleId is part of a base class or primary key somewhere and that abstraction is leaking.

Re: WiFi without internet on a Southwest flight

#230
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?

Planes report pressure altitude via their transponders. 20-30 feet up and down is very normal for an autopilot.

GPS altitude is used for vertical guidance for certain types of GPS approaches (i.e. "LPV" approaches[1]) and requires the airplane's avionics to be equipped with a WAAS[2] receiver that provides accurate altitude information.

[1] https://en.wikipedia.org/wiki/Localizer_performance_with_ver...

[2] https://en.wikipedia.org/wiki/Wide_Area_Augmentation_System

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