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WiFi without internet on a Southwest flight

jamesbvaughan.com

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Re: WiFi without internet on a Southwest flight

#591

Post by phkahler »

dramm wrote: 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…

>> Autopilots are very good and they are servoing to the pressure altitude.

It would have been cool to use a phone to record a GPS track with altitude and compare them. Pressure != GPS. Also wonder if there would be distinct jumps in the difference if they reset the pressure based altimeter to a different AWOS.

Not sure how it works in big planes, but in little ones you need to set your altimeter based on the local weather. The weather stations measure barometric pressure at their elevation and "correct it to sea level" you get this corrected reading over the radio and set it in your altimeter so your pressure-based altitude reading is corrected for local weather variations. Just going out flying for an hour the altimeter setting when returning to the same place might be off by a few millibar.

Re: WiFi without internet on a Southwest flight

#592

Post by danjc »

blcknight wrote: post #171
eddieroger wrote: post #169

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.

"Official the shelf" - that your new iOS 17 update helping you out? ;)

Re: WiFi without internet on a Southwest flight

#593

Post by kristopolous »

cromka wrote: post #540
kkyr wrote: post #443

Earlier quoted context omitted.

How do you determine who the top talkers are?

By setting the WiFi card into monitor mode, and using by e.g. Kismet for data collection.

I did it with tshark but yes this is a pretty easy problem to solve.

I think I even made a script in lua to do it automatically

Re: WiFi without internet on a Southwest flight

#594

Post by plg »

barrkel wrote: post #557
sprokolopolis wrote: post #375

Earlier quoted context omitted.

I used to do this on airplanes and in hotels. I had more success in hotels, because there was less chance the other person was using it at the time and less chance of getting kicked off. There was another little hack that I used as a little kid. Remember when airlines would sell or rent special headphones to watch inflight movies? The port was just two holes beside each other and the plug was two tubes. Before a flig…

How long ago was this? 20 years ago, all I saw were dual mono bayonet jacks you'd need an adapter for to plug in normal headphones, but straws would get you nowhere. I was curious so I searched: https://simpleflying.com/inflight-entertainment-headphones-e... - pneumatic headphones from the 1960s were used on Delta as late as 2003, but electronic headsets debuted on 767 in 1982. Apparently the dual mono jacks are to d…

As a kid in the 80s we used to fly YVR-HNL every winter … always pneumatic earphones.

Re: WiFi without internet on a Southwest flight

#595

Post by gfo »

phkahler wrote: post #591
dramm wrote: 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…

>> Autopilots are very good and they are servoing to the pressure altitude. It would have been cool to use a phone to record a GPS track with altitude and compare them. Pressure != GPS. Also wonder if there would be distinct jumps in the difference if they reset the pressure based altimeter to a different AWOS. Not sure how it works in big planes, but in little ones you need to set your altimeter based on the local w…

You use standard pressure (29.92 inHg) above transition altitude, which, in the United States, is 18,000 feet. Pilots wouldn't be changing the altimeter after climbing past this point, and would start using local values once descending through it again.

Of course, your initial point is still correct: there could be slight variations if using those local settings and getting different values, but you'd only see that below transition altitude.

Re: WiFi without internet on a Southwest flight

#596

Post by tim333 »

phkahler wrote: post #591
dramm wrote: 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…

>> Autopilots are very good and they are servoing to the pressure altitude. It would have been cool to use a phone to record a GPS track with altitude and compare them. Pressure != GPS. Also wonder if there would be distinct jumps in the difference if they reset the pressure based altimeter to a different AWOS. Not sure how it works in big planes, but in little ones you need to set your altimeter based on the local w…

At high altitude you do this stuff "When you set your altimeter to 29.92, you're flying at standard pressure altitude."

The idea is all the planes use the same setting so the one at FL35 doesn't hit the one at FL36. But those are not exactly 35000 and 36000 feet above sea level.

Re: WiFi without internet on a Southwest flight

#598

Post by brookst »

cutemonster wrote: post #551
daveevad wrote: post #441

Earlier quoted context omitted.

> The other person will get frustrated and disconnect and reconnect a few times, and finally give up and read a book... That makes me really reconsider my past struggles with this form of Internet access.

Time to consider instead: walk through the plane, look angrily at the other passengers, one at a time, asking: "Do you use 192.168.x.y?". That can solve the problem

Or convince the flight attendants to including “MAC address spoofing” in the spiel about destroying or tampering with lavatory smoke detectors.

Re: WiFi without internet on a Southwest flight

#599

Post by Zigurd »

MostlyStable wrote: post #341
josu wrote: post #333

Earlier quoted context omitted.

Why not just use the hotspot on your phone?

I believe that you can't both simultaneously provide wifi hotspot and use wifi internet (at least, I couldn't on a phone several years ago last time I tried it). I think you can only do that if the network the phone is using is accessed via the cellular modem.

Depends on the phone OS and wifi chipset Some Pixel phones can do it last I checked, which was about a year ago. It's a fragile dependency. For example, a Samsung with the same wifi chip didn't work.

Re: WiFi without internet on a Southwest flight

#600

Post by nelgaard »

pantalaimon wrote: post #280
KMnO4 wrote: post #214

Earlier quoted context omitted.

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

I’ve never been at a hotel that charged for WiFi - is that a US thing?

It used to be common everywhere.

From my point of view, free WiFi became normal when it became less important because of affordable mobile internet.

From the point of view of the hotels it was about recovering their missing income after customers got mobile phones and stopped paying half a dollar per minute for using the hotel phones. There was a period when both mobile roaming and hotel WiFi was expensive, so I often went out from my hotel room and bough a local SIM-card to get internet access.

What annoys me most, is that only when I finally could get a laptop that would work a full transatlantic flight on one charge, then suddenly airplanes all got power outlets.

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