Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Flightradar24 – how it works

habr.com

Post reply on HN
Print view View original

91–100 of 160 posts

Re: Flightradar24 – how it works

#91

Post by amingilani »

Perfect timing. I'm just in the process of building my own shortwave listening station in Lahore, Pakistan — which is definitely a low coverage area on both services. I was using a RTL-SDR + Pi and a homebrew antenna to cover the 2m band, so I guess I could run this in parallel. I was looking at volunteer run air quality monitoring services just this morning!

Just filled their forms. Slightly concerned about running a blackbox on my network so I'll have to do some isolation, but this'll be a fun contribution.

Re: Flightradar24 – how it works

#92

Post by Rebelgecko »

bicubic wrote: post #78
Rebelgecko wrote: post #44

Earlier quoted context omitted.

There's also https://opensky-network.org/ Their API is actually a bit more open than adsbexchange's

How is the data coverage compared to flightradar?

Last time I looked closely it was similar in North America and Europe. Asia, Africa, and over the oceans had some pretty big gaps.

There's also no delay on the data, although I think Flightradar and Flightaware dropped the 5 minute delay they used to have. Flightradar censors a lot of corporate jets and military/law enforcement aircraft but I don't think Opensky does. In fact one of either Opensky or adsbexchange even has a special flag in their REST API for "interesting" aircraft

Re: Flightradar24 – how it works

#93

Post by benoblak »

kaybe wrote: post #66
dewey wrote: post #28

Earlier quoted context omitted.

https://www.openseamap.org

Great! They don't seem to have historic ship positions though.. hm.

It seems like none of the AIS providers store historic ship positions, you probably have to do it yourself if you want that information

Re: Flightradar24 – how it works

#94

Post by cpncrunch »

alkonaut wrote: post #83

I’m assuming there is more to it than just the radio data? In FR you can see planes everywhere, including thousands of miles off shore. My guess is that FR24 just looks up the flight path from the flight number, and then once an airplane goes “off the radar” it just assumes it goes the shortest/great circle path towards its destination airport - at which point it will again be in a “known” spot? If this is how it’s d…

Yes, it looks like it does just estimate the great circle route. The lines are all dashed for the planes over the ocean, starting a few hundred miles offshore.

This may change soon -- at least for the North Atlantic -- now that Aireon is using satellites to pick up ADS-B data. It's just a question of whether or not this info gets included in the FAA's ASDI feed.

Re: Flightradar24 – how it works

#95

Post by tomfanning »

pard68 wrote: post #65
trishmapow2 wrote: post #30

Rtl-sdrs are great, probably one of the best accidental discoveries I've seen. So many things being sent out from 0-1.5GHz that you can sniff. One that I see often are the unencrypted pagers broadcasting patient details, hotel security information etc. Then you've also got amateur radio, air traffic control, GSM, key fobs, weather stations, satellites, all within the reach of anyone with $15 to spare.

I want[ed] to get one but the options are overwhelming. I dislike buying not-the-best product. I also dislike eBay, which seems to be one of the main methods of purchasing a setup (have been burned too many times by sellers).

Allow me to point you to SDRplay who have a line of USB receivers that are far more capable (more sensitive, less overwhelmed by strong signals, wider capture bandwidth, wider frequency range) than any of the RTL dongles, which only cover shortwave (https://www.sdrplay.com/

Re: Flightradar24 – how it works

#96

Post by rootusrootus »

Rebelgecko wrote: post #92
bicubic wrote: post #78

Earlier quoted context omitted.

How is the data coverage compared to flightradar?

Last time I looked closely it was similar in North America and Europe. Asia, Africa, and over the oceans had some pretty big gaps. There's also no delay on the data, although I think Flightradar and Flightaware dropped the 5 minute delay they used to have. Flightradar censors a lot of corporate jets and military/law enforcement aircraft but I don't think Opensky does. In fact one of either Opensky or adsbexchange eve…

The delay was a rule from the FAA for radar data provided by them, ADS-B plots have always been real-time. I am guessing (from the lack of orange icons anymore) that the ADS-B coverage is good enough now that FR24 is not using FAA feeds any more.

Re: Flightradar24 – how it works

#97

Post by graedus »

Rebelgecko wrote: post #92
bicubic wrote: post #78

Earlier quoted context omitted.

How is the data coverage compared to flightradar?

Last time I looked closely it was similar in North America and Europe. Asia, Africa, and over the oceans had some pretty big gaps. There's also no delay on the data, although I think Flightradar and Flightaware dropped the 5 minute delay they used to have. Flightradar censors a lot of corporate jets and military/law enforcement aircraft but I don't think Opensky does. In fact one of either Opensky or adsbexchange eve…

> I think Flightradar and Flightaware dropped the 5 minute delay they used to have

I was using Flightradar yesterday and visually tracking planes, seems like about a 10 second delay.

Re: Flightradar24 – how it works

#98

Post by Zhenya »

Rebelgecko wrote: post #92
bicubic wrote: post #78

Earlier quoted context omitted.

How is the data coverage compared to flightradar?

Last time I looked closely it was similar in North America and Europe. Asia, Africa, and over the oceans had some pretty big gaps. There's also no delay on the data, although I think Flightradar and Flightaware dropped the 5 minute delay they used to have. Flightradar censors a lot of corporate jets and military/law enforcement aircraft but I don't think Opensky does. In fact one of either Opensky or adsbexchange eve…

Using their UI, I can't seem to find the "interesting aircraft" tag. Here's what I see:

  * No data
  * No ADS-B Emitter Category Information
  * Light ( 300000 lbs)
  * High Performance (> 5g acceleration and 400 kts)
  * Rotorcraft
  * Glider / sailplane
  * Lighter-than-air
  * Parachutist / Skydiver
  * Ultralight / hang-glider / paraglider
  * Reserved
  * Unmanned Aerial Vehicle
  * Space / Trans-atmospheric vehicle
  * Surface Vehicle – Emergency Vehicle
  * Surface Vehicle – Service Vehicle
  * Point Obstacle (includes tethered balloons)
  * Cluster Obstacle
  * Line Obstacle

Re: Flightradar24 – how it works

#99

Post by Rebelgecko »

Zhenya wrote: post #98
Rebelgecko wrote: post #92

Earlier quoted context omitted.

Last time I looked closely it was similar in North America and Europe. Asia, Africa, and over the oceans had some pretty big gaps. There's also no delay on the data, although I think Flightradar and Flightaware dropped the 5 minute delay they used to have. Flightradar censors a lot of corporate jets and military/law enforcement aircraft but I don't think Opensky does. In fact one of either Opensky or adsbexchange eve…

Using their UI, I can't seem to find the "interesting aircraft" tag. Here's what I see: * No data * No ADS-B Emitter Category Information * Light ( 300000 lbs) * High Performance (> 5g acceleration and 400 kts) * Rotorcraft * Glider / sailplane * Lighter-than-air * Parachutist / Skydiver * Ultralight / hang-glider / paraglider * Reserved * Unmanned Aerial Vehicle * Space / Trans-atmospheric vehicle * Surface Vehicle…

Yeah that was actually with adsbexchange (https://www.adsbexchange.com/currently-airborne-interesting-...).

Re: Flightradar24 – how it works

#100

Post by bnchdrff »

sorenjan wrote: post #37
dewey wrote: post #25

Earlier quoted context omitted.

I thought it would be cool to have some kind of gateway service that collects the data and then sends if off to adsbexchange, flightradar and others but apparently it's not so easy. Someone else already asked this question before: https://www.reddit.com/r/ADSB/comments/ar3qrw/feed_to_a_sing...

Do you mean collect data from multiple receivers and send it off to various services from one computer? That messes with MLAT [0] calculations and shouldn't be done. If you want to send data to multiple services from one receiver all you need is to install the feeder for each service. Most uses dump1090 [1], but Flightradar24 uses their own. Dump1090 sends data in different formats to various local ports by default,…

If you aren't trying to send MLAT data to more than one server, it isn't an issue. You can do MLAT to, say, adsbexchange, and non-MLAT to flightradar24.
Post reply on HN