Bad Signal

[controller]

Hy,

I have my new receiver and have some questions.

I saw a plan from NET2 radar detectetd. First there was a ? and the plane and has signal.

I had the plane on my PlanePlotter Software with a good signal, all data was O.K. Other planes were plottet in FR24 O.K. so I could see that my data will be delivered.

So my question is if an other station has a better signal does FR24 does not change the radar source
?

An other thing ist the flight route of the plane ends sometimes not directly at the plane, even if the plane was tracked continously.
Can someone explaine me how this works, even if you have discussed in the forum then please give me the link.

Ralph

[Admin]

If you click on an plane with (?), you can see that airplane info shows:

Ground speed: 0 knots
(0 km/h / 0 mph)
Track: 0°

Thats means that we have not received information about flight track and can not draw a plane, so we put a (?) on map.

[controller]

Hello Admin,

but :

>
I had the plane on my PlanePlotter Software with a good signal, all data was O.K. Other planes were plottet in FR24 O.K. so I could see that my data will be delivered.

Can there be a delay changing the source radar ?

Ralph

[Charky]

Hi,
as it looks to me somebody is playing around with the data or there is a serious problem with the input queue.
It is not the weather, nor the clouds or reflections who are creating phaenomena like this.

[Charky]

Hi, Controller,
I don't know if that helps, but I had a look onto the signals you are receiving here at FR24, but as it looks like, you are sitting behind the Taunus (being blocked by Feldberg, Platte and Hohe Wurzel). Therefore getting low flying traffic from EDDF seems to be not possible. You catch up flights from EDDF at a minimum of 8000 meters (very rarely at 3000m). Flights coming from the northwest flying to EDDF you catch at about 3000m or less.
I guess you are sitting near Niedernhausen or Idstein ?

[controller]

Hello Charky,

you are a good navigator, Niedernhausen is only 3 km far from me.

I know the problem you describe, but the origian question is that I could see good data on PP, delivering data to FR24 but FR24 used the bad data from net2 instead my better data for a special plane. Therefore the question what data will be used.

Ralph

[Charky]

Hi,
there must be a program running at the server (or nearby) which brings both sources together and depending on how the data is handeled it ends up like this. Perhaps a solution could be only to handel good messages, then sort them by time and let them go. No idea. Sometimes you can see 30 planes vanishing at the same time.
But perhaps somebody of the crew here can explain.
(I am born in Wiesbaden therefore I know this countryside)

[Anmer]

Hell
I know the problem you describe, but the origian question is that I could see good data on PP, delivering data to FR24 but FR24 used the bad data from net2

When you say "good data on PP" what was "good" about it when compared to Net2 data?

[scanhorse]

Hi
I was thinking that maybe NET2 would be the same as PP network ??

Ulf , scanhorse

[Mike]

ADS-B receivers are radio-receivers, any anyone who have listened to radio know that there could be interference. And often the interference is very short and very local. So two cars travelling on the same road listening to the same radio station can have different interference.
We receive data from 120 receivers. Every receiver is sending data once every 10 second, and the data is a snapshot of the current traffic situation just before upload. Every snapshot is containing thousands of 0 and 1 so it's very probably that almost every upload to server is containing some errors on some of the aircraft data. That can be missing speed, missing position, missing callsign, missing track, missing height for any aircraft in the upload.

And we are just showing what we get.

12:00:00 Radar A: Uploads Track: 120°
12:00:02 Radar B: Uploads Track: 121°
12:00:07 Radar C: Uploads Track: 122°
12:00:10 Radar A: Uploads Track: 122°
12:00:12 Radar B: Uploads Track: error
12:00:17 Radar C: Uploads Track: 121°

If you load the page 12:00:05 you will see Track: 121°
If you load the page 12:00:15 you will see a (?)

When we are handling 10-15 uploads per second containing thousands of aircrafts we have no possibility analyzing every piece of data, and making a guess if it's reasonable or what should be inserted instead. We don't neither know if it's a temporarily error, or permanent error, or airplane flying out of coverage. For you looking at one plane is easy to guess that it should turn right or left because it's landing on 27L or 11R, for the server handling millions of 0 and 1 every second the guess is not so easy.

[Mike]

Here is a snapshot of the database, you can see, there data missing everywhere.

[Charky]

Thank you Mike
if alt, lon,att is missing scratch it.
I know it is very difficult and time consuming.
But please please avoid to play with this data and then redisplay it (to show flight corridors).

[Mike]

I can just add that this problem
Ground speed: 0 knots (0 km/h / 0 mph)
Track: 0°
seems to be very common on Boeing 777-200 aircraft, if you zoom out to Europe and click on the (?), you will notice that many are B772.