Flight radar and missing aircraft

[Zippee]

Just a random question really to satisfy my curiosity.
Do all aircraft need to file a flight plana and their transponders etc pick up on sites like FR?
Reason I ask is I get quite a few light aircraft and also WW2 warbirds fly over where I live but despite the fact they're quite visible to me FR has nothing shown for miles around and even on a wider search no sign of the aircraft in question.
Yet it'll pick up the gliders from the local club.

Hopefully not a daft question, just interested in how it works

[r3g]

Zippee said:

Just a random question really to satisfy my curiosity.
Do all aircraft need to file a flight plana and their transponders etc pick up on sites like FR?
Reason I ask is I get quite a few light aircraft and also WW2 warbirds fly over where I live but despite the fact they're quite visible to me FR has nothing shown for miles around and even on a wider search no sign of the aircraft in question.
Yet it'll pick up the gliders from the local club.

Hopefully not a daft question, just interested in how it works

FR24 told all its feeders to disable MLAT about a year ago or have their feed forcibly disconnected. The reason for this is still unknown. Pretty much all GA, helis, low-level and ancient stuff without ADSB 1090ES transponders needs MLAT to be tracked. No MLAT = you don't see planes on the map. FR24 is finished.

Gliders and a lot of ULACs have their own network. They transmit on 978 MHz rather than ICAO on 1090 MHz. The glidernet (as it's known) is extremely well covered throughout Europe. There are thousands and thousands of feed sites, mainly provided by the gliding clubs themselves as it's obviously within their interests to stop them from crashing into each other.

Edited by r3g on Friday 10th February 16:22

[Zippee]

Thank you - so in essence FR have shot themselves in the foot and are not receiving the key data they'd otherwise need? Why would they do that?

[dudleybloke]

Which sites track them all?

[r3g]

Zippee said:

Thank you - so in essence FR have shot themselves in the foot and are not receiving the key data they'd otherwise need? Why would they do that?

I've heard various stories but there's never been an announement from FR24 about the reasons for their decision. There was some rumour about feeds from old SBS receivers were sending out corrupt and/or inaccurate packet data and so it was easier to just block MLAT altogether. The feed location co-ords and world server clock time sync accuracy of the data is paramount for plotting MLAT traffic because if one of the feeders is not in sync then you end up with jagged tracks plotting across the map. It's also very CPU intensive, which may be a factor too.

I'm not sure what the current status is with MLAT feeds as the US Navy P8s rarely ping, yet they still show up on the map showing MLAT as the source. But certainly for low level GA that just does circuit bashing at your local grass strip - yeah you're not going to be seeing any of that on FR24 anymore unless they have one of the more modern transponders that ping mode-S with extended squitter (1090ES).

[48k]

Zippee said:

Do all aircraft need to file a flight plana and their transponders etc pick up on sites like FR?

Just so you know, you're asking two separate questions here. Filing a flight plan is nothing to do with transponder settings.

[Simpo Two]

Zippee said:

Thank you - so in essence FR have shot themselves in the foot and are not receiving the key data they'd otherwise need? Why would they do that?

Over-interpretation of some law?