A very weird one on ADSB Exchange

[Mystify]

OK so I'm new on here but been using the above tracking site for some time just to input to my lifelong aviation interests. I joined yesterday in order to see if someone could shed some light on this. I will be staying as I love this site.

A couple of weeks ago I was checking out military activity over the UK. i admit it was the end of a hard day and I should have been in bed. Not feeling at the top of my game. It was just coming up to 2300. My attention was drawn to a concentration of stuff over Chepstow, on the South Wales/England border. When I zoomed in (I mean right in) I found myself looking at the following all at ground level on what seemed to be a small park in the southern suberbs of the town:
1. F35 Lightning - UK
2. Chinook - UK
3. Osprey - US
Circling the town at 20k ft and radius of approx 10nm was a U2 and a RAF Hawk was going up and down the severn estauary just to the east. I'm completely serious and def not joking. I did a double take and assumed it was some weird glitch with the website. I came out of it completely and went back in - yep it was all still there. You would think the whole town would have been woken up but I've checked local news outputs since then and nothing at all.

After about 20 mins they all started to leave together heading NE but after only 20 NM they vanished from the screen.
Give me a clue somebody.

[POL]

Someone messing about and injecting fake traffic through their ADS-B receiver. There was also a B-52 and U-2 at Fairford that weren't really there.

[Nighthawke]

Reported elsewhere as a glitch, unsurprisingly.

[Skymaster]

Someone messing about and injecting fake traffic through their ADS-B receiver. There was also a B-52 and U-2 at Fairford that weren't really there.

Is that even possible?

I noticed the B-52 plotting on the ground at Fairford, too. It was one of the four that were at Fairford almost a year earlier.
Screenshot...
https://cdn.discordapp.com/attachments/ ... nknown.png

The B-52 was actually at Tinker, and departed shortly afterwards.
https://globe.adsbexchange.com/?icao=ae ... rackLabels

On reporting this to the developer, I was informed "It's not the system, it's a real signal....".

The only thing I could think of at the time, was that a transponder that had been removed from the B-52 was being tested at Fairford. However, this seems highly unlikely, and too much of a coincidence.

As there seem to have been a number of spurious plots in the same area, I now wonder if someone's Pi had become corrupt and was sending duff data. Also seems unlikely, as I believe that kind of data gets filtered out.

So... a glitch of some sort, it would appear.

If anyone has details/screenshots of other spurious plots during that time frame, please post.

[Pete Da Bear]

F35 over Chepstow according to ADSB 00.15 local time 10 Aug.

[Malcolm]

Someone messing about and injecting fake traffic through their ADS-B receiver. There was also a B-52 and U-2 at Fairford that weren't really there.

Is that even possible?

It's dead easy to do. Most of the tracking sites rely on uploads from normal "civilian" sharers rather than official radar feeds. If one of those sharers goes to the dark side there is nothing to stop them uploading spoof ADSB messages. The tracking sites could stop/reduce it by requiring uploads from multiple sharers before showing a given target, but that would reduce coverage in places with a low sharer density and at low altitude.

I routinely take analogue recordings of ADSB messages in order to try and improve the decoding in dump1090. If I replayed one of those recordings into the upload software I could (for instance) make Grim99, AF1 and Sam46 reappear in the skies over the UK at any time of the day (or night).

[EAGLE]

Just an update, at around 0010L the BUFF, U2 and F-35 were showing again, in the same locations on ADSBx

[EAGLE]

0250, the F-35 was back, again on multiple trackers.

[John flightpath]

0100hrs and the F35 is showing agaIn over Chepstow. ZM145

John

[Skymaster]

Were they on 360radar?

[rh226]

30/08/2021

01.33BST Voyager ZZ336 popped up over Chepstow showing the callsign "BRIAN001" which quickly changed to "BRIAN".