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Flightradar24's new GPS jamming map

flightradar24.com

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Re: Flightradar24's new GPS jamming map

#71

Post by kube-system »

imoverclocked wrote: post #23
tdudhhu wrote: post #13

Is interference the same as jamming? I am absolutely no expert in this but I can imagine that even natural occurrences can interfere with the GPS.

There are things that will naturally interfere with GPS and they are fairly well known. The FAA provides an expected outage map [1] (a forecast, if you will) for pilots that may need that info. Jamming is an act by humans to intentionally disrupt the GPS signal. [1] https://sapt.faa.gov/outages.php?outageType=129001450&outage...

And I think the above commenter's point is that ADS-B data does not indicate intentionality.

Re: Flightradar24's new GPS jamming map

#72

Post by lxgr »

kube-system wrote: post #68
lxgr wrote: post #57

Earlier quoted context omitted.

How does an airplane "point their GPS receiver at the ground" (for an extended period of time since a combined GNSS/INS positioning solution, which is what all airliners use at this point as far as I know, will need an extended signal loss to report decreased accuracy)?

Probably something like this https://youtu.be/Ynvoriv09Ks?t=105

Ah, is this Ryanair's plan to divest from their all-Boeing fleet? :)

It should be pretty simple for Flightradar24 to exclude non-commercial aircraft from the data through, which would solve that problem.

There's also tons of data available in the ADS-B signal that should help distinguish between aircraft-motion-induced outages and actual jamming: https://mode-s.org/decode/content/ads-b/7-uncertainty.html

Re: Flightradar24's new GPS jamming map

#73

Post by croemer »

If line of sight to the jamming antenna is required to be jammed, why do aircraft not have a downwards shield so that they only receive GPS signal from the sky (satellites) and not from jammers (coming from the bottom hemisphere)? Or is the jamming signal so many orders of magnitudes stronger than the satellites that there's always going to be some gain no matter how good the shield is?

Ok it exists, but shielding is (only) about 20dB looking downwards, which may not be enough: https://safran-navigation-timing.com/product/8230aj-gps-gnss...

Re: Flightradar24's new GPS jamming map

#74

Post by traceroute66 »

lxgr wrote: post #58
traceroute66 wrote: post #48

Earlier quoted context omitted.

> I don't live in that country though Exactly. You don't live there. Not many people live in the Australian desert. Conclusion: No data or very limited data

"No data" cells are grey on that map, but western Australia has a couple of red ("high interference") cells.

> but western Australia has a couple of red ("high interference") cells.

Erm mate, have you tried looking at different days ? Those cells you find so suspicious in Australia are not there on other days !

Seriously, given the largely community-based nature of FR24 data I would not expect too much in term of accuracy.

Re: Flightradar24's new GPS jamming map

#75

Post by jcrawfordor »

barryrandall wrote: post #61
ukd1 wrote: post #52

Earlier quoted context omitted.

really? unless they're jamming it, how would that happen?

Rapidly execute a series of maneuvers (flips, rolls) that cause the radios to lose signal.

So I'm a little skeptical on that front because military aircraft are still not that often broadcasting ADSB even during routine flights, at least in my (also close to the border) region. In theory the Air Force was supposed to have completed ADSB installation on their fleet last year but they blew the deadline pretty bad on even installing transponders, and of course they still reserve the right to disable them during military operations.

Maybe with the data we can figure out what portion of military flights are included?

For the helicopter training flights that I notice most often, it's still rare to see one that broadcasts ADSB, probably The paper linked elsewhere (https://web.stanford.edu/group/scpnt/gpslab/pubs/papers/Liu_...) mentioned issues with military training flights resulting in spurious low-NIC cases but unfortunately doesn't quantify it. With the way the AF rollout has gone it probably depends on the specific installation, command, and aircraft type.

In the border region specifically we would tend to expect the majority of non-military flights to be civilian CBP aircraft that aren't performing unusual maneuvers. CBP has a somewhat complicated and limited authority to disable ADS-B that I don't know the contours of, I'm not sure how often they do so on their larger (non-sUAS) aircraft. Involvement of the Air National Guard in the Texas area might complicate the analysis though.

Re: Flightradar24's new GPS jamming map

#77

Post by icegreentea2 »

Does anyone know if the how the ADS-B uncertainty measurements interact with GPS spoofing? Often when you look at these maps you see a donut around Kaliningrad - could it be that there's wide area jamming, and then localized spoofing more directly around Kaliningrad?

Re: Flightradar24's new GPS jamming map

#78

Post by rootusrootus »

hammock wrote: post #14
wyldfire wrote: post #6

I wonder why there's some jamming near a small section of the Texas/Mexico border?

That is Eagle Pass, TX. The infamous, massive border crossing area where suspected criminal border crossers are corraled under the bridge, where Elon visited, etc. The jamming is done to make crossing the border without going through the checkpoint more difficult

That's north of Eagle Pass. Laughlin AFB is on the southwestern edge of those two red cells. Eagle Pass is like 50-60 miles south.

Re: Flightradar24's new GPS jamming map

#80

Post by javier_e06 »

tivert wrote: post #9

So how should I interpret this? The map lacks geopolitical boundaries, so it's hard to interpret. There looks like a big hole of no data over Ukraine, where I'd most expect GPS jamming, but I suppose there are no civilian flights either. Maybe they could setup an GPS observation station on the ground at a surveyed point to get data there. There's a big red blob over Turkey, is that maybe the southern edge of the reac…

I see 2 red cells on the US/Mexico border right about Texas/Coahuila region. Navigating that dessert region without GPS or with GPS for that matter can be deadly.
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