271–280 of 299 posts
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ADS-B is only commercial flights? I thought many kinds of flights are broadcasting. Does Flightradar24 only track commercial flights?
I doubt there’s any private flights over Ukraine too. Military planes generally don’t advertise their location in combat zones
About three or four civilian aircrafts were able to leave Ukraine during the war and every departure was a major military operation to undertake.
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Airplanes don't need GPS to fly. Jamming GPS won't cause any crashes.
GPS jamming is already thought to have caused one drone accident, with fatality: http://lemondronor.com/blog/index.php/2013/3/gps-loss-kicked... And there have been several close calls already, with passenger jets: https://spectrum.ieee.org/faa-files-reveal-a-surprising-thre... Planes don't need radar, transponders, or even radio to fly, but they're all very important for safety.
Here in Europe VORs are also very rare now. Makes sense because they're hugely expensive to operate and when used only for backup it's not a very good investment.
Currently I am working for a new wireless PHY technique that is more secure and robust against jamming, and also the first that able to propagate with limited non line of sight (NLoS). Hopefully soon we can overcome this anti human GPS/GNSS jamming shenanigans.
For an excellent example for anti jamming secure wireless network for GPS (not my work) please check this thesis by Cara Yang Kataria [1]. She is currently working at the infamous MIT Lincoln Laboratory.
[1] Antenna-driven methods for increased wireless network security:
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They do that! Unfortunately, they don't always know when they're being spoofed, so oops, your inertial reference system has just been infected by the spoofed location and now both nav systems are hosed. https://ops.group/blog/gps-spoof-attacks-irs/ https://aerospace.honeywell.com/us/en/about-us/blogs/spoofin...
Though shouldn't be that hard to know if you are being spoofed. You probably have a decent idea of how much the IRS drifts and any large deviations from that or unexpected jumps in GPS should be noted and possibly, maybe manually, rolled-back so that the IRS only considers data before that point. I understand that current civilian aircraft wasn't designed with that in mind though.
Practically that was what happened all the time before GPS. You would fly for a few hours over the ocean with no ground based reference, having a reasonable but not perfect INS location. Then get close to the coast where a DME/DME fix was done which updated the INS position as a big jump of up to a few miles.
Filtering GPS updates that are too far "off" the INS state would be an almost opposite design to the original assumptions that DME and GNSS are highly accurate.
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"Do aircraft systems really only use GPS" I know older long-range planes from the 70s and 80s had excellent inertial navigation systems. Not quite as good as GPS, but good enough to know the location of the plane within a few nautical miles. The main problem is that inertial navigation systems drifted over time and required constant recalibration from the crew whenever they had a fix from real navigation beacons and…
Based on discussions of some accidents, pilots often ignore inertial navigation systems at which they rarely look today, and sometimes forget to set the known good location before flights (which does not depend on GPS, as airports don't move).
Modern aircraft will also set the known position based on the runway you're taking off from. And when airborne they'll pick up a DME/DME fix and update the location. So while it's procedure to set the known starting location at the gate, there are also other sources.
I've been working on mapping GPS jamming using ADS-B data for a couple years, and I'll try to address questions and points brought up here based on what I know. Relevant previous posts on HN: 2022: https://news.ycombinator.com/item?id=32245346 2023: https://news.ycombinator.com/item?id=37868106 (From my comment on that 2023 post: "Why haven't FlightRadar24, FlightAware, or any of the other flight trackers done this?"…
> but my understanding is that most aircraft are still using GPS. GNSS, GPS plus other constellations depends on the receiver. Even drones or consumer ones support that these days, some bigger drones even support L5 bands.
So your 100 dollar drone very likely has a receiver with more features than a 100 million dollar airliner. And that drone is probably made recently, but airliners fly for 30 years.
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According to Wikipedia [0]: > The Kurdish language was banned in a large portion of Kurdistan for some time. After the 1980 Turkish coup d'état until 1991 the use of the Kurdish language was illegal in Turkey.[52] > Before August 2002, the Turkish government placed severe restrictions on the use of Kurdish, prohibiting the language in education and broadcast media.[55][56] In March 2006, Turkey allowed private televi…
In the 1980s, Iraqi Kurds were fleeing to Turkey for freedom and safety. The Prime Minister was of Kurdish origin. You could hear people speak Kurdish freely anywhere between the west and east end of the country. There were no "anti-Kurdish" laws and policies. The pro-American coup d'état in 1980 came with a law to control non-Turkish publications, but it was never put into action.
Here's a 1999 Human Rights Watch report – "RESTRICTIONS ON THE USE OF THE KURDISH LANGUAGE" – https://www.hrw.org/reports/1999/turkey/turkey993-08.htm
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Well, if you identify them then you might have to do something about it. But it's not clear there's much to be done. Sometimes it's easier to deny or just not mention that someone is acting in a hostile way. The example I often think of is Iran firing missiles at U.S. warships during Operation Praying Mantis, and then, as Wikipedia puts it: "The Pentagon and the Reagan Administration later denied that any Silkworm mi…
Biden did kind of the same. A few years ago he promised russia "devastating consequences if Navalny dies in prison". So Navalny did die in prison. What did Biden do? Right.
NATO in a certain way is based on that as well. If it fails a single test regarding article 5 after someone challenges it, it becomes instantly worthless.
The danger as I see it currently is that the West is tired of war and it’s an opportunity for Putin to challenge NATO. Attack a small village in a Baltic state. Are Americans and Germans and the British going to risk their lives for a small village in a Baltic country? I hope they would, but I realistically don’t see it. And that one non-response would make NATO worth less than the paper the agreement was printed on.
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"Do aircraft systems really only use GPS" I know older long-range planes from the 70s and 80s had excellent inertial navigation systems. Not quite as good as GPS, but good enough to know the location of the plane within a few nautical miles. The main problem is that inertial navigation systems drifted over time and required constant recalibration from the crew whenever they had a fix from real navigation beacons and…
They do that! Unfortunately, they don't always know when they're being spoofed, so oops, your inertial reference system has just been infected by the spoofed location and now both nav systems are hosed. https://ops.group/blog/gps-spoof-attacks-irs/ https://aerospace.honeywell.com/us/en/about-us/blogs/spoofin...