Commercial Flights Are Experiencing ‘Unthinkable’ GPS Attacks and Nobody Knows What to Do::New “spoofing” attacks resulting in total navigation failure have been occurring above the Middle East for months, which is “highly significant” for airline safety.
Fucking serves them right, the aviation industry have been buying GPS devices for decades that bleed outside and don’t explicitly filter down to their spectrum. There was a satellite internet startup in the US that went through the whole process, bought its spectrum and was ready to launch, then the aviation industry complained and had them shut down because their devices were all shit and “it would be too difficult to change everyone’s equipment”.
Do you have something I can read about this? It’s a little vague, so hard for me to search, and it sounds like something I would be interested in. Thanks
Pretty sure this is the story, rings true to my memory of the company name starting with “L”: https://arstechnica.com/tech-policy/2011/04/lightsquared-broadband-a-threat-to-gps/
Although this article doesn’t cover how the GPS systems used cheap filtering circuits that didn’t adequately filter out adjacent frequencies. This was done purely to save money, because there wasn’t anything using the adjacent frequencies. As a result, LightSquared went bankrupt in 2012.
Thanks I’ll give it a read.
Edited my last comment, I don’t think that article goes into much detail. It only really covers the objections by GPS device manufacturers against LightSquared, not the technical aspect ie poor filtering by cheap GPS devices.
This article covers LightSquared’s claims of poor filtering by GPS devices: https://www.networkworld.com/article/696602/wireless-lightsquared-says-gps-makers-ignored-filtering-rules.html
This article also covers some of it: https://www.cnet.com/tech/mobile/lightsquared-blew-it-and-heres-why/
TL;DR GPS devices cut corners, however because they were established and so endemic across the industry, there was no practical way to fix them all and LightSquared was sent down the toilet.
deleted by creator
Yet another reason to avoid the middle east
I’ve got an idea, how bout stop using the same technology from 20 years ago?
Huh what do you propose then, go back to the 1960s and ensure they are only using VOR and DME ground equipment. There isn’t a check sum to check on GPS/GNSS it just a bunch of satellites broadcasting what they think is the correct time. If you jam those and replace them with signals close enough but wrong values you can trick the math that’s used inside the GPS/GNSS receiver that computes the the position (and velocity), and it looks like this signal can be introduced slow enough to trick the receiver in real-world applications. One trick to protect yourself is to ensure the signals you receive are from the direction you expect but we aren’t going to attach directional antennas on every face of a civilian aircraft, to ensure the strongest signal is from the top of the plane and not the bottom. Essentially civil navigation equipment isn’t supposed to be messed with and if it is authorities are supposed to go over and arrest and fine the idiots doing things over the radio they shouldnt. When the bad guy is a government well yea I guess that plan doesn’t work and governing bodies such as ICAO should impose penalties like no commerical aircraft from companies from those countries are not allowed elsewhere.
That’s one way to do it.
Or avionics companies could sell modern equipment that uses multiple constellations (GPS, GLONASS, Galileo), is capable of acquiring more satellites at a time than a 20 year old system, and has basic jamming protection like ignoring spurious signals. You know: like consumer devices have been doing for years.
Then the commercial operators could install them in their aircraft.
First Glonass is a mess, missing quite a few operational satellites Galileo is just ramping up.
Interms of what is broadcast they still work on the same principle satellites broadcast time receiver does something like a linear least squares fit to estimate position, and time.
Mixing all the sources and doing a linear least squares like fit means the bad guy has to spoof more signals, and this system will be more robust but it is susceptible to the same attack just ramped up a bit
Just equip the airliners with modified AGM-88 HARM missiles to deal with the jammers.
Yea then they just start shooting down everything randomly,
And really want needs to be modified on the missiles? Sounds more like an airliner issue to me…
Sounds like they should remove the explosive part before putting into an airliner but maybe that’s just me
Something that sounds like a production flaw to me is how the IRS gets corrupted. Sadly the article did not go too much into detail, but gyroscopes and accelerometers should not be affected by GPS data. Sure, if they do not sync up with current data, error propagation becomes a problem - especially on long flights. But i reckon gradually depreciating data is better than maliciously wrong data.
The article mentioned, that large plains have 2 GPS receivers. The spooving seems less traditional (sending wrong data with more power), but more sending a lot of incomplete data to confuse the receiver. This should introduce a desynchronization of the two receivers present, and alert the internal systems. Since it is detected, that something went wrong with the GPS, the 3 IRS can calculate the position from recorded data. This is a fallback and accuracy will depreciate. But if the pilot is aware it could still be valuable information. Additionally it is more scalable than air traffic control having to navigate affected planes.
What about GLONASS, Galilleo, or BDS? Are they all being equally jammed? Why wouldn’t they sync with all of them and use a consensus to determine accuracy? Like having multiple ntp servers.
The latest generations of gnss receivers have spoofing and jamming mitigation and detection features included with the chip, and multi-band rx technology to sync to more constellations simultaneously and do exactly what you’re talking about. Before then, the spoofing/jamming detection would likely need a software implementation after the receiver. There are different types of spoofing/jamming, all of which are detected and mitigated in different ways.
I don’t know the commercial aircraft industry standards for updating technology, but I wouldn’t be surprised if most commercial aircraft don’t have what you’re talking about.
That just means you can’t use autoland in low visibility conditions. Modern IRUs (inertial reference unit) are highly accurate laser gyros that can use GPS for correction, but will throw out the data if it doesn’t make sense. Navigation won’t be affected much, and autoland (if used) will still rely on VHF guidance.
Ignore my ignorance. Are you saying the aircrafts track where they are going by calculating their position from gyroscope data? And this is more precise than GPS?
That’s like using the accelaration sensors in your phone to navigate. Or sailing with compass and nautical maps.
Possible. Tech isn’t even that novel. But still impressive.
Yes. Most of commercial navigation systems rely on the IRUs as a primary source of position data, and they’ll usually have 3 of them. VHF is used by the crew to confirm that the aircraft is on track by referencing VOR stations, though these are slowly being phased out due to GPS.
That being said, a single traditional IRU can have up to 2km of drift over a 2 hr flight (at which point it’s removed from service and replaced). When used in combination with two other IRUs, the error is dramatically reduced. Traditional IRUs are gyroscopically mechanical in nature and do not talk to GPS.
Now, that being said, the new standard is called an ADIRU (ADvanced IRU), which ties in with GPS and features laser gyros. They’re extremely accurate and have essentially zero drift, plus multiple redundant components within each unit.
If anyone is really curious about how INS works https://en.m.wikipedia.org/wiki/Inertial_navigation_system
Also this Air Force training audio REALLY clears the subject up: https://youtu.be/VUrMuc-ULmM
The Missile Knows Where It Is
Transcription for the audio is as follows:
"The missile knows where it is at all times. It knows this because it knows where it isn’t. By subtracting where it is from where it isn’t, or where it isn’t from where it is (whichever is greater), it obtains a difference, or deviation. The guidance subsystem uses deviations to generate corrective commands to drive the missile from a position where it is to a position where it isn’t, and arriving at a position where it wasn’t, it now is. Consequently, the position where it is, is now the position that it wasn’t, and it follows that the position that it was, is now the position that it isn’t.
In the event that the position that it is in is not the position that it wasn’t, the system has acquired a variation, the variation being the difference between where the missile is, and where it wasn’t. If variation is considered to be a significant factor, it too may be corrected by the GEA. However, the missile must also know where it was.
The missile guidance computer scenario works as follows. Because a variation has modified some of the information the missile has obtained, it is not sure just where it is. However, it is sure where it isn’t, within reason, and it knows where it was. It now subtracts where it should be from where it wasn’t, or vice-versa, and by differentiating this from the algebraic sum of where it shouldn’t be, and where it was, it is able to obtain the deviation and its variation, which is called error."
Here is an alternative Piped link(s):
https://piped.video/VUrMuc-ULmM
Piped is a privacy-respecting open-source alternative frontend to YouTube.
I’m open-source; check me out at GitHub.
The missile knows where it is by knowing where it is not.
But the article mentioned that “the spoofing corrupts the Inertial Reference System”. How?
If it’s a smaller plane (such as a CRJ / ERJ) with only one IRU, it will not be able to determine if GPS is valid or not, so the drift correction gets spoiled.
Large commercial aircraft are using 3 IRUs, with newer aircraft using ADIRUs. If GPS does not agree with the three IRUs, the GPS data is thrown out. If the GPS is within tolerance, correction is applied. You could build up very small errors over a long distance, but you should still be pretty close to the airfield when you get there.
Well the article says it caused at least one plane to almost fly into Iran’s restricted airspace…
How do IRUs work do to give you location?
We need a backup for GPS. LORAN should never have been shut down.
There are 3 of them. Galileo, Glonass and Beidou
Will time to fire up the floppy drives for updates!
I generally don’t believe in an isolationist American policy except for Israel. They always drag us into stupid shit like this.
Do none of the systems, GPS, glonass etc. use encryption or authentication of any form?
Yes Galileo supports encryption. But as far as I know it’s not in use. Has been trialled only. But I know all Airbus aircraft only support GPS satellites and nothing else (yet). I assume Boeing, being American would be the same then.
As far as solutions go, an aircraft can navigate fine without GPS. It can update its position from ground navigation aids and if they are not available it can still Dead Reckon very well. The navigation error very slowly grows until it’s out of the black spot and can use GPS or navigation aid to increase its accuracy. But this navigation error on the time frame of say an hour is a matter of kilometers at most, not dozens.
