This is jamming and not GPS spoofing. Wouldn't the navigation system 'fail' and that pilot switch over to flying by heading? I would think the civilian craft would have to be robust in the presence of spoofing (military testing). ATC would declare a certain area as GPS off, a NOTAM or something.
> "Aircraft are greatly affected by the GPS jamming and it's not taken seriously by management," reads one report. "We've been told we can't ask to stop jamming, and to just put everyone on headings."
This is the military practicing, but I would hope that civilian airline transport operations are also robust to GNSS unavailability or denial. Even private pilots in little Cessnas are taught to navigate using radio-navigation (NDB beacons, VORs, etc.) in the event that GPS is not available. You should absolutely be able to turn your GPS off and get to your destination.
The fact that radio-navigation aids are being phased out in favor of GNSS, turning it into a single point of failure, is pretty concerning.
Are there NOTAMs regarding GPS jamming operations? It's not a fix, but maybe it would allow pilots - specially ones without sophisticated avionics like those founds in airliners(who don't rely on GPS in flight) - to prepare and/or avoid the issue.
All military navigation systems are inertial, not GPS. They only accept GPS corrections within the error bars of the inertial system. As a practical matter this means that you can only make a drone deviate from its intended course by a few meters assuming you did a perfect job of spoofing the GPS.
GPS spoofing/jamming only works for systems that use GPS navigation systems; military weapons and systems have never used GPS navigation. Inertial navigation systems are spoof-proof.
Perhaps I just don't understand how this works all that well, but shouldn't it be easy to defeat GPS spoofing when you're 30,000+ feet in the air? Presumably the spoofed GPS signals are all coming from the ground, or close to it. I would think it would work to use a semi-directional antenna that is on top of the aircraft, pointing upward. Even an antenna that has a 180-degree field of view should reject fake GPS signals from the ground, no?
Only thing I can think of that would invalidate this is if the fake GPS signals bounce off the atmosphere above the planes and come back down. What else am I missing here?
Commercial traffic flying at 30-40 thousand feet is not flying VFR typically. And of course spotting landmarks through cloud cover or at night is not a thing. But you are right that spoofing would largely just be annoying. Commercial traffic is usually in contact with a controller and monitored on radar. So, any course deviations would result in controllers asking what they are doing and be followed by them simply vectoring them back on course with compass headings.
However, GPS has replaced a lot of the NDB and VOR radios that pilots used to rely on. Also a lot of airport approaches are now GPS rather than ILS/VOR. It's pretty critical to modern aviation.
GPS, or rather GNSS (which includes GPS and other systems), spoofing is a concern; but so far mainly in conflict areas. Most airlines would route around those.
Resilience against spoofing is actually a big topic from a strategic point of view. Also, spoofing is a big part of counter measures against drones in e.g. Ukraine. So there is a bit of an arms race going there.
The point with GNSS is that most phones can utilize multiple satellite positioning systems at the same time at this point. Which is of course something that navigation systems in planes could also do. And of course many pilots actually use ipads in the cockpit, which they could use as a backup in case of an electrical failure in the plane.
If it is indeed GPS spoofing it must be happening to commercial vessels right? Doesn't the US military use a different, more accurate/secure version of GPS? It seems more likely the less secure AIS protocol is somehow being manipulated.
Consumer grade GPS actually won't work at 30,000+ feet at speeds the plane would be flying. This is to prevent someone from using the GPS system to steer a ballistic missile.
To an extent, this sounds terrifying. The first thing that jumped to my mind is that GPS be jammed or spoofed. In fact, the U.S. military in its shift away from COIN to great power competition in possibly highly contested environments is training to have less reliance on GPS: https://www.zerohedge.com/news/2018-01-26/usaf-begins-massiv...
Radar can be jammed too, but I would guess the EM signature powerful enough to track. I don't know if GPS jammers would have that issue.
On a positive note, I think this would pave the way towards integrating commercial drone infrastructure into our airways a lot better!
Not really, whatever you are jamming you can just make sure it doesn't make it 10 km up in the air where most of the planes are (especially given the GPS patch antenna pointing up from the plane), and I don't believe they need GPS signal on takeoff/landing, they use older tech for that.
This article focuses on US military GPS tests in US and airline safety mainly, but does mention similar tests happening in Europe and China. Regarding these latter it does not name who is doing the jamming.
> Anyone who can buy a GPS jammer could disrupt one of the busiest airports in the world.
Fortunately, that one is not quite the case – the aviation industry is incredibly safety-conscious and does not allow relying on GPS exclusively.
For both en-route navigation and landing, every plane will have at least one fallback system available (usually ground-based radionavigation aides such as VORs or DMEs or inertial navigation systems, which is also what was used for navigation during ocean crossings before there was GPS), and in fact, these other systems are seeing more use than you might assume: https://www.thedrive.com/the-war-zone/17987/usaf-is-jamming-...
> Presumably the spoofed GPS signals are all coming from the ground, or close to it.
I think that's a good presumption when operating in, say, Iraq or Afghanistan. Maybe less so when operating near Russia (which has its own GNSS system)?
> I would think it would work to use a semi-directional antenna that is on top of the aircraft, pointing upward. Even an antenna that has a 180-degree field of view should reject fake GPS signals from the ground, no?
GPS receivers already do this to reject ground reflections that could give false position readings (and the GPS signal is circularly-polarized so it can reject odd-ordered reflections off building and the ground). However, any kind of steerable (electronically or otherwise) directional GPS antenna is considered an ITAR no-no.
The other problem is that GPS signals are incredibly weak (actually below the thermal noise floor), and rely on processing gain from the CDMA chipping to raise the SNR to something useful. So even an antenna with very very good rejection from the lower hemisphere will easily pass a jamming signal from the ground which is both many times closer and probably of higher power.
> Only thing I can think of that would invalidate this is if the fake GPS signals bounce off the atmosphere above the planes and come back down. What else am I missing here?
Any country with a space program could transmit the jamming signal from above.
This article is really glossing over the fact that non-military jamming now occurs all the time, courtesy of truckers and criminals. Actual GPS jamming is only done rarely on special military ranges with significant separation from civilian traffic, or very rare wide-area trials (days when I would not have flown anywhere near the area in the NOTAM).
One thing is true: GA and Amati pilots rely too heavily in GPS. If they can't fly with DR+VOR in VFR then maybe they shouldn't fly through an area with GPS interference...
I looked far and wide, and there's nothing. However, inertial guidance is subject to drift, so if you spoof the GPS slow enough you can bypass inertial guidance as a protection.
The most interesting part of the RQ-170 story however is how they managed to track it accurately enough for GPS spoofing to begin with - you need a track accurate to a few dozen meters to do that, and it's supposed to be super stealthy even beyond the stealthiest fighter jets making that impossible.
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