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I don't know how aircraft systems work. Can a directional antenna spoofing ILS [2] cause the crash of an airliner using ILS to land in bad visibility conditions

I don't know how aircraft systems work. Can a directional antenna spoofing ILS [2] cause the crash of an airliner using ILS to land in bad visibility conditions? Does the plane trust the ILS signal? What if you combine that with a GPS jammer or GPS spoofer? Or do we consider that military technology, like MANPADs, and so out of scope? But some airlines consider MANPADs in scope, and use flares or laser systems to defend against them [1]. 1 - https://en.wikipedia.org/wiki/Flight_Guard https://en.wikipedia.org/wiki/Flight_Guard 2 - https://en.wikipedia.org/wiki/Instrument_landing_system https://en.wikipedia.org/wiki/Instrument_landing_system

colechristensen 7y ago
When you know answers to questions like this it becomes an ethical question whether to share your knowledge.
- temac 7y ago
  It depends. We now have this little thing called the Internet, and you can quickly learn a ton of things on it. Even if you just learn a few points and without all the details, that's still better than nothing and at least a starting point for further study, if needed. And it depends on the direction of the answers too. For example I think most autoland still require some amount of visibility a few seconds before touchdown, and the pilots are supposed to go around if they do not have it. Plus, I believe planes also use a radio altimeter while landing. But I don't believe they use GPS for the final approach. So you might put a plane in a difficult position with that kind of attack, but not necessarily making it crash. And there are probably more easy ways to do more damage.
throw20102010 7y ago
Possibly, but the pilots would have to screw up as well. You typically tune in the ILS when you're expecting to pick up the approach. It's not like you set the ILS frequency hours before landing and just follow the first signal that pops up. So if you do follow a malicious signal, it's going to be few miles away from the airport at the furthest. However, ILS is becoming less used because it requires maintenance of ground systems. GPS approaches could also be spoofed, but would be a more sophisticated attack. But with GPS navigation you aren't tuning radio frequencies in your nav equipment so there's probably more chances to fool a pilot (you could drag them much further away from the airport if you started spoofing GPS further out). However, ALL instrument approaches have minimum visual altitudes, and the lowest I'm aware of is 200 ft above the ground. If you can't see the airport by the time you get down to the minimum altitude you execute a missed approach procedure- basically you climb and navigate to another waypoint to restart the approach or to hold. Additionally, all aircraft must have barometric altimeters as required equipment- no amount of radio spoofing can fool them. So in an ideal world an attack would go like this: the pilot follows the malicious approach, notices that they are at the minimum altitude, looks for the airport but doesn't see it (or sees it a few miles away), then executes a missed approach- no crash. There aren't too many tight approaches that could make you crash by being off by a mile. To get around this you would need to spoof either the pitot-static (pressure sensing) system, or the pilot's altimeter setting. You could only spoof the pitot-static system by sabatoge on the ground, and you can only realistically spoof the altimeter setting by pretending to be ATC on the radio- at which point the real ATC would correct whatever you said and get real suspicious. Of course, given that instrument landings are the highest workload portion of a flight, pilots get distracted. Even if they would normally catch on to the fact that they aren't on the correct approach, you might cause a few crashes by pilots that aren't on top of their game. Edit to add one more thing: Your plane is tracked by airborne surveillance as well, and if you claim to be at a waypoint and that doesn't match what ATC has on their scope they will warn you. So you'd have to also spoof a surveillance signal at the correct location while blocking the real planes signal to keep ATC from noticing.
- tgsovlerkhgsel 7y ago
  > However, ALL instrument approaches have minimum visual altitudes, and the lowest I'm aware of is 200 ft above the ground. https://en.wikipedia.org/wiki/Instrument_landing_system#ILS_categories https://en.wikipedia.org/wiki/Instrument_landing_system#ILS_... claims "<50 ft" decision height for CAT IIIb.
  - throw20102010 7y ago
    Then I suppose that with really bad visibility someone could probably fake an ILS and cause the plane to crash without the pilots having the chance to recover. After looking around, it seems that several large airports,.and even a few medium size airports in the US have Cat III approaches: https://sites.google.com/site/ilsapproaches/Home/cat3 https://sites.google.com/site/ilsapproaches/Home/cat3 I never even considered the possibility of a CAT IIIc where you can land in zero visibility, probably because I'll never fly an airplane with suitable equipment. I've never briefed flying a CAT III approach, and wouldn't even consider landing at those airports in the light planes that I fly. In my local area around KDEN the general consensus is that while it's technically legal to land a light plane at KDEN you would probably have to declare an emergency to get clearance from ATC, and even then they'd strongly encourage you to land somewhere nearby (like KFTG) if possible.

colechristensen 7y ago

When you know answers to questions like this it becomes an ethical question whether to share your knowledge.

temac 7y ago
It depends. We now have this little thing called the Internet, and you can quickly learn a ton of things on it. Even if you just learn a few points and without all the details, that's still better than nothing and at least a starting point for further study, if needed. And it depends on the direction of the answers too. For example I think most autoland still require some amount of visibility a few seconds before touchdown, and the pilots are supposed to go around if they do not have it. Plus, I believe planes also use a radio altimeter while landing. But I don't believe they use GPS for the final approach. So you might put a plane in a difficult position with that kind of attack, but not necessarily making it crash. And there are probably more easy ways to do more damage.

throw20102010 7y ago

Possibly, but the pilots would have to screw up as well. You typically tune in the ILS when you're expecting to pick up the approach. It's not like you set the ILS frequency hours before landing and just follow the first signal that pops up. So if you do follow a malicious signal, it's going to be few miles away from the airport at the furthest. However, ILS is becoming less used because it requires maintenance of ground systems. GPS approaches could also be spoofed, but would be a more sophisticated attack. But with GPS navigation you aren't tuning radio frequencies in your nav equipment so there's probably more chances to fool a pilot (you could drag them much further away from the airport if you started spoofing GPS further out). However, ALL instrument approaches have minimum visual altitudes, and the lowest I'm aware of is 200 ft above the ground. If you can't see the airport by the time you get down to the minimum altitude you execute a missed approach procedure- basically you climb and navigate to another waypoint to restart the approach or to hold. Additionally, all aircraft must have barometric altimeters as required equipment- no amount of radio spoofing can fool them. So in an ideal world an attack would go like this: the pilot follows the malicious approach, notices that they are at the minimum altitude, looks for the airport but doesn't see it (or sees it a few miles away), then executes a missed approach- no crash. There aren't too many tight approaches that could make you crash by being off by a mile. To get around this you would need to spoof either the pitot-static (pressure sensing) system, or the pilot's altimeter setting. You could only spoof the pitot-static system by sabatoge on the ground, and you can only realistically spoof the altimeter setting by pretending to be ATC on the radio- at which point the real ATC would correct whatever you said and get real suspicious. Of course, given that instrument landings are the highest workload portion of a flight, pilots get distracted. Even if they would normally catch on to the fact that they aren't on the correct approach, you might cause a few crashes by pilots that aren't on top of their game. Edit to add one more thing: Your plane is tracked by airborne surveillance as well, and if you claim to be at a waypoint and that doesn't match what ATC has on their scope they will warn you. So you'd have to also spoof a surveillance signal at the correct location while blocking the real planes signal to keep ATC from noticing.

tgsovlerkhgsel 7y ago
> However, ALL instrument approaches have minimum visual altitudes, and the lowest I'm aware of is 200 ft above the ground. https://en.wikipedia.org/wiki/Instrument_landing_system#ILS_categories https://en.wikipedia.org/wiki/Instrument_landing_system#ILS_... claims "<50 ft" decision height for CAT IIIb.
- throw20102010 7y ago
  Then I suppose that with really bad visibility someone could probably fake an ILS and cause the plane to crash without the pilots having the chance to recover. After looking around, it seems that several large airports,.and even a few medium size airports in the US have Cat III approaches: https://sites.google.com/site/ilsapproaches/Home/cat3 https://sites.google.com/site/ilsapproaches/Home/cat3 I never even considered the possibility of a CAT IIIc where you can land in zero visibility, probably because I'll never fly an airplane with suitable equipment. I've never briefed flying a CAT III approach, and wouldn't even consider landing at those airports in the light planes that I fly. In my local area around KDEN the general consensus is that while it's technically legal to land a light plane at KDEN you would probably have to declare an emergency to get clearance from ATC, and even then they'd strongly encourage you to land somewhere nearby (like KFTG) if possible.