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Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

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Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#141

Post by echelon »

TkTech wrote: post #88
qrbLPHiKpiux wrote: post #79

Earlier quoted context omitted.

But the risks and consequences are catastrophic. The Feds will put you away forever for even attempting it.

And most major airports have systems like RFEye or AIRPORT-SHIELD. You would be _immediately_ pinpointed with a remarkable level of accuracy from 3-6 sensors. Especially near major metro areas, unintentional interference is a daily issue. These systems immediately triangulate sources of interference in a wide band. Or you have simpler systems like UMS100 that just do alerting and you send out an engineer with a wand…

Imagine an unlicensed drone emitting GPS radio signals. Just a small amount of sophistication and an attacker can do an incredible amount of harm.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#142

Post by jandrese »

amluto wrote: post #133
tyingq wrote: post #63

Earlier quoted context omitted.

Beating DOT legalities, hiding things like side trips to casinos/mistresses/bars from the boss, general dislike for big brother, etc.

It should be straightforward to have GPS jammer detectors along the road. Throw in a giant federally enforced fine and people will stop using them.

In fact these do exist. I saw a demo a few years back from a company that tracked bogus GPS signals and how they could watch jammers drive around the streets of London all day long.

These guys were doing it because they were tasked with keeping LTE towers synchronized and they did it with GPS time so they were building in resilience to their time sources by measuring the signal level and rejecting anything that came in too strong. Spotting jammers was a side benefit.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#143

Post by jandrese »

opwieurposiu wrote: post #50
griffinkelly wrote: post #7

I very recently had my ADSB fail while flying in a piper arrow. I think its probably good to have redundant systems in place, its a core to aviation to do that with instruments. Also, the military jams GPS rather frequently for exercises: https://www.thedrive.com/the-war-zone/17987/usaf-is-jamming-...

Ah the piper arrow. Fond memories of many trips around florida and caribbean in that plane as a kid. It was my job to "help" with the navigation, using a paper chart and VOR/NDB steam gauge instruments. Dad was able to teach 10yo me how to do this stuff, but it was easy to confuse from/to or think you are tuned to station x when actually you are on Y, etc. Particularly night VFR was hard to be sure you were exactly w…

If it goes out you're back to the old methods, but of course you're all rusty on those old methods because you don't normally have to use them.

I've had kids ask me what we did before we had GPS and Google Maps and I tell them that we got lost or turned around a lot more often.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#144

Post by jcrawfordor »

jessaustin wrote: post #125
jcrawfordor wrote: post #89

Earlier quoted context omitted.

In the US, ATC radar and military radar are one and the same - the FAA and the Air Force share the Joint Surveillance System (JSS). So, while the JSS has plenty of limitations (including plenty of areas with no coverage even in the mainland US), it's designed to meet the military objectives of being able to locate even non-cooperating aircraft. The JSS is a descendant of the SAGE system developed during the Cold War…

Is there any other entity that operates these sorts of radomes? On a regular commute of mine, there is one owned by the federal government that has no sign out front [0], but it's not listed on the JSS page [1]. [0] https://goo.gl/maps/KHTP7vruKvGyqQu66 [1] https://en.wikipedia.org/wiki/Joint_Surveillance_System

It took a bit of digging... this is an FAA radar, but not JSS. It's a secondary radar reporting to the Kansas City ARTCC, code ZQJN. Essentially, it transmits an 'interrogate' message in response to which aircraft transponders transmit information on the aircraft. This is the system that ADS-B is more or less a direct upgrade from.

I'm not sure exactly what equipment is installed there, I found an older report listing an ASR-8 at that location but that system is obsolete and inconsistent with a newer list showing it as a secondary (SECRA) site only.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#145

Post by Patrick_Devine »

danaliv wrote: post #129
Patrick_Devine wrote: post #109

Earlier quoted context omitted.

The problem with _requiring_ authentication is that it can create a safety issue when communications break down. As a pilot it's not a bad idea to carry a spare handheld radio, or even use a cel phone, when you lose communications. I was flying once with a buddy of mine who was Pilot-In-Command and we lost (or thought we had lost) our radio on an IFR flight back into the Bay Area. What had happened was the Push-to-Ta…

Seven six, on the fritz! (Squawk 7600.) There’s an established, cut—and-dry procedure for when an IFR aircraft goes NORDO. Even without that handheld, you would’ve been fine. Every airplane between you and your destination, on the other hand, would find themselves being rerouted.

I didn't mean to imply that we thought we were in any kind of imminent danger. There were three pilots (including myself) in the plane, all whom had trained in a highly congested area.

My point was that having the handheld radio allowed us to trouble shoot the situation. Without the radio there would have been a lot higher workload and less of a margin for safety.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#146

Post by redis_mlc »

jrockway wrote: post #67

A lot of comments seem to be about spoofing. Remember that there are multiple humans in the loop -- experienced pilots and experienced air traffic controllers -- and multiple levels of redundancy. Pilots have access to barometric altitude, radar altitude, traditional VHF navaids, TCAS-issued resolution advisories (based on directional antennas, not GPS)... in addition to GPS. Air traffic controllers have primary rada…

> Air traffic controllers have primary radar and secondary radar in addition to ADS-B information.

No they don't.

Most secondary (surveillance) radar in the US has been shut down already.

The FAA has been busy shutting down basically anything that requires maintenance, and LORAN is gone too.

I believe the whole point of ADS-B out was to shut down basically the rest.

Source: commercially-rated pilot.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#147

Post by tropo »

TkTech wrote: post #88
qrbLPHiKpiux wrote: post #79

Earlier quoted context omitted.

But the risks and consequences are catastrophic. The Feds will put you away forever for even attempting it.

And most major airports have systems like RFEye or AIRPORT-SHIELD. You would be _immediately_ pinpointed with a remarkable level of accuracy from 3-6 sensors. Especially near major metro areas, unintentional interference is a daily issue. These systems immediately triangulate sources of interference in a wide band. Or you have simpler systems like UMS100 that just do alerting and you send out an engineer with a wand…

With an omnidirectional antenna, sure. With a high-gain antenna, no. The attacker could entirely avoid the RFEye or AIRPORT-SHIELD. The attacker could pick a specific aircraft to pester, with no other aircraft able to listen.

Add some fancy voice synthesis, and it gets interesting. The attacker could clone the voice and style of the air traffic controller. The attacker could provide enough power to quiet out any other transmissions. To keep the air traffic controller incompletely aware, the attacker could provide interference (just to the tower) whenever the victim aircraft begins to transmit.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#148

Post by tropo »

jandrese wrote: post #142
amluto wrote: post #133

Earlier quoted context omitted.

It should be straightforward to have GPS jammer detectors along the road. Throw in a giant federally enforced fine and people will stop using them.

In fact these do exist. I saw a demo a few years back from a company that tracked bogus GPS signals and how they could watch jammers drive around the streets of London all day long. These guys were doing it because they were tasked with keeping LTE towers synchronized and they did it with GPS time so they were building in resilience to their time sources by measuring the signal level and rejecting anything that came…

The GPS antenna on the LTE tower should only be picking up signals from the sky. Transmitters on trucks would need to reflect off of aircraft in order to cause trouble, which would greatly weaken the signal.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#149

Post by wrycoder »

redis_mlc wrote: post #146
jrockway wrote: post #67

A lot of comments seem to be about spoofing. Remember that there are multiple humans in the loop -- experienced pilots and experienced air traffic controllers -- and multiple levels of redundancy. Pilots have access to barometric altitude, radar altitude, traditional VHF navaids, TCAS-issued resolution advisories (based on directional antennas, not GPS)... in addition to GPS. Air traffic controllers have primary rada…

> Air traffic controllers have primary radar and secondary radar in addition to ADS-B information. No they don't. Most secondary (surveillance) radar in the US has been shut down already. The FAA has been busy shutting down basically anything that requires maintenance, and LORAN is gone too. I believe the whole point of ADS-B out was to shut down basically the rest. Source: commercially-rated pilot.

If you shut it all down and something catastrophic somehow goes wrong with GPS, it will be very difficult to get the thousands of planes in the air back onto runways.

Re: Air-Traffic Control Is in the Midst of a Major Change from Radar to GPS

#150

Post by tjohns »

redis_mlc wrote: post #146
jrockway wrote: post #67

A lot of comments seem to be about spoofing. Remember that there are multiple humans in the loop -- experienced pilots and experienced air traffic controllers -- and multiple levels of redundancy. Pilots have access to barometric altitude, radar altitude, traditional VHF navaids, TCAS-issued resolution advisories (based on directional antennas, not GPS)... in addition to GPS. Air traffic controllers have primary rada…

> Air traffic controllers have primary radar and secondary radar in addition to ADS-B information. No they don't. Most secondary (surveillance) radar in the US has been shut down already. The FAA has been busy shutting down basically anything that requires maintenance, and LORAN is gone too. I believe the whole point of ADS-B out was to shut down basically the rest. Source: commercially-rated pilot.

Do you have any citations from the FAA for that?

Given that then ADS-B mandate was just a couple weeks ago, it seems logistically odd that secondary radar would already be turned off.

More generally, my understanding was that the FAA was keeping primary+secondary radar around to augment ADS-B via sensor fusion. I know the "reply" light on my plane's radar transponder still lights up regularly, so at least out here on the west coast the secondary radar is still active. :)

I've also heard there's a longer-term plan to consolidate ATC radar into the NOAA weather radar stations, once they upgrade weather radar to phased-arrays at some unknown point in the future. The marginal cost to keep secondary radar running in that environment is basically zero.

That said, they have certainly been turning down many of the redundant VOR stations as part of MON, and they just turned HIWAS off last week.

I don't think anyone really misses LORAN, though. ;)

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