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

wsj.com

121–130 of 197 posts

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

#121
post #73

Earlier quoted context omitted.

It will probably be easier to spot them, since very few planes will show up on radar and not on the GPS system. It might be enough to go take a visual immediately once this is fully online.

I thought the way that they historically avoided detection was to quite literally fly below the radar. Wouldn't that still work with this new system, they just wont show up anywhere?

That is one way, but sometimes they do show up / try to mimic other traffic / etc. That part of things would be reduced.

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

#122
post #76

Earlier quoted context omitted.

> buying an aviation radio off the shelf and just chatting on the frequency or issuing fake clearances if you want to be a mass murderer Incidentally, I am happily surprised that that never seems to happen. One could so easily create so much chaos at an airport... There is no authentication whatsoever.

It happens sometimes [1] It actually happened near me once when a local crazy guy got mad that planes were flying near his house (he bought a house right across the street from the municipal airport) so he found an airband radio and started yelling at them every time they came too close for his liking. [1] https://www.youtube.com/watch?v=ZvA_-linhg8

Wiarton is pretty far from Toronto. But I dunno how many receiving/sending antennae they have for « Toronto Centre ».

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

#123

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-...

Not just for exercises. There are places in America where it's permanently jammed, most often near military bases.

Really? Where? I overview Edwards AFB last week (with clearance as Joshua Approach gave me a shortcut across the restricted areas,) I flew close to Vandenberg last month, not an overfly, but just on the edge of the airspace, I also flew near Fort Huachucha, AZ which is an Army Intel post. I flew right near the Yuma Proving Ground on another trip. Even flew right on the edge of the series of restricted areas containing Area 51 — not a single place was GPS jammed. Even Camp Peary and a few other extremely sensitive sites aren’t permanently jammed.

Even jamming near Nellis and Area 51 is done by NOTAM and not perpetual.

Maybe there is some permanent jamming somewhere but pilots would know about it as GPS availability knowledge is safety critical.

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

#124

Earlier quoted context omitted.

Could they? A moving target? Say the soundproofed back of some van.

I personally would volunteer to be on one of the teams in another van with directional antennas to triangulate your transmissions and shut down you ASAP. The fact that no one has ever truly tried that sort of poisoning of radio calls is more due to the tower and aircraft having a very well defined set of calls, so that the likelihood of false transmissions being able to cause havoc is minimized already. I agree with…

My question was of theoretical nature, i'm not up to mischief of that sort. Though i'm often thinking about the vulnerabilities of our technological society, and the (false) assumptions we have about that. Compare it with lock picking. Most are easily bumped, or not even bothering with that, the door kicked down, some window used instead, and so on. Now, when someone kicks your door down, that's getting noticed, sooner or later.

But what about cheap SBCs dropped somewhere with a battery and some custom periphery working as a relay? Of course the SUVs could find that. After the fact.

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

#125
post #74

Regarding posts about spoofing and maintaining radar, it was my understanding that the radar sets that most ATCs used was not actually powerful enough to get direct returns from commercial aircraft, and relied on amplifying transponders to be able to see them. Supposedly only militaries operate radars powerful enough to see aircraft directly. Can anyone who knows more confirm or deny? If that's true, I guess we're al…

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

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

#126
post #104

Earlier quoted context omitted.

Well that's interesting. How does that tie in to the story's reported change though? I suppose ATCs might be willing to rely solely on aircraft-reported location and speed, but I kind of doubt the USAF would. If they share the same systems, I suppose no equipment would actually change or be decommissioned.

I think that the article's implication that radar is being 'replaced' refers only to the daily work of controllers, not to the technical system. Both the FAA and the Air Force have strong motives to keep the primary radar system, and it would take many years to decommission it even if they wanted to - but near-100% availability of ADS-B does mean that controllers will use it as their primary source of data, instead o…

Nobody is even suggesting eliminating radar. ADS-B is primarily for aircraft identification, not terminal area location information. A side effect is that it helps with airborne traffic information for airplanes without radar or TCAS.

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

#127
post #83

Earlier quoted context omitted.

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

While true, you'd think state sponsored terrorism wouldn't care about sacrificing a few people.

actually, I'd think state sponsored terrorism would have the resources to get away with it.

Just send the voice data through a raspberry pi to a remote location and carry out the attack from there. You could send voice data through a TOR-like protocol or something to keep you anonymous, if that's important. You could maybe rig some explosives to go off if the FBI/FCC/FAA gain access to the attack point, to prevent them from recovering evidence.

Lot's of police/fire radio systems are similarly without authentication, so you could amplify the mayhem by doing the same thing to those frequencies.

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

#128

Earlier quoted context omitted.

It happens sometimes [1] It actually happened near me once when a local crazy guy got mad that planes were flying near his house (he bought a house right across the street from the municipal airport) so he found an airband radio and started yelling at them every time they came too close for his liking. [1] https://www.youtube.com/watch?v=ZvA_-linhg8

Wiarton is pretty far from Toronto. But I dunno how many receiving/sending antennae they have for « Toronto Centre ».

Toronto Centre is in the top level of the ATC hierarchy and is a geographic area rather than specific to the city of Toronto. Airband AM only has a range of 50-200mi in flight so they have outlying stations, usually colocated with VOR stations IIRC.

He probably got lucky and had a station within 5-10 miles of his bathtub...

https://en.wikipedia.org/wiki/Toronto_Area_Control_Centre

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

#129
post #76

Earlier quoted context omitted.

> buying an aviation radio off the shelf and just chatting on the frequency or issuing fake clearances if you want to be a mass murderer Incidentally, I am happily surprised that that never seems to happen. One could so easily create so much chaos at an airport... There is no authentication whatsoever.

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.

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

#130

Radar isn’t going away. This article talks as if ADS-B is replacing radar, which it’s not. It’s enhancing radar where radar coverage exists and providing coverage on traffic where radar coverage currently does not exist (usually lower altitudes away from major airports and over the ocean).

Indeed. Not everyone even has to have ADS-B Out. You only need it if you’re going into or over Class C or B airspace, in the Class B veils, Class E above 10,000 except below 2500 AGL, and in Class E over the Gulf of Mexico. That leaves huge swathes of airspace—dare I say most airspace in the US—where ADS-B isn’t required. You could fly across the entire country without hitting an ADS-B requirement. And the only way for ATC to see non-ADS-B aircraft is radar.
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