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

wsj.com

41–50 of 197 posts

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

#42

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.

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

#43
post #28

Earlier quoted context omitted.

Radar has been jammed in the past by accident , since home routers now operate on the same band. See https://arstechnica.com/information-technology/2015/09/fcc-a... . 5G coming in doesn't improve matters. GPS is actually reserved, so there's going to be a lot less accidental interference.

>GPS is actually reserved, so there's going to be a lot less accidental interference. that's only a plus if you're not expecting malicious interference . how much harder is radar to spoof compared to GPS?

Considering it's unauthenticated, and you can buy a broadcaster in the proper band for $50 at Best Buy and load it with DD-WRT? I'm going with "as easy if not easier than GPS", considering GPS spoofing requires equipment you likely don't already have (a can of Pringles and your current router).

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

#44
I worked for a firm, which studied satellite navigation and implementation for air traffic control, guidance, safety, and ILS. I don't think that will ever happen. There are huge gaping issues with GPS, both WAAS and GBAS. It's very unreliable, especially in bad weather. The old-school RF tower and ILS, which used Carrier frequency pairings by the runway, are way more reliable and propagate bad weather while guiding the plane into a runway. There's also been ongoing issues with truckers, with GPS jammers, which drive by airports impacting the quality of signal for planes coming into runway. Even the GPS signal itself has latency and lag, which prevents the plane from making quick adjustments for avoiding traffic and ILS guidance.

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

#45
post #41

What's the point in posting an article which has a paywall? Does anyone have a link which points to an open version of the article?

Apparently WSJ is okay with you reading things if you request the content with the correct incantations. There are a bunch of paywall bypass plugins for Firefox that invoke the magic words. Here's one:

https://addons.mozilla.org/en-CA/firefox/addon/read-ft-wsj/

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

#46
post #9

If there's anyone in the air control technology industry here, I'm curious what parts of this change get you really excited, and which parts get you really nervous?

The cost. This affects general aviation as older planes will require avionics upgrades. Otherwise I’m excited for the sheer amount of data that will be made available to the public. Now you will be able to track all FAA registered planes

Have you seen any official discussion of the data being made available?

I feel like, for example, I'd be worried if fine-detail GPS data was being published live for example, or live enough to predict where the plane is "right" now...

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

#47

There was a talk at DEFCON about this in 2012 [1]. The main issue is a radar system gets its information from ground-based measurements, while a GPS system gets its information from air-based measurements that are later transmitted to the ground station. This means that those reports can be spoofed, or lied about, or absent entirely. https://www.youtube.com/watch?v=CXv1j3GbgLk

The validity of location data can be verified by cross checking where the plane claims it is, and where the signal is detected to be, via MLAT:

* https://en.wikipedia.org/wiki/Multilateration

* https://www.radartutorial.eu/02.basics/rp52.en.html

* http://www.multilateration.com/surveillance/multilateration....

This can further be cross checking with space-based systems like Nav Canada's:

* https://en.wikipedia.org/wiki/Aireon

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

#48

I worked for a firm, which studied satellite navigation and implementation for air traffic control, guidance, safety, and ILS. I don't think that will ever happen. There are huge gaping issues with GPS, both WAAS and GBAS. It's very unreliable, especially in bad weather. The old-school RF tower and ILS, which used Carrier frequency pairings by the runway, are way more reliable and propagate bad weather while guiding…

This change allows every pilot to have essentially a 'radar view' of their surroundings, cheaply. A receiver and an iPad app give them a picture much like the aircraft control tower would have.

Lots of issues I'm sure. It'll be interesting to see how this sorts out.

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

#49

I worked for a firm, which studied satellite navigation and implementation for air traffic control, guidance, safety, and ILS. I don't think that will ever happen. There are huge gaping issues with GPS, both WAAS and GBAS. It's very unreliable, especially in bad weather. The old-school RF tower and ILS, which used Carrier frequency pairings by the runway, are way more reliable and propagate bad weather while guiding…

Why do truckers have GPS jammers?

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

#50

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 where you thought you were. We did not fly over open water at night.

Later we got a primitive GPS, no maps just waypoints and lat/lng. That thing was so much easier to use it was night and day. Just dial in a 3 letter code for your airfield, and you get range,bearing,eta.

GPS is a huge improvement to safety and convince, but if it goes out a night or in bad weather there are gonna be some problems.

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