[HN Gopher] Air-Traffic Control Is in the Midst of a Major Chang...
___________________________________________________________________
Air-Traffic Control Is in the Midst of a Major Change from Radar to
GPS
Author : dsgerard
Score : 111 points
Date : 2020-01-24 14:56 UTC (8 hours ago)
(HTM) web link (www.wsj.com)
(TXT) w3m dump (www.wsj.com)
| jrockway wrote:
| 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 radar and
| secondary radar in addition to ADS-B information.
|
| You could probably cause a lot more trouble by 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.
|
| Ultimately the system comes down to many systems working
| together, not one stream of commands between two computers.
| redis_mlc wrote:
| > 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.
| tjohns wrote:
| 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. ;)
| wrycoder wrote:
| 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.
| cbanek wrote:
| Are they also getting rid of VOR for navigation?
|
| https://en.wikipedia.org/wiki/VHF_omnidirectional_range
|
| (Sorry, paywall is blocking me)
| korethr wrote:
| So then if everything goes to ADS-B and GPS, doesn't that
| create a potential single-point-of-failure scenario, as isn't
| the data that ADS-B sends out itself derived from GPS? Having
| all navigation information come from a single source strikes
| me as about a good idea as the single AoA sensor on the
| 737MAX.
|
| I'd like to be wrong about this, but I'm not sure how I am.
| How am I potentially wrong about this?
| l31g wrote:
| In addition to the systems you mentioned, many commercial
| aircraft are equipped with an Inertial Navigation System[0].
|
| [0] https://aviation.stackexchange.com/questions/43283/do-
| todays...
| jiveturkey wrote:
| > Air traffic controllers have primary radar and secondary
| radar in addition to ADS-B information.
|
| Article is pay-walled so I didn't read, but the title
| explicitly says ' _from_ Radar _to_ GPS ', ie away from Radar
| altogether. It doesn't say, GPS to supplement radar.
| FabHK wrote:
| > 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.
| qrbLPHiKpiux wrote:
| But the risks and consequences are catastrophic. The Feds
| will put you away forever for even attempting it.
| TkTech wrote:
| 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 to walk around for a
| bit to triangulate it.
| echelon wrote:
| Imagine an unlicensed drone emitting GPS radio signals.
| Just a small amount of sophistication and an attacker can
| do an incredible amount of harm.
| asteli wrote:
| If you live in Florida, you can go down to the pawn shop,
| buy a gun, drive over to the airport and start shooting
| at planes. Doesn't take much sophistication to cause a
| lot of harm.
| tropo wrote:
| 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.
| AWildC182 wrote:
| These could be pretty easily defeated through a multitude
| of tactics. They're just being pitched as a stop gap
| solution against the low hanging fruit like morons with
| drones or a drunk person with an airband handheld.
| voxl wrote:
| While true, you'd think state sponsored terrorism wouldn't
| care about sacrificing a few people.
| TheSoftwareGuy wrote:
| 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.
| vkou wrote:
| What kind of state sponsored terrorism? Black ops
| programs? Air forces dropping bombs? Assassinations and
| decapitation strikes?
|
| Or are we talking about the boogieman that is an excuse
| for all sorts of paranoid crackdowns, expenditures, and
| questionable legislature?
|
| Who exactly are you afraid will sponsor radio jammers at
| airports, and why do you think they will do so?
| Patrick_Devine wrote:
| 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-Talk button on the yoke had become stuck and we were
| transmitting the entire time while attempting to diagnose
| what was wrong. This happened for about five minutes.
| Thankfully he had a handheld radio in his flight bag, and
| when we turned it on we figured out really quickly what was
| going on.
|
| In that scenario, if we didn't have the handheld radio, it
| would have caused a worse problem.
| leetrout wrote:
| Now I'm trying to remember if the radios have TX lights
| that would help show that you are transmitting...
| briandear wrote:
| G1000/G3000 radios do. TX and RX
| ddoolin wrote:
| Yes, even many old school radios will have something that
| indicates transmitting or not.
| danaliv wrote:
| 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.
| Patrick_Devine wrote:
| 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.
| xxpor wrote:
| Here's an example of a AA B757 in essentially that exact
| situation after taking off at JFK:
| https://www.youtube.com/watch?v=Wcq6KipBOro
| tdhoot wrote:
| Pilots do train for communication failures. ATC at most
| airports has a number you can call to be patched through if
| your radio stops working and I've heard multiple cases of
| people having to use it.
|
| In the worst case, there are non-verbal methods of
| communication that pilots or ATC can employ (ATC can send
| light signals, pilots rock their wings to signal
| communication failures, etc.)
| AWildC182 wrote:
| 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
| Scoundreller wrote:
| Wiarton is pretty far from Toronto. But I dunno how many
| receiving/sending antennae they have for << Toronto Centre
| >>.
| AWildC182 wrote:
| 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
| korethr wrote:
| I'm kind of wondering if there even needs to be. If you keyed
| up on frequency near a major airport as described in the GP,
| I'm pretty sure the FAA and FCC would be working together to
| track you down in short order. I could see the argument that
| it would be good to add authentication to the radios to
| complement the strict enforcement for a sort of belt-and-
| suspenders approach. However, I think a more pressing concern
| for aviation radio is that is is kept simpler, and thus with
| fewer failure modes, and thus more reliable Because when you
| need that radio in an emergency, that has to be the worst
| possible time to have to deal with authentication hiccups.
| LargoLasskhyfv wrote:
| Could they? A moving target? Say the soundproofed back of
| some van.
| zentiggr wrote:
| 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 another commenter that aviation radio
| systems should be the simplest, most reliable systems
| possible, and have that layer of communication depend on
| proper radio call discipline and no more.
| LargoLasskhyfv wrote:
| 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.
| jcrawfordor wrote:
| VHF radios are relatively easy to locate by direction
| finding techniques, using for example a doppler direction
| finding array. The FCC's enforcement division is well-
| known to possess SUVs with this kind of equipment
| discreetly installed, although due to their famously
| limited budget you aren't too likely to see one in the
| wild. On the other hand, though, many large airports have
| such equipment permanently installed (e.g. RFEye).
| briandear wrote:
| https://www.telegraph.co.uk/travel/destinations/oceania/aust.
| ..
|
| It happens rarely, but pilots are also trained to not blindly
| follow clearances. They are still pilot in command.
| MereInterest wrote:
| 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
| danesparza wrote:
| Also: Spoofing is not theoretical. It has already been done:
| https://www.wired.co.uk/article/black-sea-ship-hacking-russi...
| blhack wrote:
| Not even spoofing the receiver; spoofing what the aircraft
| sends to the base station.
| supernova87a wrote:
| Well, as in the beginning of wifi/cell networks and all such
| similar technologies, their priority was to make a first
| adequate and reliable system that reports position. And
| getting operators to adopt it. Defeating bad actors was not a
| major requirement.
|
| Maybe if it's shown to be a great practical problem, they'll
| address it. If not, then no they won't. I'm guessing they
| won't.
| throw0101a wrote:
| 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
| [deleted]
| ZguideZ wrote:
| I was an ATC from 1990-1994 - we were using equipment from the
| 1960s then and I've heard it hasn't gotten much better - granted
| I was in the Marines - not the most high tech bunch, but still -
| we were civilian certified. I was never scared to fly before I
| knew who the other controllers were - an upgrade will be very
| welcome - except then you might freak out when you know who is
| building the software...
| neonate wrote:
| http://archive.md/6rZFp
| capkutay wrote:
| I hope we can finally see some improvements at SFO. The fact that
| the slightest impact on visibility can cause 4-5 hour long delays
| is ridiculous. the SF government has tirelessly blocked all
| attempts to fix the runways so that planes can land in visibility
| conditions (fog/rain) with the promise that technology would
| solve the problem.
| briandear wrote:
| The problem isn't the airport. It's the lateral separation
| requirements for IFR aircraft on the ILS. Most airliners can
| land in 0-0, but you can't do 0-0 landings on parallel runways
| with the ILS because of lateral separation requirements.
|
| There is also flow control that is from the FAA -- under IFR
| the acceptance rates are reduced.
|
| The short answer isn't that SFO isn't "upgraded" but the rate
| of aircraft acceptance is reduced under low visibility
| conditions per the FAA -- and for good reason, separation of
| aircraft.
|
| Here is more explanation:
| https://media.flysfo.com/media/sfo/media/weather-operations-...
| prostaff wrote:
| Cool Site! www.aeroworxglobal.com
| onepremise wrote:
| 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.
| JoeAltmaier wrote:
| 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.
| BeeOnRope wrote:
| Why do truckers have GPS jammers?
| burundi_coffee wrote:
| You either didn't see the comma or you're joking
| BeeOnRope wrote:
| I'm pretty sure I parsed it correctly. It's "Truckers (with
| GPS jammers) who drive my airports...". Parsing it as a
| list means it no longer makes sense.
| mft_ wrote:
| Don't think they're wrong in their interpretation. Why
| would a trucker _without_ a GPS jammer driving by an
| airport cause an issue?
| myself248 wrote:
| So their corporate telemetry system doesn't document their
| long lunch at the strip club which, for other reasons,
| happens to be located just around the corner from the
| airport.
| vijayr02 wrote:
| https://gizmodo.com/jamming-gps-signals-is-illegal-
| dangerous...
|
| > he's seen truckers trying to avoid paying highway tolls,
| employees blocking their bosses from tracking their cars,
| high school kids using them to fly drones in a restricted
| area, and even, he believes, undercover police officers using
| them to avoid tails
| AviationAtom wrote:
| Don't forget the Kremlin spoofing the local airport to try
| to keep drones from flying near their government buildings!
| RyJones wrote:
| To defeat "the Qualcomm", which records hours. This may let
| them drive longer than the DOT allows.
| tyingq wrote:
| Beating DOT legalities, hiding things like side trips to
| casinos/mistresses/bars from the boss, general dislike for
| big brother, etc.
| amluto wrote:
| 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.
| jandrese wrote:
| 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.
| tropo wrote:
| 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.
| jandrese wrote:
| Yes the antenna pattern will attenuate the signal coming
| from the ground somewhat, but it also doesn't suffer from
| 182 dB of freespace attenuation like the real signal. It
| doesn't have to bounce off of an airplane either, the
| Earth has a layer of atmosphere around it that gets
| ionized by the sun and is also full of water vapor. We
| also don't have the ability to build perfect antennas,
| especially since it has to cover the entire sky (GPS
| antennas do not physically track the individual
| satellites).
| jaywalk wrote:
| > Even the GPS signal itself has latency and lag
|
| What do you mean by this? You sound pretty knowledgeable, so
| you must know that it's simply not possible for the GPS signal
| to have latency or lag.
| zentiggr wrote:
| It's actually impossible for GPS to show your current
| position.
|
| The signals have to be received from each satellite, then
| processed to yield a position valid at the time of
| transmission.
|
| Every GPS fix you get is delayed by AT LEAST that processing
| time. Any filtering adds more lag.
|
| Most navigation systems look at the T(fix) -> T(now)
| difference and project your now position from the prior
| fixes. Especially if you're following driving directions as
| opposed to free movement, then programs like Maps etc project
| how much further you've moved on the route, not just along
| your velocity vector.
|
| After a few seconds, though, that projection will stop
| moving, too, when the gap between last fix and now gets too
| large.
| jaywalk wrote:
| The position output by a GPS receiver certainly can (will)
| have lag. That's probably what the poster I replied to was
| referring to, and I hadn't thought about it.
| aidenn0 wrote:
| Not the poster, but while the GPS signal doesn't have lag,
| many receivers run the output through a Kalman filter for
| higher precision.
| jcrawfordor wrote:
| The ATC scenario has significantly more relaxed requirements
| than ILS, and this change is intended primarily to provide
| coverage in situations where there is no, or limited, coverage
| from conventional methods (primary/secondary radar), and likely
| ultimately to replace the outdated secondary radar system with
| a space-based one.
|
| ADS-B is not a guidance tool and will not lead to any more
| usage of GPS for guidance than is currently common - and
| certainly won't impact ILS. They're just totally different use-
| cases.
| rocqua wrote:
| How long until radar becomes an afterthought, and we get an issue
| because a transponder has failed?
| sparker72678 wrote:
| This isn't about throwing away radar, it's about augmenting the
| current system with more accurate data for better and safer
| management of airspace.
|
| Existing non-ADS-B based traffic management requires accurate
| altimeters and working transponders; we have always been at the
| mercy of systems that can fail. One of the many reasons for the
| substantial training of pilots.
| tastygreenapple wrote:
| Probably a very long time, there are national security reasons
| to keep American airspace under constant radar coverage and
| radars get cheaper and better as time goes on.
| knodi123 wrote:
| I took flight school a few years ago, and had to learn to tune
| in non-directional radio beacons, and use VHF Omni-Directional
| Range tools for navigation. I wasn't allowed to use the GPS
| until I demonstrated mastery of the others.
|
| Considering that, I suspect the aviation industry will keep
| both systems working for a surprisingly long time.
| Someone wrote:
| This isn't for pilots to know where they are, it's for air
| traffic control to know where planes are.
|
| If GPS were to become the sole way to do the latter, every
| airplane would effectively get an invisibility cloak that
| those who want to do evil can activate (and even worse.
| Switching off the on-board transmitter is less scary than
| spoofing signals)
|
| Because of that, I would expect they keep using some way to
| detect planes that don't tell them where they are, or radios
| broadcasting "plane P is at X,Y,Z" without a plane being
| there.
| ceejayoz wrote:
| > If GPS were to become the sole way to do the latter,
| every airplane would effectively get an invisibility cloak
| that those who want to do evil can activate...
|
| This is already the case. Much of the civilian radar system
| already relies on transponders to get a good fix on
| aircraft, via secondary radar. Primary radar coverage (no
| transponder required) is much more limited. Turn off the
| transponder and you'll largely disappear from ATC's
| screens.
|
| ADS-B isn't new in this regard.
| mattlutze wrote:
| 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?
| o-__-o wrote:
| 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
| sokoloff wrote:
| > track all FAA registered planes
|
| I very much doubt that we'll get to even 80% of the fleet of
| FAA registered airplanes having ADS-B out by 2030. We're at
| about 50% right now.
|
| https://www.faa.gov/nextgen/equipadsb/installation/current_e.
| ..
| mattlutze wrote:
| 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...
| ceejayoz wrote:
| It's been live for years.
|
| https://flightaware.com/live/
|
| Any time my dad takes his personal plane up for an hour's
| flight, I get a text message and can watch his track (and
| altitude/speed) in real-time.
| jcrawfordor wrote:
| It's worth noting that this kind of data isn't published
| by the FAA - rather, ADS-B transponders openly transmit
| information and anyone who wants to is (at least
| technically) free to receive it. This includes commercial
| and hobbyist networks of receivers that report
| information to web services like this.
|
| The FAA in the US does publish a 'privacy list' of
| aircraft whose owners have requested that they not be
| included in services like this, and most commercial
| providers comply with that list, but enforcement is
| sparse and several hobbyist projects (e.g. ADS-B
| Exchange) do not and even emphasize aircraft that have
| put in such a request, since the tend to be a bit more
| interesting. A bit of a Streisand effect.
|
| The same situation exists with the similar AIS system
| used by ships at sea, and has produced concerns over
| malicious use, but there continue to be plenty of
| websites that will show you maps of ship locations picked
| up by their contributing AIS receivers.
| mc32 wrote:
| So no more low flying smugglers into and out of
| Canada/Mexico... wonder how they will adapt (beside going
| dark though they'd notice someone going dark after takeoff).
| simonswords82 wrote:
| They simply won't turn their GPS on.
| mc32 wrote:
| Won't they have to before takeoff? Or will that not be a
| requirement?
| sokoloff wrote:
| The _overwhelming majority_ of airspace under 10K feet in
| the US does not require ADS-B out.
|
| https://www.faa.gov/nextgen/equipadsb/research/airspace/
| simonswords82 wrote:
| They'll ignore the rules as I'm sure they already do.
|
| As you'll see from the various documentaries,
| historically planes operating illegally and/or doing
| illegal things will fly "under the radar" and keep their
| transponder turned off to evade the authorities.
|
| They'll do the same thing with GPS.
| ssully wrote:
| The people doing illegal activity with planes don't care
| about requirements or are paying people to overlook them
| ignoring the requirements.
| jellicle wrote:
| Drug smuggling planes might not be in full compliance
| with every single regulation.
| sgc wrote:
| 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.
| lozaning wrote:
| 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?
| sgc wrote:
| That is one way, but sometimes they do show up / try to
| mimic other traffic / etc. That part of things would be
| reduced.
| throw0101a wrote:
| > Now you will be able to track all FAA registered planes
|
| Almost all.
|
| If you're flying VFR you can put your transponder into an
| anonymous / incognito mode (if it supports it):
|
| * https://www.avweb.com/aviation-news/faa-acts-to-preserve-
| ads...
|
| If you want IFR or flight following you'll have to de-
| anonymized, which is no worse than it was before ADS-B.
| rhacker wrote:
| > allowing more planes in the air
|
| So that's a good thing? interesting.
| GnarfGnarf wrote:
| When the Kessler syndrome occurs, all transportation will grind
| to a halt.
|
| The Kessler syndrome is when collisions between objects cause a
| cascade in which each collision generates space debris that
| increases the likelihood of further collisions.
|
| https://en.wikipedia.org/wiki/Kessler_syndrome
| akiselev wrote:
| GPS satellites are in geosynchronous orbit, far above any
| threat of Kessler syndrome and we won't have nearly enough
| material in orbit that occlusion of the satellites would become
| a problem for centuries, if ever.
| missosoup wrote:
| If there's ever a hot world war again, all global navigation
| constellations are going to be destroyed with ASAT missiles
| in the first hour of it.
|
| There's a legitimate concern that over-reliance on GPS will
| cause massive financial and loss of life damage in the
| civilian sector if it's ever denied through jamming or
| kinetic attacks or solar storm etc.
| jessriedel wrote:
| This may be true, but note that all the ASAT missle
| demonstrated to date are only capable of low-Earth orbit,
| just a couple thousand km from the Earth's surface. The GPS
| satellites operate at tens of thousands of kilometers
| higher altitude in medium Earth orbit.
|
| https://www.reuters.com/article/us-china-space-
| report/analys...
| missosoup wrote:
| Demonstrating ASAT against a GEO target would cause a
| major political incident. The LEO ASAT tests carried out
| to date caused enough outcry as is. Hitting a GEO target
| is not difficult. Ignoring dedicated ASAT missiles, any
| modern IRBM or LRBM can be tasked to intercept a GEO
| target.
|
| Global navigation constellations are certainly going to
| be one of the first targets in any major hot conflict
| between world powers.
|
| Realistically, a solar storm is a more likely and less
| predictable threat. The end result is the same, any
| critical functionality that relies on GPS will be denied
| for a prolonged period of time.
| jessriedel wrote:
| > Hitting a GEO target is not difficult. Ignoring
| dedicated ASAT missiles, any modern IRBM or LRBM can be
| tasked to intercept a GEO target.
|
| Do you have a cite for this?
| sigstoat wrote:
| just fyi, they're in medium earth orbit, thousands of
| kilometers below geosynch. it's why you have to have an up to
| date almanac, to know which satellites you can see right now,
| and why cold starts used to take so damn long. (listen for 4
| satellites at a time, trying to figure out which ones are
| there, when you have no idea when or where you are.)
|
| (though i agree that kessler concerns are overblown.)
| jessriedel wrote:
| GPS satellites are indeed at much higher altitudes and thus
| well protected from (highly speculative) worst-care Kessler
| syndrome scenarios, which occur in low-Earth orbit (<2,000 km
| altitude). However, GPS satellites are not in geosynchronous
| orbit (35,7000 km altitude) but rather operate in a medium
| Earth orbit of about 20,000 km.
| tialaramex wrote:
| Indeed. The GPS birds zip around, a GPS device has to learn
| (traditionally from GPS itself but downloading from the
| Internet is much faster if you have Internet and these days
| most devices can do that) where the birds are in order to
| turn its relative distance from each satellite into an
| absolute position on the Earth's surface.
|
| If you have an actual GPS app there's typically a
| diagnostic screen where can see where the satellites are
| and see them arrive and disappear from your perspective as
| they orbit.
| cgidriver wrote:
| Why would you change to GPS - when it is so easy to spoof/jam?
| coldcode wrote:
| The same GPS the US Government reserves the right to reduce the
| precision when they feel like it? Seems risky idea to assume they
| will never do this.
| sparker72678 wrote:
| This isn't about using GPS as the only navigation aid in an
| airplane. It's about _augmenting_ the current air traffic
| system with additional, more accurate data to help manage
| airspace.
|
| ADS-B doesn't change anything about how a plane navigates.
| That's still done with a plethora of redundant instruments, all
| working together.
| throw0101a wrote:
| > reduce the precision
|
| GPS satellites will not have the hardware to do selective
| availability in GPS III, which are currently being launched:
|
| *
| https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_...
| iwalton3 wrote:
| That is known as Selective Availability and according to the US
| Government there is no intention of enabling it again [1]. New
| GPS satellites are apparently being built without the Selective
| Availability capability [2].
|
| [1] https://www.gps.gov/systems/gps/modernization/sa/faq/#on
| [2]
| https://archive.defense.gov/releases/release.aspx?releaseid=...
| wffurr wrote:
| I would hope aircraft would have multiband receivers that also
| support GLONASS, Galileo, and BeiDou. There's also Japan's QZSS
| and the regional Indian IRNSS.
| gsich wrote:
| Probably depends on how old the stuff is.
| kevstev wrote:
| Isn't low precision something like +/- 15 feet? For ATC, that
| seems more than good enough when they keep jets a mile+ apart.
| It just needs to be more precise than radar.
| Johnny555 wrote:
| The government claims that they won't enable selective
| availability any more (which is less useful as a protective
| mechanism anyway since multi-protocol receivers can use GPS /
| Galileo / GLONASS / Beidou).
|
| But if SA was enabled:
|
| _Before it was turned off on May 2, 2000, typical SA errors
| were about 50 m (164 ft) horizontally and about 100 m (328
| ft) vertically_
|
| https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_.
| ..
| jomoio wrote:
| There are also ground based systems at airports which
| increase reliability / integrity for things like simultaneous
| parallel approaches. [1] says to within +/- 1m horizontal and
| vertical.
|
| [1] https://www.skybrary.aero/index.php/Ground_Based_Augmenta
| tio...
| griffinkelly wrote:
| 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-...
| reaperducer wrote:
| Not just for exercises. There are places in America where it's
| permanently jammed, most often near military bases.
| briandear wrote:
| 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.
| opwieurposiu wrote:
| 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.
| jandrese wrote:
| 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.
| yingw787 wrote:
| 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!
| sparker72678 wrote:
| This isn't about throwing away radar, it's about augmenting the
| current system with more accurate data for better and safer
| management of airspace.
|
| Most airplanes already rely heavily on GPS for their own
| navigation. If GPS is being jammed (or having any other clear
| issue) they'll fall back to their many other redundant
| navigation instruments.
|
| If you want to be scared, be scared about spoofing of ILS
| signals, where a couple of dozen feet of error can be fatal.
|
| https://arstechnica.com/information-technology/2019/05/the-r...
| throw0101a wrote:
| > This isn't about throwing away radar, ...
|
| *all radar.
|
| Certainly around airports radar will be kept, but there are a
| few (remote?) places where aging infrastructure will not be
| replaced.
|
| On the plus side, there are areas that had no coverage (Gulf
| of Mexico) which now get traffic information from receivers
| that are easier to run than radar towers.
| elil17 wrote:
| I'd feel a lot more comfortable if they retained RADAR as a
| backup - why not have both?
| stephen_g wrote:
| I can't read the article (paywalled), but I would expect
| primary radar isn't going anywhere around airports.
|
| We still have it, and our commercial planes have been
| required to have ADS-B transponders here for more than a
| decade. This is just for en-route tracking.
| sokoloff wrote:
| Where is "here" that's required ADS-B for over a decade?
| adventured wrote:
| They're not doing away with radar and it's not going to be a
| backup. They're going to use both.
| freeone3000 wrote:
| 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.
| gruez wrote:
| >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?
| freeone3000 wrote:
| 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).
| gruez wrote:
| The keyword here is spoof. There's no doubt that you can
| jam the ground receiver (both radar and ADS-B). The key
| question is whether you can spoof radar returns as easily
| as ADS-B transmissions.
| tastyfreeze wrote:
| Well some stealth is base on spoofing part of a radar
| return. Absorb as much of the incoming radar as possible
| and alter the reflection using a phased array. So its not
| impossible just more expensive.
|
| According to the crew on the USS Zumwalt they can make a
| 600' ship look as large as a cruise ship or as small as a
| fishing vessel. This ship is covered in radar absorbent
| materials and has a giant phased array to accomplish this.
| adatavizguy wrote:
| We still maintain Loran C[0]. Interesting to note receivers
| have been developed to grab the radio signal from all available
| stations, up to 40, and triangulate location with eLoran. It's
| a nice to have as backup to GPS however I'm not sure if it is
| effective against jamming or spoofing. So, the navy still
| teaches celestial navigation to officers. [1]
|
| EDIT: Apparently Loran C was discontinued in 2010.
|
| [0]https://en.wikipedia.org/wiki/Loran-C [1]
| https://www.stripes.com/news/break-out-the-sextant-navy-teac...
| sokoloff wrote:
| > We still maintain Loran C
|
| What does "still maintain" mean in this context? My Loran-C
| receiver stopped working years ago when we turned off the
| signals.
|
| https://en.wikipedia.org/wiki/Loran-C#Loran-
| C_in_the_21st_ce...
| jcrawfordor wrote:
| Loran-C has been discontinued. However, there are occasional
| ongoing proposals to restore it as "eLORAN" using newer
| digital transmitting and receiving equipment, to provide a
| terrestrial backup for GNSS. These have mostly fallen flat
| for simple funding reasons, but increasing attention to ASAT
| warfare keeps discussions going.
| gryphonshafer wrote:
| A valuable part of the ADS-B out mandate is that planes even as
| small as mine (a.k.a. tiny) can cheaply (<200$US) pick up ADS-B
| in and display it on a consumer tablet. My private airplanes now
| have pseudo radar. Not every airplane in the air is broadcasting,
| but most are. This is a huge safety win. Almost without exception
| I'll see airplanes on my tablet long before I have visual on
| them.
| AviationAtom wrote:
| Linkage to what is most likely being referenced here, for the
| curious: http://stratux.me/
| sokoloff wrote:
| Without ADS-B out on your airplane (which you don't have for
| <$200), you will only pick up mode-C traffic in your area if
| there's another airplane nearby with ADS-B out and coded to
| receive ADS-B in. You would then be intercepting/"piggybacking"
| the traffic transmissions meant for that airplane.
|
| https://ipadpilotnews.com/2019/09/ads-b-traffic-when-does-it...
|
| https://www.faa.gov/nextgen/programs/adsb/faq/#x8 You probably
| have a much large hole in your coverage than you thought.
| ryandrake wrote:
| Fortunately (unpopular opinion among pilots) the FAA is
| slowly phasing in ADS-B out as required equipment. Starting
| Jan 1 of this year, you need to tx ADS-B if you're anywhere
| you'd otherwise need a Mode-C transponder, including around
| many airports.
| sokoloff wrote:
| Nit: Starting Jan 2
| JoeAltmaier wrote:
| Lots of important cautions posted in this thread.
|
| On the plus side, lots of opportunity to create cockpit displays,
| warning devices etc to increase pilot safety!
| JoeAltmaier wrote:
| Really! I'm working a contract on a cockpit device now, for
| this new requirement.
| code4tee wrote:
| 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).
| UncleOxidant wrote:
| Oh, good. I can't read the article (paywall) but was hoping
| they weren't actually replacing radar with GPS. Using GPS to
| enhance radar seems a lot better.
| danaliv wrote:
| 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.
| cmurf wrote:
| ADS-B and Mode A/C/S (MSSR) are both secondary radar. but the
| equipment differs, in particular the ground equipment looks
| different. It could be that the MSSR equipment gets phased out
| as ADS-B prevails. Primary radar will continue to be used
| though, in particular at airports (ones other than the many
| local uncontrolled variety).
| ufmace wrote:
| 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 already in a world were ATC
| info could be spoofed.
| derstander wrote:
| Note: I only have limited experience with ATC Radar (small
| number of models in the US).
|
| Based on my experience, ATC Radar have no difficulty seeing
| commercial aircraft with a high probability of detection and
| low probability of false alarm.
|
| Source: completed a performance assessment of several such
| systems in the early 2000s against their legacy counterparts
| using aircraft beacon systems as a source of "truth".
|
| If I remember to come back to this later, I'll write a little
| post showing the theoretical detection performance of such a
| system. If you'd like to try the exercise yourself, the
| relevant worksheet is a Blake Chart and you can look up
| surrogate parameters for the Radar via checking the ASR-XX
| pages on Wikipedia (e.g. ASR-9 or ASR-11). Finding Radar cross
| sections (RCS) for commercial aircraft models is similarly
| straightforward. The system is logarithmic so as long as you're
| in the ballpark you'll be close.
| jcrawfordor wrote:
| 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 to detect soviet aircraft. It has a reduced equipment
| footprint, but this is generally due to improving radar
| technology, coverage is similar and the backend data processing
| systems are much more advanced. The majority of radar sites
| belong to and are maintained by FAA but report directly to the
| Air Force air combat system.
| ufmace wrote:
| 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.
| jcrawfordor wrote:
| 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 of relying on the radar returns which even in
| areas with good coverage can sometimes come in and out and
| generally be finnicky.
|
| Consider that controllers currently rely primarily on
| secondary radar, which while more difficult to spoof than
| ADS-B is still quite subject to malicious manipulation.
| They are well aware that a primary radar return with no
| corresponding secondary radar information is something to
| sort out, and this won't change with a switch to ADS-B.
| briandear wrote:
| 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.
| jessaustin wrote:
| 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
| jcrawfordor wrote:
| 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.
| madengr wrote:
| Is that in MO? There is a similar one near Belton. I
| believe it is C band radar. The FCC database should have
| it.
| Rochus wrote:
| 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?
| tux1968 wrote:
| 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/
| jrockway wrote:
| I pay for the Wall Street Journal, so had no trouble reading
| the article.
|
| Not everything in life is free.
| Merrill wrote:
| >GPS JAMMING EXPECTED IN SOUTHEAST DURING MILITARY EXERCISE
|
| >GPS reception may be unavailable or unreliable over a large
| portion of the southeastern states and the Caribbean during
| offshore military exercises scheduled between January 16 and 24.
|
| https://www.aopa.org/news-and-media/all-news/2020/january/14...
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