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Comment by kevin42 | Hacker News Reader

I have an amateur built experimental airplane, and on my first flight, GPS wasn't working. It was working on the ground, so I figured a bad coax cable or something from the vibration. When I landed it started working again, but later in the day it wasn't. A few days later I found out that the nearby Air Force base was testing GPS jamming, and there was even a NOTAM about it.

There's a site that tracks GPS jamming: https://gpsjam.org/

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Wanted to highlight how GREAT the FAQ section is on that page. It feels like each question on that list is one that the author actually received and answered in an easy to understand format.

Makes me wish for the early days of the Internet where FAQ writing was good practice and writing a great FAQ was considered something worth celebrating.

Thank you! I haven't updated that page in a long time, and there are a few things I should add. Some possibilities:

* Does this map show spoofing? No.

* How come sometimes I see aircraft flying over Ukraine? That's GPS spoofing.

* [Add Myanmar & Kashmir to the list of conflict zones.]

I wish that website had some kind of timelapse functionality. It would be very useful to see how jamming in an area changes over time.

There are multiple sites that try to infer whether jamming is happening.

https://gpsjam.org/

https://spoofing.skai-data-services.com/

https://www.flightradar24.com/data/gps-jamming

Ukraine is of course a huge hotbed of jamming, but every time I've looked, there's been jamming on the US/Mexico border and a bit north of Texas around an airbase.

There's also a lot of info available here: https://www.nstb.tc.faa.gov/

The apparent interference in Texas is almost always fighter pilots doing training. During aggressive maneuvering the aircraft fuselage can mask the GPS antenna, causing the aircraft to lose GPS accuracy.

Fighter jets emit ADS-B? I know it's only training, but I'm curious?

Go to https://globe.adsbexchange.com and once it loads, press "u" to show only military aircraft. You'll see bunches of helicopters, transports and tankers, trainers like T-6 Texans and T-38 Talons, and once in a while an actual fighter or ground attack aircraft.

adsb.exposed has a dedicated section on F-16: https://adsb.exposed/?zoom=5&lat=43.4805&lng=-110.7608&query...

I'm thinking about adding that. (Donations help, see the About page.)

Is it common practice to go flying without checking for a NOTAM that might impact your intended route? (I'm not trying to insult you or anything, I'm not a pilot and don't know the standard procedures for dealing with those.)

Should you brief the NOTAMs? Yes. Is it common to miss one? Also yes. Go look at the ATC YouTube channels and you will find lots of people being intercepted by fighter jets even though they use Foreflight.

Another problem is NOTAM spam; it seems like, in some areas, there are a bunch of NOTAMs that aren't very important but that you still have to read through to see if they're relevant. "We're testing GPS jamming" or "we will send a fighter jet if you fly into this rectangle" look a lot like the more common "taxiway T at Middle Of Nowhere Municipal Airport is out of service until 1/1/2038".

Could be a good opportunity for using an LLM to summarize and extract anything important?

Here’s a critical NOTAM that was missed. Translated, it means, if you fly here, the Russians will shoot your ass down. And so they did. But nothing encodes that information in the NOTAM so there is nothing for an LLM to summarize and extract. Expecting an AI to compensate for poor system design is magical thinking.

A1492/14 NOTAM Q) UKDV/QRTCA/IV/BO /W /260/320/4822N03807E095 A) UKDV B) 1407141800 C) 1408142359EST E) TEMPO RESTRICTED AREA INSTALLED WITHIN FIR DNIPROPETROVSK BOUNDED BY COORDINATES : 495355N 0380155E 485213N 0372209E 480122N 0370253E 471352N 0365856E 465018N 0374325E 465900N 0382000E 470642N 0381324E THEN ALONG STATE BOUNDARY UNTIL POINT 495355N 0380155E. RESTRICTION NOT APPLIED FOR FLIGHTS OF STATE ACFT OF UKRAINE. F) FL260 G) FL320)

Besides that, would the developer of the LLM accept liability for accidentally filtering out important NOTAMS, or hallucinating NOTAMS that did not exist?

That looks less like poor system design (although I'm sure that's contributing) and more like understatement that's practically criminal. Who the hells hears "Russia may shoot down your plane if you go here" and thinks they should convey it via "tempo restricted area bounded by coordinates"? That's like posting a "do not enter" on a door with a bomb behind it. Is English so hard?

For pilots, "restricted area" is already synonymous with "absolutely do not even think about going here" and is used for things like military testing and training areas that regularly use live ammo, extremely sensitive military or bases, etc. As a concrete example, Area 51 is in a "restricted area".

> For pilots, "restricted area" is already synonymous with "absolutely do not even think about going here"

I don't buy it. How often do you hear of a passenger plane getting shot down for entering restricted airspace over peaceful territory like the US? What about over combat zones, like over Ukraine or Russia? Who in their right mind equates these as as equally severe? If you had to make an emergency landing would you seriously view these equally?

At least within the US, entering a restricted area without authorization can result in your own personal military air show, followed by lots of questioning, possibly prison, losing your license or both. You don't mess around with restricted areas unless you have a damn good reason.

>> I don't buy it. How often do you hear of a passenger plane getting shot down

> At least within the US, entering a restricted area without authorization can result in your own personal military air show, followed by lots of questioning, possibly prison, losing your license or both. You don't mess around with restricted areas unless you have a damn good reason.

You're not taking my point.

I don't know about you, but I would sure as hell prefer prison over myself and hundreds of other people falling from 40,000 feet.

> ...I would sure as hell prefer prison over myself and hundreds of other people falling from 40,000 feet.

On the one hand, that would be ideal.

On the other hand, that appears to be a NOTAM restricting access to an active war zone. It is truly tragic, and should be avoided whenever reasonably possible, but sometimes civilians who enter war zones get killed.

So, (just so you know) the "they flew into an active war zone" bit is probably the reason why your point is being brushed aside. Restricted airspace is restricted airspace. Unless you're on the unrestricted craft list, you simply don't enter it.

To my reading it's very understated if that is the entire text of the NOTAM - I would have liked it to say WAR ZONE or GUIDED MISSILES in there somewhere.

Compare it to the DC SFRA[0] which specifically states "MAY USE DEADLY FORCE" even though that's extremely unlikely to happen.

When Flight Restrictions are active in FAA controlled airspace, ATC will often clear you through them if you're on an appropriate flight plan without you needing to ask. Even the 'deadly force' SFRA above is essentially handled for you so long as you file an IFR flight plan.

[0]: https://www.faa.gov/air_traffic/publications/us_restrictions...

When I'm flight planning and I see a restricted area along my route, I honestly don't need to know why. I'm not going there unless the controlling agency gives me authorization and I understand the danger. Because there is danger; otherwise it wouldn't be restricted.

If it makes you feel better, here's the current TFR over eastern Ukraine. It even explicitly says "danger" - does that make you feel better?

TEMPO DANGER AREA ACT WI COORD: 434800N0392400E-433000N0303500E-441500N0302500E-...

There are more risks than getting shot down. All sorts of dangerous activities may be going on in restricted areas: missile launches, dogfights between fighter jets, tests of unmanned vehicles, etc. You don't want to be a surprise guest at any of them. "Restricted" is a single, short word taught in pilot school to get the message across clearly. If a sudden emergency requires entering a restricted area, then air traffic controllers are there to coordinate it.

I mean, I just copy/pasted that into ChatGPT with no other instructions or context, and it seemed to handle it pretty well:

This NOTAM (Notice to Airmen) establishes a temporary restricted area within the Dnipropetrovsk FIR (Flight Information Region) in Ukraine. The restricted airspace is defined by specific geographic coordinates, forming a boundary for the restricted area.

Key details include:

- *Effective Dates:* From July 14, 2014, at 18:00 until August 14, 2014, at 23:59, with the "EST" indicating that the end date might be subject to change.

- *Altitude Limits:* The restricted area applies to flights between FL260 (Flight Level 260, approximately 26,000 feet) and FL320 (approximately 32,000 feet).

- *Exemptions:* The restriction does not apply to flights of state aircraft of Ukraine, meaning those aircraft can operate within the restricted area during the specified timeframe.

Pilots and airline operators should be aware that flights not exempted by this NOTAM must avoid this area or adjust flight levels accordingly to comply with the restrictions. For further guidance, they should consult official aviation authorities or current NOTAM listings, considering the potential for changes.

FWIW, this exact text was probably part of ChatGPT's training data, but the next important NOTAM might not be.

Perhaps. It would be easy to past in an arbitrary one and see how it does. I'm pretty sure it has information on how to decode these in general in it's training set.

That would be impressive because there isn't a standard format for NOTAMs. They are intended for humans, not machines. It's a major problem that safety critical information is often not available in machine readable format, so you can't have a plane's navigation system automatically give warnings if you program it to fly into restricted air space or to a navigation beacon or runway that is announced as offline for maintenance by NOTAM.

I have an AI-powered NOTAM mapper at https://notam-mapper.obliscence.com. It's just intended for fun, but you can try pasting arbitrary NOTAMs into it and check the results.

For those who can't read NOTAMs: This is a NOTAM that was in effect during the MH17 shootdown, closing the airspace from FL260 (26,000 feet) to FL320 (32,000 feet.) In the previous three months, 16 aircraft were shot down in Ukrainian airspace, including one three days before at FL210, which is what prompted the NOTAM. Ukrainian officials should have closed the airspace entirely, but chose to keep it open and issue this NOTAM instead. MH17 was at FL330, so in fact it did not violate this NOTAM at all.

And for some further context: the quote upthread of "NOTAMS are a bunch of garbage that no one pays any attention to" from NTSB chairman Robert Sumwalt came after Air Canada flight 759, which would have had >1000 fatalities if two airplanes were a few feet closer: https://en.wikipedia.org/wiki/Air_Canada_Flight_759

"One lamp out of 18 on this radio tower is operating at 75% brightness" repeated every day for years

NOTAMS are a bunch of garbage that no one pays any attention to. That’s not my opinion, that’s the opinion of former NTSB chairman Robert Sumwalt. I’m sure the GPS NOTAM was buried somewhere in the 27 page NOTAM list and it probably said something like this actual current GPS NOTAM: !GPS 03/022 GPS NAV PRN 08 U/S 2503061847-2506050001

https://www.ainonline.com/aviation-news/business-aviation/20...

I was flying in and out of a private airport in uncontrolled airspace, so I didn't check. If was my first test flight so I was pretty much just circling around my airstrip.

If I'm flying cross country, in to controlled airspace, or an airport I'm not familiar with, I will. But this particular notam didn't show up when I looked at nearby airports.

This map is great,very interesting. curious that GPS is jammed over Gdansk, Helsinki and Tallinn.

It’s because they’re next to Kaliningrad, that weird Russian exclave

Another way to see that geography is as approaches into Russia. Gdansk borders Kaliningrad, Helsinki and Tallinn straddle St Petersburg.

Russia has been jamming GPS over Finland, Estonia, and Poland on and off for a couple years, and it's been at its peak now for several months. Sometimes flights have to be canceled. Tartu airport in Estonia was closed for a while[1] because the only instrument approaches it has were GPS-based.

Even worse than jamming is spoofing, which Russia also does. With jamming, you and the aircraft's systems both know what's happening. Spoofing isn't as easy to detect, as the GPS system can report the wrong location but think it's highly accurate. Spoofing (and to some extent jamming) can have a persistent effect on aircraft systems even after they move out of range of the jammer/spoofer, which can lead to degraded navigation accuracy for the rest of the flight.

It's a whole deal. Russia is messing with strategically important systems of many European countries, and decreasing civilian aviation safety, and they rarely get called on it. For a long time there was reluctance to even name Russia as the culprit.

1. https://www.heise.de/en/news/GPS-jamming-no-more-flights-to-...

> Russia has been jamming GPS over Finland, Estonia, and Poland on and off for a couple years, and it's been at its peak now for several months. Sometimes flights have to be canceled.

I feel like we had airports before we had GPS. If this is a regular thing, shouldn't we have ways of using the airport without hoping that the jamming is having an off day?

Here's one: https://en.wikipedia.org/wiki/Bubble_octant

There usually are other systems (e.g. ILS), but not always.

This post has several comments along the lines of "We used to fly without GPS and it was fine!" The fact is that aviation is so much safer than it used to be, and GPS is part of that. GPS helps aircraft navigate accurately even when they're not near an airport. It helps give situational awareness and avoid mid-air collisions (almost every aircraft these days has a traffic display that shows ADS-B positions of other nearby aircraft, and those positions come from accurate GPS).

Loss or spoofing of GPS isn't usually a critical safety issue on an aircraft, but it definitely removes layers of safety and adds additional risk. Pilots can lose that situational awareness of nearby traffic. They may have increased workload and distraction due to having to use a less familiar & less accurate means of navigation, trying to figure out why their systems aren't working correctly, and even getting bogus ground proximity warning system alerts. ATC may now have increased workload and distraction because some approaches or even runways are no longer usable.

We drove cars for a long time without seat belts and air bags, too.

> We drove cars for a long time without seat belts and air bags, too.

And if we were having problems with seatbelt jammers, everyone would instantly respond by just not using seatbelts in those areas. There would be no road closures and no trip cancellations. What are we supposed to learn from this analogy?

That aviation without GPS isn’t as safe as aviation with it.

I don't even think that's true. Seatbelts are an improvement in safety regardless of context. But what you're arguing here is that a system that's designed to rely on GPS availability, and gets it, is safer than the same system during a GPS outage, not that GPS availability will make any airport management system safer.

It makes it safer to run aircraft closer together. Most airport capacity increases these days come from optimizing airspace, not from new runways or airports, which are time consuming, expensive, and controversial. We used to operate without them but we were also generally operating a lot fewer flights back then.

The more apt analogy is what would our roads look like if all traffic signals stopped working? People would still drive, but it would have to be at lower speeds, with more congestion, etc.

> The more apt analogy is what would our roads look like if all traffic signals stopped working? People would still drive, but it would have to be at lower speeds, with more congestion, etc.

This happens pretty frequently with single signals, so we know what that looks like.

An unattended broken signal gets treated like a stop sign (by law), and this immediately blocks traffic. It's a total disaster.

If it happens anywhere near a population center, a human will be dispatched to cover for the broken signal and dysfunctional law by manually directing traffic, and this gets you almost all the way back to normal.

If every signal failed at once, that would cause much bigger problems, but in the event that we know we're unable to repair the signals, which is the case here, we wouldn't just try to muddle through using the existing roads and systems. We'd define new systems that worked better in the absence of traffic lights.

I was mostly addressing the idea expressed in other places in this thread that aviation without GPS is fine, not your specific point. To address your question, the commercial aviation world is still in the process of figuring out how to deal with the new, current reality of GPS jamming and spoofing. They're developing new procedures, designing new equipment, and changing priorities and plans. While this happens they're downplaying the risks in press releases and statements to avoid spooking the public.

"If this is a regular thing, shouldn't we have ways of using the airport without hoping that the jamming is having an off day?" Yes. But it takes time and money. This level of GPS interference is relatively new, and for about the past 30 years you could basically assume GPS would be available.

What do you mean "if" of course we do? Relying on older methods means narrowing the acceptable conditions for landing. It means reduced economic activity, reduced opportunities.

How about we treat enemies as actual enemies, rather than rolling over and letting them make our lives more difficult?

In comparison to the US's power, Russia is an annoying pipsqueak, but instead we are letting Russia boss around on everything. It's shameful and embarrassing.

Why in the world should we have to rely on inferior methods?

> How about we treat enemies as actual enemies, rather than rolling over and letting them make our lives more difficult?

Treating someone as an actual enemy means accepting that sometimes they're going to do things that are inconvenient for you.

> Why in the world should we have to rely on inferior methods?

Well...

treating someone as an actual enemy means accepting that sometimes they're going to do things that are inconvenient for you.

And they are going to also experience "inconveniences" for random bullying.

Ignoring what a bully does has predictable consequences.

Yes, I'm reminded of how woefully the teachers at my grade school tried to stop bullying by... making them sit together and talk through a script. Usually finalized by a knock on the head as they were walking out, having perfectly finished their "remediation". I'm also reminded of how quickly problems were solved when you simply disobeyed the adults and hit them back. It got results. You might say that a grade school is very different than the world state. You might

Yes, some might.

And other, far more wise people, might realize that appeasement of bullies throughout history has resulted in some of our very worst wars and the most horrific atrocities that humanity has ever committed. Weakness invites conflict and destruction from the bullies of the world, and when it comes to war, the bullies gain materials and conscripts when they are allowed to conquer.

(I think we are very much on the same page, thank you for the comment.)

Europe has about 5 functioning fighter aircraft and ~~20 operating tanks at any given moment. It is also completely controlled by a political system that considers conflict the same way it sees domestic abuse in a relationship. It's entire current zeitgeist is formed and controlled by the half of humanity that cant fight and will spend as much time as possible trying to talk their way out of it.

Your narrative on Europe is wrong. Poland has 1000 tanks and would completely wipe out Russia in a war. United, Europe could eliminate Russia's military with a few percent of GDP, full war footing is in no way essential.

They are nobles arguing about who has to take time away from the dinner party to shoo away a miscreant throwing tomatoes. Except for the Baltic States, who take it more seriously at the moment, but that will change as soon as the Vatniks on the political extremes are finally removed.

even assuming Poland could do this, what do you think Russia would do nuclear wise if they were faced with imminent destruction? Did you forget that we live under the sword of Damocles?

Additionally, good luck finding young men who want to fight for their country in the west of Europe. New arrivals will not lay down their lives as they often hate their host countries and people. Heritage Europeans are massively discriminated against by their own governments for speech crimes, on top of race and sex-based discrimination. A very small amount of men will fight to continue that state of affairs.

First, Poland is a NATO member.

Second, Ukraine is invading Russian territory, occupies it, and no nukes yet! The supposed nuclear threat is empty and stupid.

Third, if you think for a fucking microsecond that 90% of Polish men are not ready to go to war and kill Russians you have never talked to a Polish person. They know what is at stake.

Fourth, even the UK is talking about boots on the ground and planes in the air over Ukraine, https://breakingdefense.com/2025/03/amid-us-rift-with-ukrain...

Fifth, fighting these completely made up narratives that have no basis in reality is exhausting. It's almost as if an entire population has decided that they misread the commandment to be "Though SHALL bear false witness."

Poland is a NATO member, but we're not going to war if they invade Russia and then get nuked.

UK is talking about boots on the ground. Wake me up when they actually have a sustained, large-scale presence.

Europe has paid Russia more (for their natural gas) than they have given aid to Ukraine during the duration of this war. Europe is totally cooked.

You're suggesting open war with Russia over GPS jamming? You do understand that the west also engages in sub-war, antagonistic activities with Russia, right? These aren't "inferior methods", they're part of spectrum of activities which have associated costs and risks.

> I feel like we had airports before we had GPS.

one of the things that made GPS available for civilian use was the Korean Air Lines Flight 007 incident.

https://en.wikipedia.org/wiki/Korean_Air_Lines_Flight_007

Yes, airports in eastern Europe are now using the old ground based VHF radio beacons (VOR, DME and ILS).

However, they were not in use a few years ago. Some airports never had the ground based equipment installed, others still had the beacons functional but the procedures (STAR, SID) had been phased out in favor of the easier and cheaper satellite based GNSS RNAV procedures.

Some airports had brand new VHF equipment installed, others had the old procedures reinstated.

But aviation is a slow moving, risk averse, cost sensitive business so several airports were inaccessible (apart from visual approach) for a few months.

We become reliant on technology so quickly. Alternatives may not be safe in extreme weather. We have also torn down previous systems like Omega.

https://en.wikipedia.org/wiki/Omega_(navigation_system)

They are surely doing that because they want to divert NATO expansion westward /s

I’ve never seen a map that has each locality in its primary language..

It's the default OpensStreetMap style, which was never intended as a cartographic basemap for visualizations. Its purpose is to facilitate editing of the underlying data... but it's also one of the "free" options out there and integrated into most map library examples. ("free" because it's community-supported and heavy usage is discouraged, https://operations.osmfoundation.org/policies/tiles/)

GPSJAM had a non-free map for years that didn't have this issue, but as the site got more traffic I could no longer afford to pay for it.

That's fair! While understandably it isn't probably a top priority, I'd highly encourage checking out https://docs.protomaps.com/pmtiles/maplibre . It can be nearly free to directly hit a single planet pmtile file, especially with cdn in front, and slightly more to put up a server in front of it (imo, not needed).

Anyway, awesome site regardless, and OSM tiles are fine if not abusing their hosting (this isn't I'm sure).

What is that area to the right of India?

Myanmar, alias Burma. They're having a hot civil war since 2021. (They've had tensions and insurgencies for as long as they've been an independent state.)

Myanmar, which is currently a conflict zone.

Myanmar. Unstable autocracy, recent coup, ongoing uprising. A huge mess, and exactly where you'd expect the ruling party to be trying to eliminate navigation aids.

> to the right

*East

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