Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

FAA Fumbled Its Response to a Surge in GPS Jamming

spectrum.ieee.org

Post reply on HN
Print view View original

91–100 of 134 posts

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#91

Post by mywittyname »

loeg wrote: post #79
mywittyname wrote: post #49

Earlier quoted context omitted.

That doesn't entitle them to access to military systems, either individually or as a collective. And surely citizens of other countries are not entitled to access to military systems.

Surely it entitles the citizenry to access military-funded systems that do not benefit from secrecy, like GPS or the internet.

The military serves the tax payer by preserving their sovereignty.

It's nice that they allow civilian use of GPS, but it doesn't follow that they need to. It's perfectly acceptable to say that a civilian organization, government or otherwise, is responsible for providing satellite-based location services for civilian use.

The way GPS is operated is very unusual. The military doesn't provide satphone service to people around the world; are you arguing that they should?

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#92

Post by pmorici »

Crosseye_Jack wrote: post #71
takk309 wrote: post #66

Earlier quoted context omitted.

Remember, GPS is a military tool first. Civilians get to use it at the militaries discretion. They could turn the selective availability (which was turned off in 2000) back on and remove a lot of civilian accuracy. Maybe civilian pilots are the ones that need to training aids more than the military. It seems to me that they should be able to navigate without gps in a safe manner. Edit: fixed term for selective availa…

Didn't they actually remove selective availability from the new sat's that were launched. https://web.archive.org/web/20080113123316/http://pnt.gov/pu... > In September 2007, the U.S. Government announced its decision to procure the future generation of GPS satellites, known as GPS III, without the SA feature. Doing this will make the policy decision of 2000 permanent and eliminate a source of uncertainty in GPS perf…

I think it is a moot point because there are 5 position constellations now days (US, EU, China, Russia, Japan) and many popular consumer chipsets can use multiple if not all of them.

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#93

Post by jcims »

topspin wrote: post #52
gh02t wrote: post #24

Earlier quoted context omitted.

The signal GPS uses is actually very very weak and can be jammed pretty easily just by spewing a bunch of noise in the general area of the spectrum where it lies. Military grade receivers have some countermeasures that civilian equipment doesn't (e.g. the military signals have much wider bandwidth to work with, and you can also do some antenna magic), but jamming is still a problem for them too and it's a pretty acti…

"and you can also do some antenna magic" Just thinking about what that would involve. Very high gain antennas could track individual GPS satellites and probably defeat jammers. A phased array system (similar to Starlink's 'dishy', but probably larger due to the much lower frequency) might also work. Either solution would make many if not most uses of GPS either physically impractical and/or too costly.

Speaking of Starlink, there was a news story posted here not too long ago about using Starlink satellite signals to determine location (within 8 meters IIRC)

https://news.ycombinator.com/item?id=28656566

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#94

Post by Dylan16807 »

topspin wrote: post #85
oceanplexian wrote: post #84

Earlier quoted context omitted.

You can defeat jamming in a fairly unsophisticated way by using an antenna that can only receive signals from a specific direction (i.e straight up), while everything else is filtered out. If the jammer is to the side or below you it wouldn’t do much good. The problem is for GPS to work you need to be able to see a few of the sats and some will be closer to the horizon.

"antenna that can only receive signals from a specific direction" That's what "high gain" means; the main lobe is strongly focused in some direction. Actively tracking multiple moving satellites makes this approach mostly unworkable.

You were specifically talking about "very high gain" to track individual satellites.

Having a 60-120 degree cone pointed straight up is a different category of solution entirely.

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#95

Post by sandworm101 »

ryandrake wrote: post #36

> "Aircraft are greatly affected by the GPS jamming and it's not taken seriously by management," reads one report. "We've been told we can't ask to stop jamming, and to just put everyone on headings." This is the military practicing, but I would hope that civilian airline transport operations are also robust to GNSS unavailability or denial. Even private pilots in little Cessnas are taught to navigate using radio-nav…

>> a single point of failure, is pretty concerning.

If is it concerning, we must have a definition of "failure". Does failure mean the inability to fly a route as planned? If so then we cannot fly any routes via GPS that we cannot fly without GPS. So GPS doesn't really add any efficiencies. But if we instead define failure as "danger to life" then we can accept that when GPS fails we will use the other systems to get aircraft to a safe landing, even if flights don't complete as planned. Under that definition we can still enjoy the efficiencies of GPS without maintaining a backup that can instantly replace all GPS functions.

This is very important in a military context too. If you always need a 100% backup at the ready then you cannot ever use a novel system. Any new system won't have a backup that is 100% equal. So to leverage new tech you must accept the risk that you may loose some abilities should it fail. If you won't use the new toy until it has a 100% backup, you will end up never playing with any new toys/weapons.

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#96

Post by SavantIdiot »

pigbearpig wrote: post #51
andrepew wrote: post #19

Can someone more familiar with the situation explain why they jam GPS at all? You'd think the vast industry around the military could replace actual jamming with training aids. Even if the bespoke training tools are expensive, I doubt they're as expensive as an airliner wandering in to an active missile range. Not to mention the economic disruption to air traffic throughput.

Probably the same reason Netflix used/uses Chaos Monkey to actually cause problems, rather than just relying on training aids. You need to find the problems you didn't anticipate.

I spent years working on CPU validation. One classic method is random template based injection. You do three setup things: 1) pick a bunch of registers and busses that you will toggle to 1/0 in the RTL, 2) then code a bunch of mutexes of things that absolutely cannot happen (e.g., and AND cannot act like an XOR), 3) and then write checkers that look for bad conditions that should not happen. Then you press go literally run "coverage" by generating trillions of random test patterns and see if they toggle checker failures. There are behavioral tricks to reduce the search space (hierarchy helps), but it is one classic method. It can only be done a few times, so you really have to nail down your revision before you each up weeks of compute time on thousands of servers running random noise!

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#97

Post by GCU-Empiricist »

andrepew wrote: post #19

Can someone more familiar with the situation explain why they jam GPS at all? You'd think the vast industry around the military could replace actual jamming with training aids. Even if the bespoke training tools are expensive, I doubt they're as expensive as an airliner wandering in to an active missile range. Not to mention the economic disruption to air traffic throughput.

SO the US military is heavily reliant on GPS, and they know it, and so do professionals on the other side. There is a lot of good reason to think that if the US gets into a Large State action, which is relatively unlikely but. . . , then the opposition will employ GPS jamming to negate some of the more smart and collateral damage avoiding systems. I've been out for almost a decade, so I don't know if secondary powers have reliable and ubiquitous GPS jamming capabilities, but I'd bet dollars to donuts IRAN has spent significant funding to acquire GPS jamming. All of this gives a a context for why the military both uses training aids (marker blackout over GPS, manually disabled data links, and whatever more high tech the have devised) and real operate in jamming training, possibly as final training, certification training/exams, if my experience in sibling forces is any guide.

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#98

Post by KennyBlanken »

pmorici wrote: post #92
Crosseye_Jack wrote: post #71

Earlier quoted context omitted.

Didn't they actually remove selective availability from the new sat's that were launched. https://web.archive.org/web/20080113123316/http://pnt.gov/pu... > In September 2007, the U.S. Government announced its decision to procure the future generation of GPS satellites, known as GPS III, without the SA feature. Doing this will make the policy decision of 2000 permanent and eliminate a source of uncertainty in GPS perf…

I think it is a moot point because there are 5 position constellations now days (US, EU, China, Russia, Japan) and many popular consumer chipsets can use multiple if not all of them.

It's not moot for aviation, where GPS units can be decades old, in part due to how expensive avionics are due to an absolutely mind-boggling amount of FAA regulations.

The FAA is a giant lumbering dinosaur that spends a lot of time making sure private pilots generate huge reams of paperwork and restricting the kinds of equipment that can go into various categories of planes, when the overwhelming majority of GA crashes are 1)controlled flight into terrain and 2)running out of fuel.

We'd have a lot less controlled flight into terrain if the FAA would unclench its avionics regulations asshole. Thankfully anyone can run an iPad with Foreflight, or any number of iOS and Android apps, that provide rudimentary terrain awareness and backup navigation.

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#99

Post by CalChris »

This is jamming and not GPS spoofing. Wouldn't the navigation system 'fail' and that pilot switch over to flying by heading? I would think the civilian craft would have to be robust in the presence of spoofing (military testing). ATC would declare a certain area as GPS off, a NOTAM or something.

Re: FAA Fumbled Its Response to a Surge in GPS Jamming

#100

Post by RNCTX »

anyfoo wrote: post #54
ryandrake wrote: post #36

> "Aircraft are greatly affected by the GPS jamming and it's not taken seriously by management," reads one report. "We've been told we can't ask to stop jamming, and to just put everyone on headings." This is the military practicing, but I would hope that civilian airline transport operations are also robust to GNSS unavailability or denial. Even private pilots in little Cessnas are taught to navigate using radio-nav…

Are they still taught to do NDB approaches? I thought that's been phased out, too. In fact I was told the other day that the US officially tuned off the NDBs? Does not apply to VORs then, but as you say, the fact that they get phased out more and more is concerning.

There are no more usable NDBs in/around most bravo cities. The last one in DFW was decommissioned about 3 years ago. Any other ones that are still functional are on borrowed time.

Furthermore, no one is making the receivers anymore. If you have an NDB needle in the panel you are flying an airplane with some awfully old gauges....

Post reply on HN