Here we go again with GPS interference testing...

chemgeek

chemgeek

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This time 9 full days of GPS interference testing at Fort Drum which will wipe out all of the approaches at our airport and many others in Central New York. With MON coming and the scheduled decommissioning of most of this area's VORs imminent, even enroute IFR nav becomes more difficult. Of course ADS-B position reporting gets wiped, too. I guess we still need radar coverage, eh?

I understand the need for the military to do their thing, but 9 days?? Its crippling to have a GPS centric airspace system if we regionally disable it for days at a time. If planes can't fly into our airport because of unavailable IFR approaches, it has significant economic impacts. Seems like an issue AOPA should be interested in? Its not just Central NY: the SW has suffered for a long time, and recently there have been large testing regions centered offshore in the SE. I suppose testing doesn't go on continuously, but you don't know when it is.
 
That's the unfortunate side effect of the fact that the military owns/operates GPS. They get a lot of freedom to do as they want
 
They should do it waayyyy offshore. They also run the nuclear program too, but that doesn’t mean they can test wherever they want either... ;)
 
GA is an after thought ,the government considers it a minor inconvenience in the big picture.
 
dans2992 said:
They should do it waayyyy offshore. They also run the nuclear program too, but that doesn’t mean they can test wherever they want either... ;)
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A ton of stuff, not just aviation related, relies on GPS. I'm surprised the military hasn't been pushed to do their testing on the sea or isolate it to the various test ranges out west, where the impact would be substantially reduced. Kinda like sonic booms.
 
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kyleb said:
A ton of stuff, not just aviation related, relies on GPS. I'm surprised the military hasn't been pushed to do their testing on the sea or isolate it to the various test ranges out west, where the impact would be substantially reduced. Kinda like sonic booms.
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It seems that even with these NOTAMS, It’s rare to actually see GPS issues due to the testing.
 
kyleb said:
A ton of stuff, not just aviation related, relies on GPS. I'm surprised the military hasn't been pushed to do their testing on the sea or isolate it to the various test ranges out west, where the impact would be substantially reduced. Kinda like sonic booms.
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"out west"....Most of New Mexico, much of Colorado, a bit of Wyoning, a goodly chunk of west Texas, Arizona and southern California are identified on the GPS testing website - all the time. Just because we're in the timezone that everyone else forgets about, remember 1) we vote 2) we pay taxes 3) we fly GA 4) you're talking about (estimating areas just listed, based on https://www.worldatlas.com/articles/us-states-by-population.html)
southern California 20 Million
Arizona 7 M
Colorado 5 M
New Mexico 2 M
Texas 8 M
est total 42 Million

Take a look at the GPS map and understand that "various test ranges out west" are, at times, entire states, even multiple states. Most military GPS testing is to identify how to defend against GPS attacks. Difficult to do that at sea.

As for AOPA "Seems like an issue AOPA should be interested in?" No, contact your CongressCritters - that has more effect.

[time for tiny violins playing]

I'm so terribly sorry if GPS testing interrupts your life. Be happy you don't get this very often. It's day to day for us, and we still manage to survive.
 
I feel safer.

Legit I don’t get why they can’t do this stuff out in the ocean or in very remote places.
 
murphey said:
I'm so terribly sorry if GPS testing interrupts your life. Be happy you don't get this very often. It's day to day for us, and we still manage to survive.
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I would have been happier If the same government who now has to continually test and defend GPS against technology attacks hadn’t walked away from a valuable, tamper resistant, and non-space based LORAN asset!
 
ElPaso Pilot said:
I would have been happier If the same government who now has to continually test and defend GPS against technology attacks hadn’t walked away from a valuable, tamper resistant, and non-space based LORAN asset!
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In another thread, we were told that eLoran is here. Hopefully, Garmin will come out with receivers.
 
The Navy exercises are out at sea. Ft Drum is Army so obviously they have to do it over land.
 
Testing at sea? Good thought but also fraught with problems. Few thoughts:

1-The testing requires a lot of special equipment operated under tightly controlled conditions. Kind of hard to implement at sea.

2-DOD does not just decide let's go do these tests. There is a protocol involved requiring tons of review and approval by many other government agencies.

3-To avoid impacting US airspace entirely the tests would have to take place in international waters/air space. Can you imagine what a huge can of worms that review/approval process would be?

4-With the current approach should GPS service be disrupted at least there is traditional land based navaids to fall back on.
 
Try these things called a VOR. If you punch in some numbers on the other side of your com, turn the little squeaky dial thingie with the needle in the middle to the track you want to go and keep the needle in the middle, you should end up where the magenta line would have put you as well. It’s kinda like drinking a Coke from Mexico out of a recycled bottle or watching ME TV just for kicks.
 
Unit74 said:
Try these things called a VOR. If you punch in some numbers on the other side of your com, turn the little squeaky dial thingie with the needle in the middle to the track you want to go and keep the needle in the middle, you should end up where the magenta line would have put you as well. It’s kinda like drinking a Coke from Mexico out of a recycled bottle or watching ME TV just for kicks.
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Unfortunately, the "thing called a VOR" does not enable you to fly an approach into my airport, or many others. Our only VOR approach was NOTAMed out of service several years ago, and will be officially deleted September 12. No GPS means the ceiling has to be above MVA to make an IFR descent for the visual or you divert to an ILS or other ground-based approach. Many airports are now served only by GPS approaches.
 
I think there’s some misunderstanding here about what “GPS interference testing” means as it pertains in this instance. These aren’t some dudes in white coats doing a classified test that solely revolves around GPS nav. These are war gaming exercises and the GPS jamming aspect is only one part of it. Ive flown in several overseas. Basically OPFOR jam your stuff, the “observers” evaluate how well the GPS performs (vulnerability) during the event and how well the crew adapts (INS) to the LOS.

Just like this...and yes, they do it at sea in international waters all the time.

https://arstechnica.com/information...ise-ushers-in-gps-jamming-season-across-west/
 
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Velocity173 if you are still flying for DOD could you do some checking then give us a quick rundown on the approval process for this testing CONUS and OCONUS? Just a quick ROM thing. I am guessing for CONUS it is a pretty hefty burden. OCONUS probably borders on having teeth pulled or broken bones set without anesthesia.
 
jonvcaples said:
Velocity173 if you are still flying for DOD could you do some checking then give us a quick rundown on the approval process for this testing CONUS and OCONUS? Just a quick ROM thing. I am guessing for CONUS it is a pretty hefty burden. OCONUS probably borders on having teeth pulled or broken bones set without anesthesia.
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I don’t fly military anymore. My duties as a pilot were simply the basic tactics side of “actions on contact.” That means reacting to GPS / radio jamming, radar warning indications, MILES gear indications, etc. The planning aspect of a large scale military exercise are done by military staff personnel. Duties well above my pay grade but obviously entails extensive coordination between DOD and civilian agencies.
 
This guy says don't worry about it:

Juliet Hotel said:
Probability of that is more than zero but also significantly less than the probability of the single lycoming deciding to get quiet unexpectedly which is itself a very low probability. You can really chase your tail down some deep rabbit holes figuring out IFR equipment redundancies. It always seemed kind of silly to go so deep down some of those holes while skipping right over the single power plant hole.
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dans2992 said:
It seems that even with these NOTAMS, It’s rare to actually see GPS issues due to the testing.
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This is my understanding, too. Can anyone that is regularly impacted by one of these tests comment on actual loss of nav events in flight?
 
George Mohr said:
This is my understanding, too. Can anyone that is regularly impacted by one of these tests comment on actual loss of nav events in flight?
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Well, I flew about 25nm from one last week at FL310 where it was supposed to be affecting an area well over 200nm in radius and didn't have a single hiccup.

I did plan a backup route with VORs, though, and had to go and look up what the service volume of a high-altitude VOR was.
 
NOTAM'ed at PAX river pretty regularly, but haven't seen an impact.

GPS is an awful weak and vulnerable signal. Not much in $$$ or expertise needed to just jam it over a smallish area.
 
George Mohr said:
This is my understanding, too. Can anyone that is regularly impacted by one of these tests comment on actual loss of nav events in flight?
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Every week or so I lose one or both GPS receivers while flying through the area (ABQ and the area north of White Sands). Doesn’t really matter to an airliner since GPS is just one of many inputs to our nav systems, but yesterday a Citation ahead of us requested vectors from ATC while they figured what VORs they’d need to use.

It’s probably most disruptive to the poor Center controller that has to keep answering questions about it.
 
You'd think they would have a specific set of auxiliary channels or frequencies that they could use to perform these tests. When I was in the Civil Air Patrol we did searches with a practice ELT that broadcasted on 121.6 to not disturb guard. Must be a government operation...
 
kyleb said:
A ton of stuff, not just aviation related, relies on GPS. I'm surprised the military hasn't been pushed to do their testing on the sea or isolate it to the various test ranges out west, where the impact would be substantially reduced. Kinda like sonic booms.
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The radius of affect is very small at ground level.
 
That would be great but the existing technology doesn't make this possible. Kind of like in the old days of scanners...all you needed was a frequency but now with all the digital systems you need about 50 different pieces of information. One wrong setting and nothing works.
 
George Mohr said:
This is my understanding, too. Can anyone that is regularly impacted by one of these tests comment on actual loss of nav events in flight?
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Living north of the very frequent New Mexico testing area, and inside the big circle, I see more problems from steep turns blocking the signal to the GPS antenna on top of the airframe than the actual interference. Maybe Canada has the right idea for GPS antenna on top and bottom (diversity).
 
murphey said:
Maybe Canada has the right idea for GPS antenna on top and bottom (diversity).
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Lord don't give them ideas. ADSB-Out mandate is bad enough as it is. The one good thing we could have taken from the Canadians (owner maintained category) we straight up poison pilled with prejudice. Can't pick the right apple from the produce section if our life depended on it.
 
Handle the problem the american way. Get the affected users together, put money in pot, hire scumbag lawyer and sue.
 
Yes, there are impacts. Otherwise, there wouldn't be NOTAMs.

But the impacts are never as severe as the worst-case that the NOTAMs describe.

GPS outages are posted for Fort Polk, La evetns multiple times a year. I've flown many times within the NOTAM'd time/airspace, and have yet to see an effect. No need to get hysterical about these things.
 
James331 said:
Legit I don’t get why they can’t do this stuff out in the ocean or in very remote places.
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Or do it very late at night which is what I see most from White Sands restricted area, but not guaranteed to be at night.

And if I am VFR I can drop below the top of the maintain range and get the GPS signal back.


George Mohr said:
Can anyone that is regularly impacted by one of these tests comment on actual loss of nav events in flight?
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Yes. I ask ATC to tell them it is working.....
 
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