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Author Topic: scheduled GPS interference testing  (Read 877 times)

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hotrod180

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scheduled GPS interference testing
« on: April 04, 2017, 11:33:10 AM »
Got an email from the operators of my airport yesterday, advising of some scheduled GPS interference testing coming up soon.
Here's a link to the NOTAM:

https://www.faasafety.gov/files/notices/2017/Apr/FFC_17-01_GPS_Flight_Advisory.pdf

Essentially, expect GPS disruptions in an area centered on Bangor Submarine Base near Bremerton WA.
Multiple dates starting April 6 and on through May 6.
Dates & time subject to change, NOTAM(s) will be updated / issued as required.

hotrod180

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Re: scheduled GPS interference testing
« Reply #1 on: April 15, 2017, 09:06:21 PM »
Curious if anyone has experienced any GPS weirdness?

Domenick

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Re: scheduled GPS interference testing
« Reply #2 on: April 16, 2017, 07:20:03 AM »
Can anyone speculate on the reason for these GPS interference warnings? They are not unique to Bangor. They occur all over the country, particularly in the west. Since GPS is very easy to jam, not convinced the interference is jammer testing, but must be some sort electromagnetic interference.

For example:
http://gizmodo.com/faa-warns-of-gps-outages-this-month-during-mysterious-t-1780866590
« Last Edit: April 16, 2017, 07:22:12 AM by Domenick »
Domenick
PA-28-161
Snohomish, WA, Harvey Field, S43

hotrod180

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Re: scheduled GPS interference testing
« Reply #3 on: April 16, 2017, 09:03:08 AM »
Maybe testing the capability to burn through said jamming?

tosten

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Re: scheduled GPS interference testing
« Reply #4 on: April 16, 2017, 09:48:41 PM »
Maybe testing the capability to burn through said jamming?


Why jam?  DOD runs it, just turn off if sinister uses suspected.
Paul

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Cabbage

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Re: scheduled GPS interference testing
« Reply #5 on: April 17, 2017, 07:47:39 AM »
I suspect it has to do with the ability to jam the GPS signal on purpose.  We are not the only country using GPS for guidance.  If we were at war and some other country was attacking us with munitions that were guided by GPS, the ability to jam the signal might make the difference between a direct hit and one that misses by just enough for the target to survive.

trucktent

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Re: scheduled GPS interference testing
« Reply #6 on: April 17, 2017, 08:39:12 AM »
Maybe testing the capability to burn through said jamming?


Why jam?  DOD runs it, just turn off if sinister uses suspected.

Jam, turn off, interfere with. How is this ever a good idea? Anyone out there shooting IFR approaches that might appreciate if your GPS is within 1000' accuracy? Let alone within 30' Pick one, vertical or horizontal.

Hope those oil tankers can stay in the shipping lanes and avoid the rocks too.

I had some weird GPS issues off of McNeal Island at night last fall. The magenta line on foreflight showed a north track. For about 5 minutes the GPS signal would have had me flying east instead of north. Foreflight was showing a green GPS signal box.  If I couldn't see my destination I would have been easily misdirected into SeaTac airspace.



James
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KBFI - Seattle, WA

Les

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Re: scheduled GPS interference testing
« Reply #7 on: April 17, 2017, 09:26:14 AM »
Here is a blog article discussing this. 

BLUF - nobody really knows.

http://gizmodo.com/faa-warns-of-gps-outages-this-month-during-mysterious-t-1780866590
- Les
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http://www.lesflue.com

hotrod180

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Re: scheduled GPS interference testing
« Reply #8 on: April 17, 2017, 09:55:43 AM »
.....Why jam?  DOD runs it, just turn off if sinister uses suspected. 

Cause maybe while "they" are using it to target us, we're using it to target them.

bitten192

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Re: scheduled GPS interference testing
« Reply #9 on: April 20, 2017, 02:21:06 PM »
They do it a lot near Fallon NAS (Reno) too.

Cabbage

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Re: scheduled GPS interference testing
« Reply #10 on: April 21, 2017, 06:36:45 AM »
For what it's worth, I was up at BLI about a week ago.  When I taxied out to leave, my GPS went from the map page to the home page on its own.  I put it back on map. It went back to home.  I did this several times before I got to the end of the runway.  Being VFR I didn't really care.  Once airborne, it all worked normally and has ever since.  Seemed kind of odd, but I wonder if the EFA-18's were messing with me.

groupw

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Re: scheduled GPS interference testing
« Reply #11 on: May 15, 2017, 05:21:49 PM »
At a place like the ground at BFI, there are plenty of very strong interfering signals. No matter how good a receiver is, it can be overwhelmed if the interference is strong enough. My guess is that was the reason for the GPS malfunction at that location.

Roy

hotrod180

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Re: scheduled GPS interference testing
« Reply #12 on: September 13, 2017, 09:25:05 AM »
More GPS testing near Bangor Sub Base:
(thanks to KPWT Airpot Mgr Tim Mensonides for sending out this email alert)

Please see below regarding GPS Interference Testing taking place in the Bremerton Area:
 
FLIGHT ADVISORY - GPS Interference Testing - Bremerton, WA
Notice Number: NOTC7359
FLIGHT ADVISORY - GPS Interference Testing
FFC GPS 17-07 (FLEET FORCE COMMAND)
11 September – 14 October 2017
Bremerton, WA
Centered at 474356N1224354W or the SEA301025
The entire flight advisory may be accessed and downloaded at the following address:
https://www.faasafety.gov/…/FFC_17-07_GPS_Flight_Advisory.p…
Pilots are advised to check NOTAMs frequently for possible changes prior to operations in the area.
NOTAMs will be published at least 24 hours in advance of any GPS tests.
 
Blue Skies,

Tim Mensonides, C.M.
Airport Manager
Bremerton National Airport

Domenick

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Re: scheduled GPS interference testing
« Reply #13 on: October 14, 2017, 08:47:05 AM »
Another GPS Advisory:

FLIGHT ADVISORY GPS INTERFERENCE TESTING October 16 – November 18, 2017 Bremerton, WA.
Notice Number: NOTC7431

FLIGHT ADVISORY
GPS INTERFERENCE TESTING
FFC GPS 17-09 (FLEET FORCE COMMAND)
October 16 – November 18, 2017
Bremerton, WA.
Additional information:
https://www.faasafety.gov/files/notices/2017/Oct/FFC_17-09_GPS_Flight_Advisory.pdf
Domenick
PA-28-161
Snohomish, WA, Harvey Field, S43

groupw

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Re: scheduled GPS interference testing
« Reply #14 on: October 14, 2017, 11:06:44 AM »
Thanks for the heads-up. These are huge areas.

Although most people talk about "jamming", the GPS community distinguishes between "jamming" and "spoofing". The former is an attempt to make GPS unusable. The latter can be more serious, since it means altering or producing GPS signals that seem ok but cause receivers to show an incorrect position. I know there's a lot of work going on to try and increase immunity of receivers and the GPS system to both these threats.

Roy