GPS jamming in Flordia

[Chotu]

Originally Posted by redneckrob

I'm curious as to your source of this bit of information? Have you tried for decades to find the UN complex by boat but been foiled each time by "jamming"? That only impacts the approaches by water? And where, exactly does this happen? I have a good friend who is CO of CG Sector NY who would really want to know about this if it was true, although almost inconceivable that CG small boats going by there multiple times a day for decades wouldn't have experienced this if it was a real thing.
Now that I think about it, I've actually also flown by there a number of times in a helicopter over the water, a couple times below 100' (benefit that comes with flying a big orange CG helo) and never gotten an alert, which we would have had it had been "jammed". I actually have more than a passing interest in GPS, is was my area of focus in my undergrad EE program to the point I actually built a GPS receiver from scratch. Also did a lot of anechoic chamber work on propagation and antennas. Given what I know about GPS and what I've experienced at that specific location again I'm gonna have to say that's simply a fabrication, sorry to ruin a story based on that one time your GPS stopped working that I'm sure gets better milage with a less credulous and more conspiracy minded audience.

Source?? Are you joking?

It comes from decades of transiting the East River on my boats. Every single time you get really close to the UN, the signal is jammed. No position data.

I'm going to say you have absolutely no ideas what you're talking about because you have not ONCE even been there by boat while I've transited it many dozens of times.

What an absolutely odd thing to be starting some kind of internet fight about.

You built a GPS receiver? WOW. I'm soooo impressed. I built the entire communication system for the FAST, ACE and Cluster series of SMEX explorers at NASA. But you don't see me acting like an idiot about it on here to pretend I know someone else's home cruising area better than they do.

[Hardhead]

okay fellows - I say you are both right in your own way. I'd bet you can't pinpoint the UN building, but can still get close enough to see it. Then again, all I know about GPS is hoping it works...

[Cadence]

I believe it's over blown. If not, drag out the charts and compass if you don't have them what the hell are you doing in the water.

[redneckrob]

Originally Posted by Chotu

Source?? Are you joking?

It comes from decades of transiting the East River on my boats. Every single time you get really close to the UN, the signal is jammed. No position data.

I'm going to say you have absolutely no ideas what you're talking about because you have not ONCE even been there by boat while I've transited it many dozens of times.

What an absolutely odd thing to be starting some kind of internet fight about.

You built a GPS receiver? WOW. I'm soooo impressed. I built the entire communication system for the FAST, ACE and Cluster series of SMEX explorers at NASA. But you don't see me acting like an idiot about it on here to pretend I know someone else's home cruising area better than they do.

Then you'd certainly know that losing a position fix isn't the same thing as "jamming". It's patently absurd, both from a technical and practical standpoint, that "they" would put some kind of highly directional "jammer" in place that only impacted those on the surface (but not 100' above the surface) and only on the water, and only immediately next to the UN complex. It's also absurd that the CG small boats transiting that same bit of river literally multiple times a day don't experience this supposed "jamming", or that we'd allow that known hazard to navigation to exist without disclosure. So no, it's not an "odd thing to start an internet fight over", it's something that if real reflects what we would consider a huge failure of our NTM system as well as callous disregard for our professional responsibilities in the Coast Guard if it was known and covered up or ignored. Certainly, as I mentioned, something I don't see my friend and the entire line of Sector COs and everyone else who would have had to be aware of this over decades as ignoring or covering up. It's not your world so you might be more cavalier about it, but for those who maintain the nation's maritime navigation system for a living including the NTM system it's a serious responsibility and a pretty serious accusation that they'd know about GPS "jamming" that specifically impacted the waterway and ignore it.

Who knows why you lose the signal there in your boat. Maybe you've got an older single channel receiver an it just loses satellites from geometry and tall buildings, maybe it seems to happen more than it actually does, maybe it's just got a fault that lets some interference in from some other licensed transmitter operating around 1575 MHz or a harmonic of that. Lots of things make more sense then some crazy water side surface only narrow band "jamming" that isn't experienced by the maritime professionals using that waterway every day.

[Capt Gill]

When you make a statement such as yours I'm somewhat surprized of your reaction to the grilling you're getting. What did you expect, unquestioning agreement? You state, "Every single time you get really close to the UN, the signal is jammed. No position data." and "decades of transiting the East River on my boats" "I've transited it many dozens of times." These are pretty bold statements. Rather than backing them up by stating your authority via your credentials how about gathering some corroborating evidence, I'm sure there must be other boaters in the area using GPS?

[zemurray]

Originally Posted by Cadence

I believe it's over blown. If not, drag out the charts and compass if you don't have them what the hell are you doing in the water.

And your Sextant to get a position fix?

I was curious about this announcement too. What happens to the sailor who’s out at sea when the military does this? Maybe I should get that sextant and learn how to use it?

[delmarrey]

Originally Posted by zemurray

And your Sextant to get a position fix?

I was curious about this announcement too. What happens to the sailor who’s out at sea when the military does this? Maybe I should get that sextant and learn how to use it?

That’s what charts, dead reckoning and tri coordinates were for, before electronics. Other then visuals.

[Brewgyver]

Apparently, a fair number of truckers and other commercial drivers use GPS jammers to defeat tracking devices installed by the vehicle owners. There have been a number of issues in the Newark Airport area caused by such usage.

However, given that the FDR Parkway runs down the water side of the UN building, with no commercial traffic at all, this wouldn't seem likely to affect boats on the East River.

[Cpt Pat]

Originally Posted by S/V Adeline

I just viewed a YouTube video explaining GPS+, which apparently if a device has this feature it can pick up U.S. and Russian GPS satellites.

"GPS+" sounds like a marketing pitch. The correct term would be GNSS. I've been using GPS and GLONASS together for years now. The Galileo (European) constellation has also just entered production service. To take advantage of all three constellations, I'll be installing this product soon: https://digitalyachtamerica.com/product/gps160-nmea0183/. I'm installing it in a place where I can flip the DIP switches to disable an affected GNSS constellation. I am also using combined GPS and GLONASS for my AIS position data. AIS is worthless without valid position data. And combining GNSS sources yields a more accurate position solution (provided all the sources are healthy). My Class A AIS transponder requires two GNSS sources from two receivers. One receiver is GPS only, the other is GPS and GLONASS combined. If either GPS or GNSS goes bad, I get a "position disagreement" alarm. It has happened when the Russians had one bad satellite. That's immediate verification that something's wrong with either constellation.

BTW, those who poo-pooed my assertion here years ago that GPS was vulnerable to jamming, well, told you so! In an actual conflict, a determined adversary will probably jam all three constellations. So -- I still have my sextant aboard.

There's a reason the US Navy has resumed teaching celestial navigation...


(Source of picture below: US Coast Guard AIS Vessel Verification Service: https://www.navcen.uscg.gov/aisSearch/dbo_aisVessels_search.php)

[Montanan]

The Federal Aviation Authority (FAA) says that some GPS signals in Florida over the next few days will be jammed during military training exercises.

The jamming of signals is expected to last several hours on the designated exercise days.


"GPS testing is scheduled as follows and may result in unreliable or unavailable GPS signal," the FAA said in a flight advisory.

According to an FAA map, navigation from as low as 50 feet above ground up to Flight Level 400 (around 40,000 feet) could be affected. Reference map below depicting the altitude and radius of potential signal jamming. Should not be of issue for terrestrial or marine navigation.

Pilots are encouraged to report anomalies in accordance with the Aeronautical Information Manual paragraphs 1-1-13 and 5-3-3.

The military exercises are scheduled for the following days and times:

Saturday, Jan. 18, 2020 from 12 p.m. to 7 p.m.
Thursday, Jan. 23 from 7 a.m. to 7 p.m.
Friday, Jan. 24 from 6:30 a.m. to 7 p.m.

According to the Miami Herald, the FAA has not commented on how or if this will affect motorists or hikers using GPS on the ground. However, WINK News reports that the exercises should not affect the navigation systems in your cars or the maps on your cellphones.

Be mindful during the scheduled times just in case.

[S/V Adeline]

Originally Posted by Brewgyver

Apparently, a fair number of truckers and other commercial drivers use GPS jammers to defeat tracking devices installed by the vehicle owners. There have been a number of issues in the Newark Airport area caused by such usage.

However, given that the FDR Parkway runs down the water side of the UN building, with no commercial traffic at all, this wouldn't seem likely to affect boats on the East River.

A 5gal metal pail inverted over the *antenna* case would completely block the signal when I was OTR. (02-14) A bucket full of water setting above the case would report 100's of miles off. We had one truck show some 20 miles off the east coast of Florida for about 5 minutes with that trick.
They must have improved those systems a good deal if jammers are required now.
*Unless* they are installing a secondary GPS transmitter independent of the communications system.

[Hardhead]

Originally Posted by zemurray

And your Sextant to get a position fix?

I was curious about this announcement too. What happens to the sailor who’s out at sea when the military does this? Maybe I should get that sextant and learn how to use it?

I think that's a solid idea. We've all become so reliant on GPS - for a lot of people there's no real plan B for offshore navigation. Given how easy it appears to be to jam and goof with GPS signals - it might be something ner'dowells can be doing more easily in the future.

[zemurray]

Originally Posted by delmarrey

That’s what charts, dead reckoning and tri coordinates were for, before electronics. Other then visuals.

I understand that part, but I dont think you can reliably get a position when you dont have a visual reference using dead reckoning, without a sextant?

Originally Posted by Hardhead

I think that's a solid idea. We've all become so reliant on GPS - for a lot of people there's no real plan B for offshore navigation. Given how easy it appears to be to jam and goof with GPS signals - it might be something ner'dowells can be doing more easily in the future.

Yeah, it’s something I’ve definitely thought about. After the melt down when I escape on my boat, I’ll need a sextant. Especially after the Chinese knock all of our satellites out of the sky.

[Cpt Pat]

Originally Posted by Hardhead

I think that's a solid idea. We've all become so reliant on GPS - for a lot of people there's no real plan B for offshore navigation. Given how easy it appears to be to jam and goof with GPS signals - it might be something ner'dowells can be doing more easily in the future.

There is a Plan B solution: eLORAN. https://www.aviationtoday.com/2012/04/12/gps-backup-is-eloran-the-answer/

But our wonderful leaders in D.C. won't get off their duffs to implement it.

Till then, I'll keep practicing with my sextant, and repeating the old adage: "Never be far from a good D.R." (dead reckoned position) ... marked on a paper chart.


Having a backup to GNSS is really a matter of national security. Can you imagine the consequences of a large scale GNSS outage? 90% of the goods we consume come in by ship. And then there's the mess it would cause with air traffic.


By the way, has anyone wondered why North Korea hasn't bothered to equip their missiles with heat shields for re-entry? Maybe because they intend to detonate them above the atmosphere? Just saying...

[redneckrob]

Originally Posted by Hardhead

I think that's a solid idea. We've all become so reliant on GPS - for a lot of people there's no real plan B for offshore navigation. Given how easy it appears to be to jam and goof with GPS signals - it might be something ner'dowells can be doing more easily in the future.

The question is how much to actually need to know your position to the nearest couple feet when navigating a sub 10' draft vessel at 6 knots offshore? I could be pretty much anywhere in the world, lose all electronic nav, and still safely find the nearest continent at which point I could sail either direction safely offshore until I found a landfall lighthouse and from there safely navigate to a harbor. Sure there are a couple of atolls in the Pacific I could be really unlucky to run over at night (solution, don't sail at night) and if I'm really unlucky some unmarked offshore reefs, but in reality I'd feel pretty safe about the whole thing. I couldn't hit Charleston with any degree of accuracy coming from Burmuda, for example, but I sure could be confident of finding the East Coast of North America between NY and FL, and I'm sure you and the rest of our cruising compatriots could as well.

Not to mention the more realistic scenario where I just heave to until they come back online, which will happen in a few hours or days absent a world war at which point loss of electronic nav is the least of my concern and my savvy in celestial nav won't be worth a lot. And this is coming from someone who does actually know celestial nav. I just relearned it because it's a neat skill that I enjoyed, not because I've got some prepper idea that it's going to save me while the lemmings all fall off the failed GPS cliff. I think all of us who have any basic seamanship competence will be just fine in the event of an outage.