GPS Jamming Exercise

[Redneck_pilot86]

Interesting NOTAM:

161274 CZEG EDMONTON FIR
CZEG DUE TO GPS JAMMING EXER, GPS (INCLUDING WAAS,
GBAS(GROUND BASED AUGMENTATION SYSTEM), AND ADS-B)
INTERMITTENT LOSS OF SIGNAL MAY BE EXPERIENCED WITHIN RADIUS
402NM CENTRE 651819N 1445614W (APRX 168 NM WNW CYDA AD)
FL400 TO UNL, DECREASING IN AREA WITH A DECREASE IN
ALT DEFINED AS:
396 NM RADIUS AT FL250
386 NM RADIUS AT 10000 FT AGL
252 NM RADIUS AT 4000 FT AGL
209 NM RADIUS AT 50 FT AGL
GPS BASED OPS AND RNAV GNSS APCH MAY BE AFFECTED AT THE
FOLLOWING AD: WHITEHORSE(CYXY),INUVIK(CYEV), OLD CROW(CYOC),
FT.MCPHERSON(CZFM), DAWSON CITY(CYDA), FARO(CZFA), FORT GOOD
HOPE(CYGH), AKLAVIK(CYKD). INFORM ATC IF LOSS OF GPS SIGNALS
AFFECTS ABILITY TO NAVIGATE.
AUG 08 2240-2359
AUG 09-12 0000-0210, 1630-2000, 2240-2359
AUG 15-18 0000-0210, 1630-2000, 2240-2359
AUG 19 0000-0210, 1630-2000
1608082240 TIL 1608192000

[Meatservo]

Boy. anyone who learned to fly after 1995 or so must be shaking in their boots.

[xchox]

Boy. anyone who learned to fly after 1995 or so must be shaking in their boots.

Even those after who have just grown accustomed to the luxury of GPS. lol

[goingnowherefast]

We'll see if people still know how to fly with NDBs

[lazyeight]

Boy. anyone who learned to fly after 1995 or so must be shaking in their boots.

Learned to fly well after that and full capable of flying ILS, NDB, and VOR approaches. Some school still teach it, and the jobs I've had needed it as well.

[Cessna 180]

Another issue is a lot of operators have eliminated DME as GPS is a substitute. Makes you question the removal of VOR airways in Southern Ontario and parts of the US. The US government routinely jams GPS in the Western USA. Lots of GA planes and operators no longer have ADFs installed to add to that.

[mantogasrsrwy]

.

[Meatservo]

.

I agree with mantogasrsrwy. He brings up an excellent point.

[Hockaloogie]

I agree with mantogasrsrwy. He brings up an excellent point.

[mantogasrsrwy]

..

[niss]

..

Don't beat yourself up too badly. In that situation who could blame you for shitting your pants? I mean that probably ruined your daughters recital, but it happens.

[goingnowherefast]

Satellite based navigation is the future. NDBs are 1920s technology; and without a GPS, require a archaic procedure turn! Extremely wasteful. "Don't worry guys, we have to fly 10 miles away from the airport before we can turn around and land.

I can't wait until the day when we, in Canada, have a GPS receiver and a Galileo receiver in the aircraft. It's already happening in Europe http://www.gsa.europa.eu/segment/aviation. They can jam GPS all they want, but Europe has the Galileo system, Russia has GLONASS and China is developing BeiDou. Multiple, redundant satellite navigation infrastructures.

Like it or not, the NDB, VOR, DME are all eventually going to join the LORAN C and Radio Range. The ILS will take a while to die as it still allows more precision for CAT II and CAT III approaches.

Unfortunately the world isn't there yet, and we are often stuck depending on near 100 year old technology as a backup to WAAS capable GPS.

[Hockaloogie]

..

That's beside the point.

[mantogasrsrwy]

[Gannet167]

Every piece of kit has it's vulnerabilities. Everyone jokes about the fragility of GPS nav, and how if the Americans wanted to, they could shut everyone down. Better to rely on the NDB - the tried, tested and true "old school" methods that aren't part of these new age fads. Children of the Magenta, and all that. But if you turn the power off, conventional navaids are also worthless. They can also be jammed or interfered with to prevent effective navigation. No one seems to notice when and NDB or VOR is notam'ed u/s, or unmonitored. I'm sure there were similar arguments when VORs and TACANs were invented, by the old timers using radio range.

[Mr. North]

Every form of navigation has it's vulnerabilities. GPS navigation is especially vulnerable on account of it's incredibly weak signal.

The signals are weak. Mr Curry likens them to a 20-watt light bulb viewed from 12,000 miles (19,300 km). And the jammers are cheap: a driver can buy a dashboard model for about £50 ($78). They are a growing menace. The bubbles of electromagnetic noise they create interfere with legitimate GPS users. They can disrupt civil aviation and kill mobile-phone signals, too.

http://www.economist.com/news/internati ... isrupt-out

To be honest, living in the age of laser strikes and drones, I'm surprised there isn't more GPS jamming going on. Anyone can easily buy a jammer. And it would only take a few, positioned around an airport, to make the area unreliable.

http://www.thesignaljammer.com/categories/GPS-Jammers/

[AuxBatOn]

The GPS signal uses Spread Spectrum techniques which makes it easier to pull it out of the noise. You'd be surprised how much jamming is required to disrupt the signal to the point it is unusable.

[niss]

The GPS signal uses Spread Spectrum techniques which makes it easier to pull it out of the noise. You'd be surprised how much jamming is required to disrupt the signal to the point it is unusable.

I imagine it's somewhat of a secret, but can you give any idea as to how the aircraft performing EW are protected from jamming? Is the jamming signal directed away from the equipment in the a/c or is there something more complicated going on?

[Flybabe]

Jamming affects my Phenom 300 to the point that it knocks off our autopilot and yaw damper. Procedure is to slow to mach .63 (or less) and descend.

Personally got hit with it once in the US. We now make every attempt to avoid the areas affected, if possible.

[photofly]

The GPS signal uses Spread Spectrum techniques which makes it easier to pull it out of the noise. You'd be surprised how much jamming is required to disrupt the signal to the point it is unusable.

GPS doesn't use spread spectrum techniques. Unlike the Russian and European systems, GPS uses only two precise fixed frequencies with a different signal transmitted simultaneously on each. You may be thinking of Gold codes, which GPS does use extensively.

[cgzro]

Minor quibble - I believe GPS uses DSSS or Direct-Sequence-Spread-Spectrum so technically it is spread spectrum but its not spreading it over a very wide band (you phase shift the carrier by the PN sequence), unlike frequency hopping which can spread over a wide range and even leave gaps all over the place (because it retunes the carrier instead of simply shifting it a bit). DSSS is I suppose pretty easy to jam despite it using a form of spread spectrum because its narrow and continuous within that spectrum, while frequency hopping spread spectrum is hard to jam because its all over the damn place and you can't easily jam all of the possible bands and everything in between.

A Gold code is just a property of a code sequence in a set of code sequence such that they have a low probability of being correlated anywhere with each other and so it could be used to drive either direct or frequency hopping spread spectrum.

Anyway having multiple systems Russian, American, European, Chinese and receivers that can decode all of them would seem like a wise thing to have but no doubt the American military will jam all of them at the same time as receivers that work on all 4 systems at the same time become more prevalent.

Perhaps its back to INS which should be pretty darn good with the ultra light weight accelerometers etc that we have now. Use GPS and INS and if the GPS position drops out you just integrate your way through the outage.

[fish4life]

Perhaps the GPS Auxbat uses is much broader ranged / harder to jam than our civilian ones?

[cgzro]

From what I can see the military and civilian versions both spread the very slow individual satellite signals over 20Mhz worth of spectrum. One is centred at 1.5Ghz and the other is centred about 1.2Ghz. The military one is encrypted and uses different pseudo random codes so no idea what the impact is on jam ability etc. but they both seem to use the same amount of spectrum to spread over and do not hop about leaving holes as with frequency hopping spread spectrum.

[CID]

GPS is almost ridiculously easily to jam over large areas deliberately if you know what you're doing. It's very difficult to disrupt GPS navigation if you aren't trying to do it deliberately.

[CID]

Satellite based navigation is the future. NDBs are 1920s technology; and without a GPS, require a archaic procedure turn! Extremely wasteful. "Don't worry guys, we have to fly 10 miles away from the airport before we can turn around and land.

I can't wait until the day when we, in Canada, have a GPS receiver and a Galileo receiver in the aircraft. It's already happening in Europe http://www.gsa.europa.eu/segment/aviation. They can jam GPS all they want, but Europe has the Galileo system, Russia has GLONASS and China is developing BeiDou. Multiple, redundant satellite navigation infrastructures.

Like it or not, the NDB, VOR, DME are all eventually going to join the LORAN C and Radio Range. The ILS will take a while to die as it still allows more precision for CAT II and CAT III approaches.

Unfortunately the world isn't there yet, and we are often stuck depending on near 100 year old technology as a backup to WAAS capable GPS.

You're talking out your ass a little here. With respect to jamming, redundancy doesn't help. These signals are usually jammed locally by transmitting high power signals on the system frequency. This raises the noise floor so that all the intelligence buried in the "noise" is essentially obliterated.

As for ADF/VOR/ILS/DME being 100 years old, you're off the mark. It's like saying airplanes are 100 year old technology in a way although you'd at least be closer to reality there.

Bill Lear developed the ADF in 1940. It took awhile for it to become a common aircraft navigation aid. VOR stations were developed at about the same time and ILS took a bit longer to deploy with only 6 airports with ILS in the US by the mid 40s. It took until the mid 60s before a fully automated ILS landing was achieved.

In the 50s, DME (an Australian invention) appeared on the scene and helped to enhance ILS capabilities. rho/theta area navigation didn't happen until the late 70s when portable computing power technology caught up.

And fast forward to today where contrary to what you suppose (ILS backing up WAAS GPS) there is still no widely used replacement for ILS. WAAS fell short and LAAS is trying hard but GLS approaches are still behind ILS capabilities.

As for those archaic procedure turns, in the airline world you are largely either tied to departure/arrival procedures and/or vectored in. The days of flying 10 miles out to intercept an ILS are simply not over.