GPS Jamming
Apparently you are allowed to rely on GPS to stop you from going where you don't want to go (the Airspace Aware unit sponsored by NATS)
...but not to guide you where you do want to go.
All forms of navigation, including looking out of the window, fail from time to time. Pilots looking forward to a long and happy life do not rely on any one (except on a gin-clear day in familiar territory). Use GPS (most of us do), but keep a visual check on landmarks outside, or cross check with VOR/DME or whatever. Surely, assuming that something might fail is just good airmanship (and certainly part of IMC/IR training).
Join Date: Mar 2011
Location: Essex UK
Posts: 186
Likes: 0
Received 0 Likes
on
0 Posts
Jam is a bit misleading. The US DOD run the show. If they wished they could simply re-enable SA with whatever parameters they wish to interrfere with accuracy even to the extent of limiting the accuracy to certain altitudes.
Those tests have been conducted here without affecting vehicles or ships.
Those tests have been conducted here without affecting vehicles or ships.
You don't know the MOD, if they say they are going to 'JAM' the signal, trust me that is exactly what they are going to do.
How they do it, well I would love to know but you can bet they are Jamming Exercises as stated in the AIC referenced in this thread and will be capable of messing up vehicle based GPS units within the stated range. It might occur to you that as the US DOD run the show the MOD might just like to make sure they can locally block the signal if the US DOD don't want to play ball one day.
Join Date: Jul 2006
Location: 32°55'22"S 151°46'56"E
Age: 39
Posts: 594
Likes: 0
Received 1 Like
on
1 Post
In my experience, when GPS Jamming is taking place the GPS unit will alert to degraded or loss of signal. As long as you are aware of how to use your GPS properly.
A failure of the PPL is to ignore GPS completely, rather then properly explore the use and limitations of GPS. When you understand the limitations and errors, you are more confident to use it as the aid that it is.
A failure of the PPL is to ignore GPS completely, rather then properly explore the use and limitations of GPS. When you understand the limitations and errors, you are more confident to use it as the aid that it is.
Join Date: Mar 2011
Location: Essex UK
Posts: 186
Likes: 0
Received 0 Likes
on
0 Posts
SoCal App, thanks for the strange and ominous PM, life is all about making assumptions, but to indicate you really don't know much about the MOD despite your protest:
GPS Jammer Details
3.1 Omni and directional Jammer transmissions centred around 1176.45 MHz (L5), 12270.60 MHz (L2) & 1575.42 MHz (L1) will be
activated to potentially affect receivers tracking GPS signals.
3.2 Two graphic charts supplement this notification and represent the predicted coverage areas from high power and low power jammers
from which a GPS receiver is likely to encounter interference or blocking.
3.3 No allowance is made for airframe masking or the reduction of antenna gain towards the horizon seen in all receiver systems.
Therefore the worse case for receiver vulnerability is considered.
3.4 Low Power (max 10watt EIRP) Jammer coverage
10 ft agl - Areas with clear line of sight of the transmitter;
Up to 30000 ft - 75 nm radius from the transmitter sight.
3.5 High Power (100 watt EIRP) Jammer coverage
10 ft agl - Areas with clear line of sight of the transmitter;
10000 ft -120 nm from the transmitter pointing 220° True within an 80° Beam, less than 27 nm in other directions;
30000 ft - 180 nm from the transmitter centred on 220° True within a 40° beam, 108 nm within an 80° beam, less than 13 nm in other
directions.
If you had actually read the AIC quoted in this thread you would have realised that 'jamming' is not at all misleading. It is exactly what the MOD are going to do, they are going to transmit jamming signals
GPS Jammer Details
3.1 Omni and directional Jammer transmissions centred around 1176.45 MHz (L5), 12270.60 MHz (L2) & 1575.42 MHz (L1) will be
activated to potentially affect receivers tracking GPS signals.
3.2 Two graphic charts supplement this notification and represent the predicted coverage areas from high power and low power jammers
from which a GPS receiver is likely to encounter interference or blocking.
3.3 No allowance is made for airframe masking or the reduction of antenna gain towards the horizon seen in all receiver systems.
Therefore the worse case for receiver vulnerability is considered.
3.4 Low Power (max 10watt EIRP) Jammer coverage
10 ft agl - Areas with clear line of sight of the transmitter;
Up to 30000 ft - 75 nm radius from the transmitter sight.
3.5 High Power (100 watt EIRP) Jammer coverage
10 ft agl - Areas with clear line of sight of the transmitter;
10000 ft -120 nm from the transmitter pointing 220° True within an 80° Beam, less than 27 nm in other directions;
30000 ft - 180 nm from the transmitter centred on 220° True within a 40° beam, 108 nm within an 80° beam, less than 13 nm in other
directions.
If you had actually read the AIC quoted in this thread you would have realised that 'jamming' is not at all misleading. It is exactly what the MOD are going to do, they are going to transmit jamming signals
Join Date: Jun 2006
Location: Dorset
Age: 49
Posts: 173
Likes: 0
Received 0 Likes
on
0 Posts
I still do a full preflight plan and fly timed headings. However, because every silly little airport now demands a control zone, airspace is way too complicated..
Buying a Garmin 695 on Tuesday!
Buying a Garmin 695 on Tuesday!
Join Date: Nov 2001
Location: UK
Posts: 939
Likes: 0
Received 0 Likes
on
0 Posts
Johnm... you sound like the sort of pilot I wouldn't like to be closer to than 100nm. Heck, you can't even spell your occupation right on your profile!
Moreover I'm just checking NOTAMs for a trip home (airways as I write this). I can spell better than most and I have no idea what's in my profile, but I can easily correct it if it makes you happy
Join Date: Jan 2010
Location: Texas and UK
Age: 66
Posts: 2,886
Likes: 0
Received 0 Likes
on
0 Posts
I think that whilst GPS is an excellent tool, it should be remembered that it can be switched off at any point by the authorities. In the early days of GPS two standards existed, civilian and military. The civilian signal was degraded with an error which would be up to 100m, and the error changed every hour. Today we see accuracies of 300mm possible from civilian units.
I can totally understand the reason and need for a jamming unit, all that would do is disrupt the signal from the GPS satellite to the GPS unit making the GPS unusable in the area covered by the jamming transmitter. It’s not rocket science, any radio ham could potentially make one. It would not be legal, but technically not difficult.
The need for a jammer? That’s easy, if we do a Google search for UAV autopilot then it’s easy to find both ready made GPS guided autopilots units for UAV’s (which in their simplest form are model aeroplanes) and build your own unit designs. Now imagine the scenario, somewhere sensitive, or a sensitive event, someone has one of these units (GPS guided device) and its used to position a model aeroplane loaded with something nasty to within a meter of where the person wants it to go.... It becomes a very easily available guided weapon.
I think we have to accept that we live in a very unstable world, that we have no right to GPS services (in fact the use of it should be looked on as a privilege rather than a right) and that the use of it can be removed without notice. WE all need to go back to basics, and remember that GPS can fail, get jammed or be switched off without notice.
I can totally understand the reason and need for a jamming unit, all that would do is disrupt the signal from the GPS satellite to the GPS unit making the GPS unusable in the area covered by the jamming transmitter. It’s not rocket science, any radio ham could potentially make one. It would not be legal, but technically not difficult.
The need for a jammer? That’s easy, if we do a Google search for UAV autopilot then it’s easy to find both ready made GPS guided autopilots units for UAV’s (which in their simplest form are model aeroplanes) and build your own unit designs. Now imagine the scenario, somewhere sensitive, or a sensitive event, someone has one of these units (GPS guided device) and its used to position a model aeroplane loaded with something nasty to within a meter of where the person wants it to go.... It becomes a very easily available guided weapon.
I think we have to accept that we live in a very unstable world, that we have no right to GPS services (in fact the use of it should be looked on as a privilege rather than a right) and that the use of it can be removed without notice. WE all need to go back to basics, and remember that GPS can fail, get jammed or be switched off without notice.
Join Date: Jun 2003
Location: EuroGA.org
Posts: 13,787
Likes: 0
Received 0 Likes
on
0 Posts
I think that whilst GPS is an excellent tool, it should be remembered that it can be switched off at any point by the authorities.
So can ground based navaids, which leaves IFR OCAS exactly where?
Your comments are applicable to the "VFR-only PPL" world only, where one is supposed to navigate with a map+compass like one did in WW1. But remind yourself of the min PPL vis figure, and show me how you do map reading in that.
That's before one gets onto the likelihood of the USA actually switching it off and crippling itself economically.
that we have no right to GPS services (in fact the use of it should be looked on as a privilege rather than a right)
A student of Lord Denning, perhaps?
BTW, SA errors are irrelevant to enroute flight. It was something like 200m which is way better than with any other method. And SA was stopped about a decade ago, and never reintroduced - not even after 9/11.
I agree about amateur UAVs but while that technology has appeared on the retail model aircraft scene only about 3-4 years ago, it was possible long before that. Yet nobody has used it for terrorist purposes. I wonder why? The payload you can carry is very small. A terrorist cell (they rarely work alone) is a significant operation, which needs organisation and needs funding, and they are not going to waste their time and risk getting exposed by doing nuisance stuff like that.
The thing I find funny about these forum debates is how some people are happy to chuck away all the capability we have picked up in recent years and go back to living in the caves. Maybe these people just happen to be very vocal.
Quote:
So can ground based navaids, which leaves IFR OCAS exactly where?
I think that whilst GPS is an excellent tool, it should be remembered that it can be switched off at any point by the authorities.
Join Date: Jan 2001
Location: UK
Posts: 1,089
Likes: 0
Received 0 Likes
on
0 Posts
As IO540 says why should a GPS be a privilidge? Why do we accept so many things from "authorities" as a privilidge and not a right we have earned? Is it the "establishment" trying to keep the peasants in their place? Is your drivers licence described in the same way as your Pilot's licence - i.e. "to exercise the privilidges etc"? Can you imagine the outcry if drivers licences were so worded.
Join Date: Jan 2010
Location: Texas and UK
Age: 66
Posts: 2,886
Likes: 0
Received 0 Likes
on
0 Posts
The reason that we dont live in caves is because we evolved. That’s the same for all technologies. How much payload do you need to cause havoc - its all about the potential to do it and stopping it before it ever happened? A navaid will get you to a point, a known point which is pre defined. A GPS unit will get you to ANY point that someone wants.
Don’t underestimate model aeroplanes, they can come in a range of sizes. Have a look at LMA on Google if your not sure.
I quote below from one UAV autopilots website, surely its easy to see the potential threat from such a unit and the reason that a jamming unit is needed. Its got to be better than switching off all the signals...
Don’t underestimate model aeroplanes, they can come in a range of sizes. Have a look at LMA on Google if your not sure.
I quote below from one UAV autopilots website, surely its easy to see the potential threat from such a unit and the reason that a jamming unit is needed. Its got to be better than switching off all the signals...
- Small size without sacrificing functionality; 28 grams, 4 cm by 10 cm
- GPS waypoint navigation with altitude and airspeed hold
- Completely independent operation including autonomous takeoff, bungee launch, hand launch and landing
- Powerful script language command set
- Open architecture – all state fields fully accessible
- Fully integrated with 3-axis gyros & accelerometers, GPS, pressure altimeter, pressure airspeed sensors, all on a single circuit board
- Extensive data logging and telemetry capabilities
- UAV configuration wizard and installation video simplify installation
I’ve never known a group bang about rights the way pilots do.
You have the right to use GPS. Really, you do. Happy now?
The US government has the right to switch it off, and the MoD have the right to jam it. Where does that put your right? You don’t have the right to stop them, and you probably don’t have the right to action against them nor compensation from them if that happens.
You also have the right to exercise airmanship, which might include identifying single point failures that might impose hazards on the flight.
Staying alive, on the other hand, is not a right but a privilege.
You have the right to use GPS. Really, you do. Happy now?
The US government has the right to switch it off, and the MoD have the right to jam it. Where does that put your right? You don’t have the right to stop them, and you probably don’t have the right to action against them nor compensation from them if that happens.
You also have the right to exercise airmanship, which might include identifying single point failures that might impose hazards on the flight.
Staying alive, on the other hand, is not a right but a privilege.
Join Date: Mar 2011
Location: Essex UK
Posts: 186
Likes: 0
Received 0 Likes
on
0 Posts
Quote:
Originally Posted by Conventional Gear
If you had actually read the AIC
I along with most others have read it. For some reason you seem to think this is all a big deal when it is not. A selective GPS outage in a small part of the UK is hardly an issue.
Originally Posted by Conventional Gear
If you had actually read the AIC
I along with most others have read it. For some reason you seem to think this is all a big deal when it is not. A selective GPS outage in a small part of the UK is hardly an issue.
Sorry, I couldn't resist. But I meant what I said: we each do have the right to use English how we please, even if pedants like me point out that it's not the way an English teacher might teach it.
Join Date: Jun 2005
Location: UK
Posts: 769
Likes: 0
Received 0 Likes
on
0 Posts
Looks like it's not only the aviation community that's worried by GPS jamming.
Military jamming of GPS in Scotland suspended.
Military jamming of GPS in Scotland suspended.
