GPS Jamming Trials

[david viewing]

COM : FROM 04/03/08 08:00 TO 04/03/14 16:00 B0391/04
D)JAMMER A: MAR 08-14 0800-1600
JAMMER B: MAR 09, 10, 11 2200-2245
E)GPS JAMMING EXERCISES.
GPS SIGNALS (1227.60MHZ AND 1576.42MHZ) WILL BE JAMMED DURING PERIODS
STATED ABOVE, GROUND BASED JAMMERS WILL BE LOCATED WI 3KM OF 5201N
00336W (SENNYBRIDGE DANGER AREA).
JAMMER A: OMNI DIRECTIONAL AFFECTING ACFT WI RAD 68NM (DEPENDING ON
ALTITUDE)
JAMMER B: DIRECTIONAL AFFECTING ACFT AT A DISTANCE OF UP TO 210NM IN
THE SECTOR 180 THROUGH TO 240 DEG (DEPENDING ON ALTITUDE).
THE EMERGENCY CEASE JAM POINTS OF CONTACT ARE:
EXERCISE OPERATIONS 01874-635599
TRIALS MANAGER 07813-592626
DURING THESE PERIODS, GPS RECEIVERS MAY SUFFER INTERMITTENT OR TOTAL
FAILURE, OR GIVE INCORRECT POSITION INFORMATION. CREWS SHOULD BE
AWARE OF THESE LIMITATIONS AND USE ALTERNATIVE MEANS OF NAVIGATION.
THE POLICY FOR THE USE OF GPS FOR U.K. AIR NAVIGATION SEVICES IS
GIVEN IN AIC 93/2002 (PINK 41)


Surely the powers that be are not interfering with GPS just to teach lazy, slapdash PPL's who rely on it as a primary means of navigation a timely lesson?

Conspiracy theories aside, can anyone suggest a satisfactory reason why it should be neccesary for the authorities to jam this important public service on such a comprehensive and extended basis?

[PhilD]

I haven't got my map handy. In plain english approximately what area does this cover?

Thanks

[Evo]

GROUND BASED JAMMERS WILL BE LOCATED WI 3KM OF 5201N
00336W (SENNYBRIDGE DANGER AREA).

The middle of south wales, so

JAMMER A: OMNI DIRECTIONAL AFFECTING ACFT WI RAD 68NM (DEPENDING ON ALTITUDE)

...most of South Wales...

JAMMER B: DIRECTIONAL AFFECTING ACFT AT A DISTANCE OF UP TO 210NM IN THE SECTOR 180 THROUGH TO 240 DEG (DEPENDING ON ALTITUDE).

...and some parts of Devon and Cornwall. I think (edit: i haven't got my map handy either). :)

[BEagle]

"A very large chunk of some very busy airspace" Plain enough?

If these 'trials' are really so vital, why not do them in St Kilda or somewhere else in the middle of nowhere. Why must they be done in S Wales?

Oh - of course. It's cheaper for the mad boffins.

Really b£oody handy to have 'cease jamming' phone no.s! What is the 'cease jamming' safety frequency?

[M609]

ATC should be able to help me thinks. We will have the same deal up here next week due to the Livex part of "Joint Winter 2004". We have a "kill the jammer" phone-number....... :O

Now, the planned jamming of Mode 3A system on the AWACS that "will not affect other radars" gives me goosebums..... :ugh:

[david viewing]

PhilD

Your'e not alone in not knowing where this is. It doesn't get plotted by the Notamplot/Avbrief combination. You'd think the boffins who have a licence to jam GPS over a large part of the country would know how to write a Notam, wouldn't you.

Still, I'm sure there is an overwhelming national need for this not very dangerous disruption of GPS.

[WorkingHard]

So as we no longer have uninterupted airband signals the radio licence is null and void and the RCA can go to hell on next demand

[IO540]

david viewing

While nobody who knows for sure won't be posting it here, it is now pretty widely believed that if there was a major threat to the West from (presumably GPS guided) long range missiles, the Americans would not switch off the whole system; they would selectively jam it over certain areas, and they (and very few others) have the technology to do this in such a way that commercial-grade GPS receivers (even those with RAIM) would not report a problem.

I suppose the purpose of the jamming tests is to test some system which would come into operation in such circumstances.

I don't think anybody cares about GA use of GPS; most people use GPS anyway whatever the anti-GPS old-timers think of it.

[BEagle]

Quite so.

In which case, do the trials in a remote area at a quiet time of night! Not in a relatively busy area during the day.

Or can't they afford the travel budget?

[Evo]

Or can't they afford the travel budget?

C'mon, If they paid for travel how would QinetiQ afford the project management....? ;)

[Mr Wolfie]

It does seem a bit much - whilst Senny Bridge may itself be the back of beyond, the 68NM range of the omnidirectional jammer extends into Cardiff, Bristol & Birmingham's CAS.

Why not run trials on Rockall, at midnight?!

Mr. W

PS. It isn't the first time either. There were extensive GPS jamming trials at Senny Bridge NOTAMed last year too.

[boomerangben]

For your information, they do do jamming trials in the remote areas of NW Scotland on a fairly regular basis. When it is NOTAMed up here, it seems to be centred on a potentially sensitive site. Could that be the reason for the trials down there? Maybe also it is to give assault ships and pilots practice at precision navigation without the satelites. Something we should all take some time to practice occasionally.