GPS interference and contests

Now I ask, NOTAMS or not, why should it be legal for ANYONE to jam a
system which is used in air navigation?

The US military own it, they can jam it or turn it off just as they
please. No law to prevent them.

Mike

Mike the Strike wrote:
Now I ask, NOTAMS or not, why should it be legal for ANYONE to jam a
system which is used in air navigation?

The US military own it, they can jam it or turn it off just as they
please. No law to prevent them.

I don't remember all of the details, but the Department of
Transportation has specific agreements with the DOD dating back to the
early 90s that were put in place to allow GPS to be used to in safety
critical applications (not just aviation, also railroads, timing systems
for the power grid, etc.). Much of the subsequent funding for GPS
satellite upgrades has been explicitly allocated for this purpose. The
DOD can't "jam it or turn it off just as they please", at least within
US territory...

Marc

That's why the Europeans are building Galileo - or did I miss something...

Only the military mind will conceive something of enormous benefit, develop it
with no concern for economics, then intentionally break it because they can.

So the question, in the litigious part of the world must be - is it legally
defensible, to interrupt a service that does not belong exclusively to you, and
which is used by commercial and private civilian users? Let's hope it does not
take a fatal incident to find out.

ESA has not started "commercial" use of its satellites yet - most of it's
stations are terrestrial at present - so I suppose for the very short term the
view that "we own it we can do what we like with it is valid". By 2010 there
will be two satellite systems. Then what?

Mike the Strike wrote:
Now I ask, NOTAMS or not, why should it be legal for ANYONE to jam a
system which is used in air navigation?

The US military own it, they can jam it or turn it off just as they
please. No law to prevent them.

Mike

I agree, but it is a National Security issue-Good luck on changing
that.


On Jan 21, 10:22 am, ZZ wrote:
Even though this thread is related to GPS jamming affecting contest
flight documentation, please allow me this little rant.

GPS navigation is now fully accepted in the US and there are even some
instrument approaches based upon GPS.

Now I ask, NOTAMS or not, why should it be legal for ANYONE to jam a
system which is used in air navigation? Pilots who are fortunate not to
live/fly near a military installation who jam these signals can enjoy
the system. The rest of us have to put up with unreliable/intermittent use.

Is this an issue that the AOPA and the SSA should try to address?

Paul

Bill Daniels wrote:
It seems as if GPS interference testing is becoming more widespread.
See:http://www.navcen.uscg.gov/gps/gpsno...terference.pdf

I wonder if anyone has thought of what might happen if one of these 'tests'
happened near the time an place of a sechduled contest. Basically, you
would lose all GPS systems including loggers. Back to photos? Anyone
thinking about contingencies?

Bill Daniels

The military has vast testing ranges in places like Johnson Island in the
Pacific Ocean. They can test jamming there although it's probably more
expensive than China Lake or White Sands.

The reasons for testing jamming of GPS devices is due to well grounded
concerns about post 9/11 civil defense. You can probably imagine scenarios
so there no need to spell it out in a public forum. The latest block of GPS
satellites will have the capability to deny enemy access in a restricted
geographic area eliminating the need for jamming.

Bill Daniels

"mike" wrote in message
...
I agree, but it is a National Security issue-Good luck on changing
that.


On Jan 21, 10:22 am, ZZ wrote:
Even though this thread is related to GPS jamming affecting contest
flight documentation, please allow me this little rant.

GPS navigation is now fully accepted in the US and there are even some
instrument approaches based upon GPS.

Now I ask, NOTAMS or not, why should it be legal for ANYONE to jam a
system which is used in air navigation? Pilots who are fortunate not to
live/fly near a military installation who jam these signals can enjoy
the system. The rest of us have to put up with unreliable/intermittent
use.

Is this an issue that the AOPA and the SSA should try to address?

Paul

Bill Daniels wrote:
It seems as if GPS interference testing is becoming more widespread.
See:http://www.navcen.uscg.gov/gps/gpsno...terference.pdf

I wonder if anyone has thought of what might happen if one of these
'tests'
happened near the time an place of a sechduled contest. Basically, you
would lose all GPS systems including loggers. Back to photos? Anyone
thinking about contingencies?

Bill Daniels

On Jan 21, 9:22 am, ZZ wrote:
Now I ask, NOTAMS or not, why should it be legal for ANYONE to jam a
system which is used in air navigation? Pilots who are fortunate not to
live/fly near a military installation who jam these signals can enjoy
the system. The rest of us have to put up with unreliable/intermittent use.

Is this an issue that the AOPA and the SSA should try to address?

Paul


Because you're a pilot, YOU are LEGALLY required to avail yourself of
all NOTAMS and such in order to legally fly. Yeah, it sucks --
especially when there is conflicting info, hidden info, Major League
Baseball Games and such.

Jamming GPS is just like a NOTAM that a VOR or ILS or Loran navigation
aid is "out of service," whether for maintenance or due to disaster
(e.g., when Filmore VOR "FIM" was burned in 2006 wildfires). The
NOTAM is to warn you that it's up to you to figure out a different way
to navigate (or document your badge/record flight)...sorta' like
warning you that your battery will fail this week...

Yes, inconvenient. Be glad they NOTAM it, rather than jamming without
telling us.

FWIW, I'm a flight test engineer, working on "something" at NASA-
Dryden, and China Lake GPS jamming _this week_ may interfere with my
livelihood.

Fortunately, they can't move the mountains more quickly than NOAA can
publish paper charts...yet.

-Pete

Does the military ever tell anyone what area is affected by the jamming?
I don't see that in the NOTAM. It seems that would be useful
information.



309 wrote:
On Jan 21, 9:22 am, ZZ wrote:
Now I ask, NOTAMS or not, why should it be legal for ANYONE to jam a
system which is used in air navigation? Pilots who are fortunate not to
live/fly near a military installation who jam these signals can enjoy
the system. The rest of us have to put up with unreliable/intermittent use.

Is this an issue that the AOPA and the SSA should try to address?

Paul


Because you're a pilot, YOU are LEGALLY required to avail yourself of
all NOTAMS and such in order to legally fly. Yeah, it sucks --
especially when there is conflicting info, hidden info, Major League
Baseball Games and such.

Jamming GPS is just like a NOTAM that a VOR or ILS or Loran navigation
aid is "out of service," whether for maintenance or due to disaster
(e.g., when Filmore VOR "FIM" was burned in 2006 wildfires). The
NOTAM is to warn you that it's up to you to figure out a different way
to navigate (or document your badge/record flight)...sorta' like
warning you that your battery will fail this week...

Yes, inconvenient. Be glad they NOTAM it, rather than jamming without
telling us.

FWIW, I'm a flight test engineer, working on "something" at NASA-
Dryden, and China Lake GPS jamming _this week_ may interfere with my
livelihood.

Fortunately, they can't move the mountains more quickly than NOAA can
publish paper charts...yet.

-Pete

On Jan 21, 9:16 pm, Greg Arnold wrote:
Does the military ever tell anyone what area is affected by the jamming?
I don't see that in the NOTAM. It seems that would be useful
information.

See https://pilotweb.nas.faa.gov/distrib...nterQuery.html

or:

!GPS 01/021 ZLA GPS IS UNRELIABLE AND MAY BE UNAVAILABLE WITHIN A 324
NM RADIUS OF 372023.4N/1160158.4W (LOCATED WITHIN THE TONOPAH TEST
RANGE) AT FL400, DECREASING IN AREA WITH DECREASE IN ALTITUDE TO 277
NM RADIUS AT FL250, 198 NM RADIUS AT 10,000 FT MSL AND 197 NM RADIUS
AT 4,000 FT AGL. THE IMPACT AREA ALSO EXTENDS INTO THE MEXICAN FIR.
1900Z-0845Z DLY WEF 0801211900-0801260845

They're describing a VOLUME about the jamming point: the higher you
are (diamond altitude, a little under FL400), the farther you need to
get away to be "unimpacted." Notice they admit the jamming area
includes Mexican airspace. Do you think Europe might be next? Plot
the lat-lon given in SeeYou, draw your circle at FL250 (yeah, it would
be nice if they gave you 17,999) and if your path flies through that
line, your record might be toast.

They've got reasons for doing this, and in the really long view, I
believe that at least SOME of what they do actually protects my
ability (privilege) to fly and soar.

Is it that difficult for IGC to allow camera backup to Logger GPS
traces? For those that think there's an ulterior motive, I sold my
Kodak stock years ago.

Or should I take up bowling, instead?

-Pete

Bruce wrote:

ESA has not started "commercial" use of its satellites yet - most of
it's stations are terrestrial at present - so I suppose for the very
short term the view that "we own it we can do what we like with it is
valid". By 2010 there will be two satellite systems. Then what?

Technically, there are already two: GLONASS is the other, though I'll
admit I've never seen a receiver for it. I read the other day that it
had rather fallen on hard times, but that the Russians are about to
bring the constellation back to full strength and possibly to open it up.

I wonder if either Galileo or GLONASS will provide better polar coverage
than GPS?

There seems to be some confusion as whether current GPS receivers will
work with Galileo. I understand that the frequencies are similar and the
satellite IDs have been arranged to avoid clashes. I asked this question
after an article on Galileo appeared in New Scientist: apparently the
correct answer is "suck it and see" because nobody knows for sure.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

309 wrote:
On Jan 21, 9:16 pm, Greg Arnold wrote:
Does the military ever tell anyone what area is affected by the jamming?
I don't see that in the NOTAM. It seems that would be useful
information.

See https://pilotweb.nas.faa.gov/distrib...nterQuery.html

or:

!GPS 01/021 ZLA GPS IS UNRELIABLE AND MAY BE UNAVAILABLE WITHIN A 324
NM RADIUS OF 372023.4N/1160158.4W (LOCATED WITHIN THE TONOPAH TEST
RANGE) AT FL400, DECREASING IN AREA WITH DECREASE IN ALTITUDE TO 277
NM RADIUS AT FL250, 198 NM RADIUS AT 10,000 FT MSL AND 197 NM RADIUS
AT 4,000 FT AGL. THE IMPACT AREA ALSO EXTENDS INTO THE MEXICAN FIR.
1900Z-0845Z DLY WEF 0801211900-0801260845

They're describing a VOLUME about the jamming point: the higher you
are (diamond altitude, a little under FL400), the farther you need to
get away to be "unimpacted." Notice they admit the jamming area
includes Mexican airspace. Do you think Europe might be next? Plot
the lat-lon given in SeeYou, draw your circle at FL250 (yeah, it would
be nice if they gave you 17,999) and if your path flies through that
line, your record might be toast.

The 277 nm radius at FL250 roughly covers San Francisco to the west, San
Diego to the south, and Salt Lake City to the east. I am not sure that
this information is terribly helpful for pilots (power as well as
soaring) who would like to know if they can believe what their GPS is
telling them.


They've got reasons for doing this, and in the really long view, I
believe that at least SOME of what they do actually protects my
ability (privilege) to fly and soar.

I am skeptical.



-Pete