On Jul 24, 9:43*pm, Eric Greenwell wrote:
On 7/24/2011 8:05 PM, ray conlon wrote: On Jul 24, 10:45 pm, *wrote:

* And the new 4G cellphone- GPS

interference battle is just beginning. The cell phone industry is
promising to deliver billions to the federal coffers, and the FAA cost
the feds $$$, who do you think will win that one?

I'm betting the cell phone people lose this one -

SNIPPED _ CB

At least the problem is not wide spread at the moment. I've never
experienced a GPS problem while flying or driving (except for tunnels
and tall buildings!).


Jamming and spoofing has been a problem for US soaring for years, now.
The sources of jamming and spoofing signals is proliferating, as GPS
uses become
more widespread.

Military testing has spread around the western US from only two sites,
ten years ago,
to multiple sites around popular soaring areas. Fortunately, jam or
spoof activities
from military activities are NOTAMed, which is no consolation if you
are planning an
achievement flight or a contest that happens to be concurrent to
testing.

SSA has helped inform, educate the military and de-conflict military
testing
for some glider events.

In the past two years, we have monitored the Light Squared 4G
frequency
conflict, and participated in public comments on that 'problem', which
is a serious
threat to many aviation users. Their testing offered widespread
potential file
interruption this summer in the West.

Less widely publicized has been WAAS station interference by drivers
with jammers
moving on roadways past approach thresholds at MAJOR hub airports.
Yes, it's
true. Truckers have jammers. They are fortunately, usually localized
in effect,
since they simply want to disable their on-board receivers. But you
don't see that
issue making news media headlines, either.

I have commented to the GNSS-committee members of IGC about these
issues
over the past six years, particularly when some world record altitude
attempts
were imminent using only GNSS-recorders for documentation. (Perlan.)
I was then
poo-poohed for raising issues that "weren't likely to be a problem."
All I asked then
was for consideration of carrying "old" technology for altitude
verification and
continuity, in a location where known jamming was taking place. My
requests
were rebuffed. I still have two 60,000 foot barographs.

Fortunately, the truckers won't influence those potential
achievements. But the solar
flares in the next two or three years might give us other problems.

Steve, I know you have the L/D, but thermal higher !

From the decidely non-technical gal,

Cindy B
SSA Governmental Liaison Committee - Airspace
Region 12 Director