GPS System May Begin To Fail In 2010.

Geico266

Geico266

Touchdown! Greaser!
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Geico
Knew that title would get your attention...I saw this report on Fox news earlier today and thought all of you would find it an interesting read.

Mismanagement and underinvestment by the U.S. Air Force could possibly lead to the failure and blackout of the Global Positioning System (GPS), a federal watchdog agency says.

The risk of failure starts in 2010, according to the Government Accountability Office (GAO) report quoted by PC World.

The failure would impact not only military operations, but also the millions of people and businesses who rely on the satellite-based navigation systems built into cars, boats and cell phones.

"If the Air Force does not meet its schedule goals for development of GPS IIIA satellites, there will be an increased likelihood that in 2010, as old satellites begin to fail, the overall GPS constellation will fall below the number of satellites required to provide the level of GPS service that the U.S. government commits to," the GAO report states.

http://www.gao.gov/new.items/d09325.pdf
 
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That's okay, because solar activity is going to peak in 2011-2012 any way, screwing up our GPS signals.

Either way, we have about a year to relearn how to use the compass, and practice our ADF approaches.
-harry
 
Could the GPS system be in jeopardy?

Just happened across this report. If this comes to pass, brush up on your VOR and NDB skills!


"Mismanagement and underinvestment by the U.S. Air Force could possibly lead to the failure and blackout of the Global Positioning System (GPS), a federal watchdog agency says."

http://www.foxnews.com/story/0,2933,520636,00.html

This is a follow up article-
http://www.pcworld.com/businesscent...system_could_begin_to_fail_within_a_year.html

Here is the entire GAO Report-
http://www.gao.gov/products/GAO-09-670T
 
What?!? That cannot be. I thought that we could get rid of LORAN and VOR because we now have GPS. I'm confused.... :-/ ;)
 
the GPS requirements for ADS-B out are looking better and better :-/
 
Nice! All you airplane drivers with nice G1000's and similar gadgets will be wishing they had Fred Flintstone era steam gauges like my Viking Witch!

DSCN2420.JPG
 
Hmm... I'd bet that would make the ADF in my Aztec skyrocket in value! Good thing I know how to use it. ;)
 
How long until Garmin comes out with the 430-A upgrade to add ADF functionality?

Or maybe the 430-L for Loran?


Trapper John
 
Not to worry , the Chinese will have their sats up:frown2:
 
I wonder how many young airline pilots will get lost?

Dan
 
Geico266 said:
Mismanagement and underinvestment by the U.S. Air Force could possibly lead to the failure and blackout of the Global Positioning System (GPS), a federal watchdog agency says.

The risk of failure starts in 2010, according to the Government Accountability Office (GAO) report quoted by PC World.

The failure would impact not only military operations, but also the millions of people and businesses who rely on the satellite-based navigation systems built into cars, boats and cell phones.
Click to expand...

An interesting link. Thanks.

Page 22 of the .pdf (Figure 5) provides a great graph of the probabilities of 18,21,24 satellite constellations. This is good data... but as users, we need to keep in mind that basic GPS 3D positioning only requires view of 4 satellites at a time from the receiver. I regularly see that my Garmins are tracking 7+ satellites.

I suspect that even with a reduced constellation of 21 or 18 satellites, most locations would be able to see 4+ satellites nearly 100% of the time. This would mean our basic positioning needs as pilots will be fulfilled (ie enroute and non-precision GPS approaches).

Having said that... I have not studied how this might affect precision GPS services. For example, WAAS approaches. Do they require more than 4 satellites? How many satellites are broadcasting the WAAS correction signals ?
 
Warnings of my demise are greatly exaggerated... (S. Clemens)

denny-o
 
I suspect that even with a reduced constellation of 21 or 18 satellites, most locations would be able to see 4+ satellites nearly 100% of the time. This would mean our basic positioning needs as pilots will be fulfilled (ie enroute and non-precision GPS approaches).
Click to expand...
We need 4 to make a fix, 5 to detect that one of our satellites is wacky, and 6 to be able to detect the wacky one and ignore it.

Even with 31 satellites, we have brief, localized periods in which we have an insufficient number of satellites with sufficient geometry:
http://www.raimprediction.net/ac90-100/start_applet.html

Presumably what we'll see with a decreasing number of satellites is an increase in frequency of such outages.
How many satellites are broadcasting the WAAS correction signals ?
Click to expand...
My 396 sees 2 waas satellites (#48 and #51), from my house here in Maryland. Maybe it would see more in flight, I never checked from the air. It looks like they're all over the Pacific (at least as of whatever time this web page was accurate):
http://gpsinformation.net/exe/waas.html
-harry
 
... Maybe it would see more in flight, I never checked from the air.
Click to expand...
Actually, it looks like 2 is how many there are. You can see them here as #135 and #138:
http://www.nstb.tc.faa.gov/RT_WaasSatelliteStatus.htm
These will show up as satellites #48 and #51 on a Garmin. That image updates regularly, as the "normal" GPS satellites are continually in motion relative to the surface, but you'll notice that 135 and 138 are always there over the Pacific, as they're geosynchronous.
-harry
 
Speaking of which why are there NOTAMS that GPS will be unreliable over large areas NOW?
 
new military global positioning satellite is heading to orbit after a dawn lift off from the Cape Canaveral Air Force Station.The two-ton satellite lifted off aboard a Delta 2 rocket on Monday around 6:30 a.m. An hour after launch, it moved into a highly elliptical orbit to replace a decade-old GPS 2R-21 spacecraft that will be used as a backup for the new satellite.
The information beamed from the satellite will be used to help the military with field operations and other navigational applications.
This was the last Delta 2 launch that will be done for the Air Force and the last of the GPS 2R satellites to go into orbit.
Click to expand...



http://www.baynews9.com/content/36/...ta+II+rocket+heads+into+orbit++for+final+time


Phase IIIA sats are scheduled to begin in 2013
 
mantakos said:
Actually, it looks like 2 is how many there are. You can see them here as #135 and #138:
http://www.nstb.tc.faa.gov/RT_WaasSatelliteStatus.htm
These will show up as satellites #48 and #51 on a Garmin. That image updates regularly, as the "normal" GPS satellites are continually in motion relative to the surface, but you'll notice that 135 and 138 are always there over the Pacific, as they're geosynchronous.
-harry
Click to expand...

There's also WAAS ground stations all over the US(usually located at FAA center locations).
 
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