Posted on 12/16/2004 7:04:56 AM PST by crushelits
WASHINGTON - President Bush has ordered plans for temporarily disabling the U.S. network of global positioning satellites during a national crisis to prevent terrorists from using the navigational technology, the White House said Wednesday.
Any shutdown of the network inside the United States would come under only the most remarkable circumstances, said a Bush administration official who spoke to a small group of reporters at the White House on condition of anonymity.
The GPS system is vital to commercial aviation and marine shipping.
The president also instructed the Defense Department to develop plans to disable, in certain areas, an enemy's access to the U.S. navigational satellites and to similar systems operated by others. The European Union is developing a $4.8 billion program, called Galileo.
The military increasingly uses GPS technology to move troops across large areas and direct bombs and missiles. Any government-ordered shutdown or jamming of the GPS satellites would be done in ways to limit disruptions to navigation and related systems outside the affected area, the White House said.
(Excerpt) Read more at washingtonpost.com ...
They then showed me their panels. Nothing but dead reckoning and a handheld that a member of each crew purchased on their own dime just in case. I was amazed! One guy flies and the rest just follow the one who presumably knows where he's going. They cannot fly IFR.
I think we can't track down where the postings are coming from because organisations like Al Jazeera, Middle Eastern ISPs are helping them.
I probably wasn't succint enough regarding the GPS - sure, they could utilise a handheld device, but I doubt they could do anything much with regard to screwing up the GPS system itself.
Just thinking aloud. I never really thought about them using it during the 9-11 attacks. Also, I wouldn't classify the guys that piloted the plains in the same category as the guys fighting and living in caves. The guys in the planes were educated middle class guys from Germany.
And because we are fighting for freedom and life, not enslavement and a culture of death.
"IIRC, the GPS isn't really "shut down" it's encrypted to ensure authorized use only.
I could be wrong but I'd swear that was what I was taught in 1992 when I first trained on the GPS."
Essentially correct.
Prior to Desert Storm, Commercial GPS capability was limited to something on the order of 10 +/- meter accuracy. THis provision and control measure could be re-introduced, providing military applications with the required 1 meter +/- accuracy
Here's is some data Art Bell should know about..
Completely disabling the GPS signal would also disable the majority of Digital Telecommunications within approximately 24 hours.
All digital telecommunications today require a "timing reference source" to keep terrestrial and "over the air" things in sync. Before GPS, extremely high tolerance clocks were used. With the advent of GPS, timing is largely derived via the matrix of signals emitted by GPS satellites, which is a much cheaper source (free) than expensive stratum clocks.
A shutdown of the GPS signal would not immediately disable the network as a hierarchy of the clocks remain and are still installed in telecom equipment. The most important components such as the largest telephone switching computers highest in the hierarchy of the telephone network will remain on-line indefinately however equipment at the edge such as Cellular Telephone base sites could be off-line in an hour or less. Especially those that use the CDMA air interface standard (Verizon, Sprint PCS). Network connections to smaller telephone switching computers would start to fail in 24-48hrs.
At some point after 9/11, there were stories about GPS transponders that were found in buildings adjacent to the WTC area. They were somehow linked to the hijackers being able to redirect the planes to the correct coordinates to hit the buildings. I am sure that someone here at FR recalls this info., or has articles from that time that back-up my recollection.
1) The window. 2) Unlike land travel, dead reckoning, using only a compass and clock, is amazingly accurate but you have to do some math work before the flight for this to viable. 3) AM radio stations can be homed in on using a $10,000 auto-direction finder if you have one. 4) Receiving VOR navigation signals. The system has transmitter stations placed about 50 miles from each other all over. The way they work is the time difference between a beacon signal and a rotating directional signal provides your bearing from the station. Receiving 2 stations you can get a fix. This is currently the most popular method of air navigation. However GPS is taking over as it is more accurate, easier to use, and cheaper.
Have you ever wondered what would have happened on 9-11 if the weather had not been CAVU in both New York and DC? Maybe the terrorists had to wait until they were sure of VFR weather both places (and who knows what other places). Even had they been able to use GPS to navigate to downtown Manhattan, hitting those buildings would have been like threading a needle for an inexperienced jetliner pilot.
My suggestion to anyone flying commercial is to fly at night only. They can't find a damn thing and thus would be less likely to waste the flying missile by missing their target. The flight crews and radar controllers are always much nicer at night as well.
If that's the case, then I find that astonishing. That would indicate an operation of a much more colossal scale than I would've thought. I always thought it was a crude attack with the box cutters being their only tool.
And it can be done in stages. AFAIK, the precision "code" is available to all right now. That can be encrypted so that only military users can get the most accurate position information needed for weapon guidance. Others can still get lower quality position information.
Hate to be landing a 747 in fog when GPS gets turned off.
Or much worse, if it is spoofed or bent, to cause a GPS guided missile heading for a building to land in the countryside.
Ever hear an Arab pilot give a readback? It's incorrect after the third word and the ground controller doing the sequence just gives up and makes a special departure for them. It's pathetic.
Anybody can use commercial off the shelf aviation and marine GPS navigation gear to steer a plane or cruise missile to a target. This equipment is standard for boats and planes, it links the autopilot to the GPS. You just put in the exact coordinates, and tell the boat or plane to go to that "waypoint." And it will. Even if the plane is a Learjet loaded with explosives, and the "waypoint" is the Whitehouse.
Even in degraded accuracy, ten or 100 meters would be plenty to allow an anthrax laden Cessna to find downtown Washington. We have to be ready in that case to "shift" the GPS to make the plane go elsewhere. The downside is, planes and boats in that area will go off course on autopilot, perhaps with disastrous results. Hence the need here to give advance warning to the marine and aviation community that GPS might be "turned off" suddenly. I imagine there will be warning given to go off of GPS autopilot navigation immediately, to prevent accidents.
I believe the Marines found GPS equipment in Fallujah when they were doing their raids last month.
Perhaps an old non-WAAS GPS???
I have a Garmin 196 in my airplane, but the GPS systems we deal with in agriculture have <1meter precision with WAAS. We've had them for 3-4 years now.
We have one very high end system that uses "RTK", real time kinematic, to get < 1 inch precision using a local differential.
Taking down GPS would basically wipe out the modern surveying industry. I'd bet most of these guys would have to re-train on how to use the old equipment. If they still have it.
GPS just isn't that big of a deal. I'm sure you can buy a GPS at the local Walmart.
The idea of shutting down GPS totally is really dumb. There's just way to many industries now totally dependent on it. Aviation probably has the best fall back equipment. But there are agricultural, telecommunications, surveying, and marine that would be hit hard.
Shutting down GPS totally is really out of the question, except for some kind of 9/11 repeat. Which is not very likely. Tod Beamer showed us how to deal with that. Aircraft will not likely ever be hijacked again by terrorists in the cockpits.
GPS guided "cruise missles" though are a possibility. And the best defense against that would be local jammers around DC. I've got to think they've already got them there. A couple of years ago they tested GPS jamming somewhere offshore, so the equipment exists.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.