Were there any reports of major systems' failures when the GPS counters rolled over back in August?

-- fatanddumb (fatdumb@nd.happy), November 27, 1999

Answers

There were a number of ground station GPS failures but no sattilite failures. A number of personal GPS receivers failed but the manufacturers had already said that they would. Most could be reprogrmmed. The major failure was in Japan (something to do with the cars).

-- Lobo (atthelair@yahoo.com), November 27, 1999.

On a recent radio show Jim Lord mentioned that the DoD is having problems with some GPS systems. He said there was an article on it a couple weeks ago. Unfortuately I wasn't able to get the details from him. Maybe he will spot this thread and elaborate. KL

-- Kevin Lemke (klemke@corpcomm.net), November 27, 1999.

I requested information on GPS problems from DOD's Y2K Office and received the following information from dated October 22, 1999:

FORWARDED MATERIAL:

"Global Positioning System Anomaly QUESTION: Has the Department of Defense found any problems with the rollover of the Global Positioning System?

ANSWER: The Global Positioning System end of week rollover on August 21, 1999 revealed an incompatibility between GPS receivers and some mission planning systems and precision munitions that exchange GPS week-count. This incompatibility appears in some systems in a back-up or alternate mode, not the normal operating mode.

Although the full impact of this anomaly is still being assessed, all weapon systems remain operational. Straightforward workarounds have been implemented in systems found to be affected.

The GPS satellites, ground control systems, and military receivers are all performing without incident, and the reports from civilian users of GPS appear minimal considering the worldwide application of GPS for land, sea, and air-based navigation. Full identification of this anomaly in the system is expected in the next two weeks. To identify affected systems, the Department of Defense has formed an Anomaly Resolution Support Team, headed by Brig. Gen. Mike Hamel, Vice Commander at Space and Missile Center, Los Angeles, Ca. All users are being contacted and being informed of the anomaly. They are being asked to revalidate their systems and report findings to the Resolution Support Team as soon as possible.

The GPS end of week rollover occurs every 20 years because GPS system time, counted in weeks, started counting on January 6, 1980. At midnight, between August 21 and 22, 1999, the GPS week rolled over from week 1023 to 0000. This was the first rollover since the GPS constellation was established.

The referenced anomaly occurs in the interpretation on the week as either 0000 or 1024.

The GPS rollover matter was not subjected to the Y2K testing program. The Department remains confident in its preparations for Y2K matters, and will use any lessons learned from this experience to further strengthen Y2K readiness efforts. "

END OF FORWARDED MATERIAL

-- abc (abc@ba.com), November 27, 1999.

Following is an article I wrote in the November issue of my newsletter about the current GPS failure.

Jim

-------- GPS Failure

Two months ago I learned from impeccable sources that the military version of the Global Positioning System (GPS) experienced a major problem as a result of the End-of-Week rollover that occurred on August 22.

GPS has two operating modesa high-resolution mode used by the military and a de-graded, low-resolution mode made available to civilian users. The high-resolution mode is accurate to within a foot or so and the low-resolution version to within ten yards or thereabouts.

At first I was very skeptical about this supposed failure because I could not see how there could be a failure of the military system that would not affect civilian users. I eventually learned however that there was indeed a degradation that impacted some mission planning systems and some GPS guided munitions (smart weapons).

Here is what a DOD spokesman said about the failures in an email to Dr. Paula Gordon (who appeared with me on C-Span a while back.)

The Global Positioning System end of week rollover on August 21, 1999 revealed an incompatibility between GPS receivers and some mission planning systems and precision munitions that exchange GPS week-count. This incompatibility appears in some systems in a back- up or alternate mode, not the normal operating mode.

Although the full impact of this anomaly is still being assessed, all weapon systems remain operational. Straightforward workarounds have been implemented in systems found to be affected.

My sources said the problem was significantly more serious than presented above. I was told that for military users it was taking up to three hours to acquire GPS satellites instead of the normal three or four seconds. (Note: the acquisition of a satellite means to locate and begin receiving its signals.) This would be a severe degradation that would indeed impact military operations.

It would mean that when a GPS guided missile or bomb was initiated (turned on) it could not be launched for three hours while waiting to find and lock onto the GPS satellites. To remain ready for use, weapons would have to be be turned on constantly. This condition of readiness is hard on people and equipment and prevents regular maintenance from being performed.

I also think the failure was more widespread than indicated above. Im told it affected the navigational capability of ships, airplanes, troops, etc. This level of degradation would not pose a serious hazard however as there are multiple back-ups available for these navigational functions.

I did not make this information public when I learned of it because to do so would have been of military use to our adversaries. Now that the Department of Defense is admitting the problem I can speak freely. For the first few weeks, I believe we did experience a serious degradation of capability within some of our critical military systems.

This story is important from a Y2K perspective. It shows that a simple date related problem can have serious consequences. It also demonstrates that even when systems are repaired, tested, validated and declared compliant, there can still be problems. Y2K is immensely more complex, extensive and difficult than the GPS roll- over problem. This incident tells us the military is not as ready as they think they are for Y2K.

-- Jim Lord (JimLordY2K@aol.com), November 28, 1999.

I wonder why we used up most of our stock of cruise missiles this summer. Could it be that a firmware change is harder than just upgrading receiver software and we had a "use 'em or lose 'em" situation?

-- ivan (ivan1776@ivnet.net), November 28, 1999.