Doomsday GPS off switch and Control

I have been on this site (mainly reading articles) for quite some time, but I never though I would actually have something to report.

I recently spoke to a man (he did not want to release his name) that worked for Lockheed Martin Space Systems, Valley Forge, Pa (I live in Scranton, PA). Their main contract there was for the GPS IIR and now the later versions of the Global Positioning System Satellites. He informed me that in August 1999 he was working at the facility on the finalization of a satellite that was to be launched in October of that year. He told me that two men (to whom he was not acquainted to and had never seen before) came in to inspect the satellite. Something he though was extremely odd since only authorized personnel are allowed in the clean room, and he personal knew, and had worked with everyone who was authorized for years. When he questioned his supervisor about the indecent the next day he told him that the agents (as he referred to them) where from the Department of Defense and that they always come by to personally inspect the software, and the reason he has never seen them before was that they usually come in on the weekend during the last week of finalization. His curiosity peeked, he told me that he ran a standard diagnostic and noticed that the size of the usual "software package" was a little more that it was supposed to be. He told one of his coworkers and a personal friend about it. His friend took a closer look at the change and found out what it was. He said it was actually a 50-60MB software addition (which he told me was quite substantial in the GPS IIR satellites, since the majority of them run on less that 200MB of software). He said the additional software was a backup "switch" to disable and/or encrypt the GPS satellite signal. What this means is that if the software is activated all devices that do not have the proper "code" to decrypt the signal will no longer function.

You can surmise what you want from this, but I personally believe that this is a Doomsday switch installed by the government. So that if anything happens to threaten the US government or country they can throw the switch and disable all the nations of the worlds GPS capabilities. That means no Aircraft, GPS guided missiles, and even shipping would be extremely hindered.

I'm a pilot and have had GPS systems in both my planes. The first in 1999. We had just gotten GPS access as the DOD had stopped 'skewing' the GPS data. Prior to this the data was unbrelaible and made that way so that hostiles couldn't use GPS guidance. We've always known that the DOD retains the ability to --- as you say --- scramble the GPS system for just that reason. This is pretty common knowledge at least in the aviation field.