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GPS Transitions to New Control System

Posted by Zonk on from the angels-on-our-shoulders dept.

gsfprez writes "It took us a long time, but the Air Force has finally moved off of the 1970's mainframe GPS control system and is now running on a new Unix-based Control System called AEP — Architecture Evolution Plan. It's important to remember that current GPS satellites are basically solar powered iPod shuffles with atomic clocks that simply playback whatever we upload into them at a precise rate. They don't actually have any idea where they are — its the control system at Schriever Air Force Base that does. The new system will be a lot cheaper to support and modify since Sun stocks things like SATA drives - while digging up Saturday Night Fever-era DASDs isn't simple. AEP will also allow us to be ahead of the curve: we're basically good to go to fly the new IIF birds."

4 of 170 comments (clear)

  1. Re:i was edited and my points were lost.... by Santheman · · Score: 4, Interesting

    I was at "Schriever" (Falcon back then) from 1992 to 1994 and the GPS DASDs were being replaced. I know, as I was in the GPS module on a daily basis and the new drive enclosures were microscopic compared to the DASDs. Not sure where the GPS DASD references are coming from. The GPS module was the first to replace the DASDs as they had all the money. San

  2. Hope the reliability is just as good! by ErichTheRed · · Score: 4, Interesting

    This is by no means a "keep the legacy crap" rant -- systems you can't buy parts for without an unlimited budget should be retired ASAP.

    However, I wonder who's handling the conversion for them, or if the Air Force is doing it themselves. I've seen great legacy conversion projects, and been involved in some really awful ones. One problem is just a lack of people who know enough about the "old" system to implement the software in the "new" side. The other, and far worse one is when companies (not militaries, mind you) bring in contractors who know _nothing_ about the hidden surprises in the old system, or nothing about the actual real-world application the computer is supporting.

    As long as the system's not running J2EE or outsourced to a bunch of "expert" consultants, I'm guessing we're fine. But there is one key thing that's lost on "modern" IT -- proven systems work. Just because something is new doesn't mean it will work better! This is why I'm glad they stuck with UNIX instead of Linux or Windows.

    Side note, how much do you think IBM was charging to maintain that monster??

    1. Re:Hope the reliability is just as good! by PhxBlue · · Score: 3, Interesting

      There were a lot of agencies involved. The GPS Wing at Los Angeles AFB was the procurement agency for the new system. Other federal agencies had to be involved with the process, because they're stakeholders -- the Department of Agriculture and the FAA, for example, have a vested interest in making sure GPS "just works."

      The 2nd Space Operations Squadron and the 19th Space Operations Squadron at Schriever Air Force Base are the primary operators of GPS. Within the squadrons, you have a wide variety of expertise -- airmen, government civilians, and contractors from the companies that developed both the new ground segment and the satellites that are on-station. Some of them are two-stripers just out of technical school ... some are contractors who've been in the business just as long as GPS itself.

      --
      !#@%*)anks for hanging up the phone, dear.
  3. Re:Wait... only one base providing data refersh? by DerekLyons · · Score: 3, Interesting

    Given that pretty much all our military's high-accuracy munitions depend on GPS for their "smartness", there is almost certainly a redundant control system elsewhere. Possibly with the 1st Mob or the 3rd Herd, which are expeditionary forces so they aren't sitting ducks like an Air Base is.

    Probably not with either - as the ground control system is pretty big and delicate [1], pretty power hungry, and requires a fair number of specially trained personell [2] to operate it. It isn't something you are going to do in the back of a Humvee or a Bradley. You'd be hard pressed to do it in much of anything mobile short of the a Tico or a CVN.
     
    That being said, the current generation of GPS birds are designed to operate autonomously for (IIRC) at least a month, though it will be some years before the entire constellation is upgraded to that standard. This implies the existence of a 'cold' backup somewhere else.
     
    Insofar grandparents concern about 'high energy nukes' goes... He's pretty much out to lunch. The GPS constellation isn't as vulnerable to EMP/radiation effects as 'normal' LEO birds are because a) they are designed to be resistant to EMP, and b) the GPS constellation isn't inside the inner Van Allen belt like the birds wrecked by Starfish. You are pretty much in the situation of having to, even with nukes, take out each bird individually. (Sometimes they are close enough that you might be able to get 3-4, but the constellation is redundant enough that this won't take the system down.) So you are talking a pretty expensive and hard to hide endeavor, and being unable to take down enough of the cluster in a short enough timeframe to hamper US operations... before your own country is a glass parking lot.
     
    I know many Slashdotters may have a hard time believing this - but they did actually think this stuff through when they designed the system.
     
    [1] It's not just computers, but communications systems, precise clocks, etc... etc...
     
    [2] Not just the techs that maintain the hardware above but the analysts that work with the incoming data to generate the corrections.