5 ms·

28 people killed because a clock was off by .34 seconds (system hadn't been restarted in 100 hours) http://fas.org/spp/starwars/gao/im92026.htm http://fas.org/

by dm2 12y ago

28 people killed because a clock was off by .34 seconds (system hadn't been restarted in 100 hours) http://fas.org/spp/starwars/gao/im92026.htm http://fas.org/spp/starwars/gao/im92026.htm

kranner 12y ago
Having followed the link, I'd like to mention that a Scud missile was also involved.
- lttlrck 12y ago
  And a war.
manojlds 12y ago
Isn't it actually "28 lives couldn't be saved" because of the clock issue. Also, the article states that the defense was never tried against SCUD and could have failed nevertheless.
- oakwhiz 12y ago
  I'm guessing that the people wouldn't have been standing within range of missile attacks if they didn't expect that the missile defense system would protect them.
  - x1798DE 12y ago
    Almost everywhere on earth is currently "within range of missile attacks" without any reliable missile defense shield protecting us. From the report, this was during Operation Desert Storm and they were in an Army barracks. Given that these systems had never been used to defend against SCUD missiles before, it seems likely that they were taking a calculated risk by being there, not simply assuming the missile shield would protect them.
    - oakwhiz 12y ago
      I wasn't aware of the speed issues with intercepting SCUDs. Makes a lot more sense when you factor that in - these systems were being used as a last line of defense, not a shield.
- spingsprong 12y ago
  It probably would have failed. The Gulf War Patriot was designed to shoot down Mach 2 jets, not Mach 5 Scuds. Detonating slightly late against an aircraft is actually a good thing, since it makes the Patriot explode near the aircraft's middle instead of its nose. A Scud is a short range ballistic missile. Once it's burnt out its fuel, it just carries on under the influence of gravity. From that point on, the only important part is the warhead in the very tip of the nose. Detonating by the mid section of a Scud means you're just shredding empty fuel tanks. And the huge speeds involved might actually make Gulf War Patriot missiles detonate against the rear of the Scud and just shred the non-functioning engine, or even detonate behind the Scud entirely.
  - umeshunni 12y ago
    "...the delay in distributing the software from the United States to all Patriot locations was due to the time it took to arrange for air and ground transportation in a wartime environment." Fascinating to think that just 23 years ago, the only way to transmit the updated software was by physically transporting it from one location to another.
    - pjc50 12y ago
      I suspect you still can't do OTA updates of this kind of mission-critical system. If you can, I'd be very concerned about security.
      - YokoZar 12y ago
        I don't see any reason the software update process needs to be more secure than the firing process, and presumably these batteries can be fired remotely.
      - umeshunni 12y ago
        You don't need OTA updates per se - they could transfer it using sftp etc to the local base.
    - thaumaturgy 12y ago
- dm2 12y ago
  I think it means that this was the first conflict that it had in against Scuds. There was a software update made a few days before this incident that was in response to another Patriot/Scud engagement. The big issue with this time was that the missile didn't even fire. http://embeddedgurus.com/barr-code/2014/03/lethal-software-defects-patriot-missile-failure/ http://embeddedgurus.com/barr-code/2014/03/lethal-software-d... It's interesting that there were 6 software updates to the Patriot missile batteries during Desert Storm, several of them were specifically to fix the clock errors. It would be interesting to see the data for the misses and the hits compared to how long each system had been online for and what version of the software it was using. Today's patriots are better (PAC-3, PAC-4 in testing) but still have several issues. I remember reading somewhere where a pilot got so mad that he was constantly being locked on by friendly Patriot batteries that he shot a missile at a friendly battery. http://books.google.com/books?id=7cU8Kpzu9osC&pg=PA339&lpg=PA339&dq=HARM+patriot+f16 http://books.google.com/books?id=7cU8Kpzu9osC&pg=PA339&lpg=P... These seem to be mostly RADAR issues, I can't imagine how difficult it would be to program a missile to intercept another missile, there's hundreds of variables involved. I'd be willing to bet that these days they can run them through a computer simulator and detect most of these issues. Unrelated to the missile but relating to the original topic: http://www.wired.com/2012/11/google-spanner-time/ http://www.wired.com/2012/11/google-spanner-time/

by dm2 12y ago

28 people killed because a clock was off by .34 seconds (system hadn't been restarted in 100 hours) http://fas.org/spp/starwars/gao/im92026.htm http://fas.org/spp/starwars/gao/im92026.htm

kranner 12y ago

Having followed the link, I'd like to mention that a Scud missile was also involved.

lttlrck 12y ago
And a war.

manojlds 12y ago

Isn't it actually "28 lives couldn't be saved" because of the clock issue. Also, the article states that the defense was never tried against SCUD and could have failed nevertheless.

oakwhiz 12y ago
I'm guessing that the people wouldn't have been standing within range of missile attacks if they didn't expect that the missile defense system would protect them.
- x1798DE 12y ago
  Almost everywhere on earth is currently "within range of missile attacks" without any reliable missile defense shield protecting us. From the report, this was during Operation Desert Storm and they were in an Army barracks. Given that these systems had never been used to defend against SCUD missiles before, it seems likely that they were taking a calculated risk by being there, not simply assuming the missile shield would protect them.
  - oakwhiz 12y ago
    I wasn't aware of the speed issues with intercepting SCUDs. Makes a lot more sense when you factor that in - these systems were being used as a last line of defense, not a shield.
spingsprong 12y ago
It probably would have failed. The Gulf War Patriot was designed to shoot down Mach 2 jets, not Mach 5 Scuds. Detonating slightly late against an aircraft is actually a good thing, since it makes the Patriot explode near the aircraft's middle instead of its nose. A Scud is a short range ballistic missile. Once it's burnt out its fuel, it just carries on under the influence of gravity. From that point on, the only important part is the warhead in the very tip of the nose. Detonating by the mid section of a Scud means you're just shredding empty fuel tanks. And the huge speeds involved might actually make Gulf War Patriot missiles detonate against the rear of the Scud and just shred the non-functioning engine, or even detonate behind the Scud entirely.
- umeshunni 12y ago
  "...the delay in distributing the software from the United States to all Patriot locations was due to the time it took to arrange for air and ground transportation in a wartime environment." Fascinating to think that just 23 years ago, the only way to transmit the updated software was by physically transporting it from one location to another.
  - pjc50 12y ago
    I suspect you still can't do OTA updates of this kind of mission-critical system. If you can, I'd be very concerned about security.
    - YokoZar 12y ago
      I don't see any reason the software update process needs to be more secure than the firing process, and presumably these batteries can be fired remotely.
    - umeshunni 12y ago
      You don't need OTA updates per se - they could transfer it using sftp etc to the local base.
  - thaumaturgy 12y ago
dm2 12y ago
I think it means that this was the first conflict that it had in against Scuds. There was a software update made a few days before this incident that was in response to another Patriot/Scud engagement. The big issue with this time was that the missile didn't even fire. http://embeddedgurus.com/barr-code/2014/03/lethal-software-defects-patriot-missile-failure/ http://embeddedgurus.com/barr-code/2014/03/lethal-software-d... It's interesting that there were 6 software updates to the Patriot missile batteries during Desert Storm, several of them were specifically to fix the clock errors. It would be interesting to see the data for the misses and the hits compared to how long each system had been online for and what version of the software it was using. Today's patriots are better (PAC-3, PAC-4 in testing) but still have several issues. I remember reading somewhere where a pilot got so mad that he was constantly being locked on by friendly Patriot batteries that he shot a missile at a friendly battery. http://books.google.com/books?id=7cU8Kpzu9osC&pg=PA339&lpg=PA339&dq=HARM+patriot+f16 http://books.google.com/books?id=7cU8Kpzu9osC&pg=PA339&lpg=P... These seem to be mostly RADAR issues, I can't imagine how difficult it would be to program a missile to intercept another missile, there's hundreds of variables involved. I'd be willing to bet that these days they can run them through a computer simulator and detect most of these issues. Unrelated to the missile but relating to the original topic: http://www.wired.com/2012/11/google-spanner-time/ http://www.wired.com/2012/11/google-spanner-time/