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Comment by chrisacky | Hacker News Reader

This is a little familiar with the rocket failure at Dhahran[1] of 1991 resulting in 28 deaths. The Patriot missile battery at Dhahran had been in operation for 100 hours, by which time the system's internal clock had drifted by one-third of a second. Due to the missile's speed this was equivalent to a miss distance of 600 meters.

Two weeks earlier, on February 11, 1991, the Israelis had identified the problem and informed the U.S. Army and the PATRIOT Project Office, the software manufacturer. As a stopgap measure, the Israelis had recommended rebooting the system's computers regularly. The manufacturer supplied updated software to the Army on February 26.

[1]: https://en.wikipedia.org/wiki/MIM-104_Patriot#Failure_at_Dha...

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While it is a good lesson from a software perspective- your bits are going to overflow, make your software handle that gracefully- I've always been a bit uncomfortable with the blame for deaths being placed on that bug.

The bug didn't kill anyone. The scud missile fired with intent to kill did. And of course, it was fired because it was the Gulf War and countries were attacking each other. Blame who you like for that situation. But all anyone talks about is how it was the Patriot Missile bug that lead to the deaths.

The software bug failed to prevent the deaths that were going to happen anyway. Lessons learned, yes, but I'd hate to imagine a programmer somewhere living in guilt over it.

> The software bug failed to prevent the deaths that were going to happen anyway.

It MAY have failed to prevent the deaths. I don't think Patriot has a 100% success rate. If the normal success rate of that intercept was 1%, 50%, or 99% - it changes the wording a bit I think?

>was 1%, 50%, or 99%

Incidentally, that's about the numbers the pentagon reported, but in reverse chronological order.

http://www.turnerhome.org/jct/patriot.html

The relevant quote:

> Official assessments of the number of Scuds destroyed by the Patriot missile system in the war have fallen from 100 percent during the war, to 96 percent in testimony to Congress after the war, to 80 percent, 70 percent and, currently, the Army believes that as many as 52 percent of the Scuds were destroyed overall but it only has high confidence that the Patriot destroyed 25 percent of the Scud warheads it targeted.

Don't forget the bit after:

> Independent review of the evidence in support of the Army claims reveals that, using the Army's own methodology and evidence, a strong case can be made that Patriots hit only 9 percent of the Scud warheads engaged, and there are serious questions about these few hits. It is possible that the Patriots hit more than 9 percent, however, the evidence supporting these claims is even weaker.

I agree. Really there are two alternatives to what happened.

1. The patriot battery does not have the bug, (or was recently rebooted) and now has a BETTER chance of hitting the scud missile. (but not guaranteed) People may or may not die.

2. The patriot battery is turned off, or not there, and nothing stands in the way of the scud missile. People most likely die.

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