From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,da26f7e99d6cfcf3 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-04-09 11:14:06 PST Path: supernews.google.com!sn-xit-03!supernews.com!newsswitch.lcs.mit.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newsfeed1.earthlink.net!newsfeed.earthlink.net!newsmaster1.prod.itd.earthlink.net!newsread2.prod.itd.earthlink.net.POSTED!not-for-mail From: "Phaedrus" Newsgroups: comp.lang.ada References: <9Pxz6.992$ix4.198187@news1.rdc1.sfba.home.com> Subject: Re: software failure question X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Message-ID: <4ZmA6.1693$Ak1.181271@newsread2.prod.itd.earthlink.net> Date: Mon, 09 Apr 2001 18:13:20 GMT NNTP-Posting-Host: 209.178.105.92 X-Complaints-To: abuse@earthlink.net X-Trace: newsread2.prod.itd.earthlink.net 986840000 209.178.105.92 (Mon, 09 Apr 2001 11:13:20 PDT) NNTP-Posting-Date: Mon, 09 Apr 2001 11:13:20 PDT Organization: EarthLink Inc. -- http://www.EarthLink.net Xref: supernews.google.com comp.lang.ada:6669 Date: 2001-04-09T18:13:20+00:00 List-Id: I'm reminded of another famous software failure, that may or may not be an urban legend: According to the story, when programming a helicopter simulation for the Australian military, someone noticed that they didn't have any kangaroos. Rather than write a whole bunch of new code to simulate them, they just derived a new subclass from the class that they used to simulate the ground troops. When they flew the new version of the simulation, the kangaroos scattered just as expected when the helicopter flew over the hill. But imagine their surprise when the 'roos came back and started firing at the chopper with surface-to-air missiles! Phaedrus wrote in message news:9Pxz6.992$ix4.198187@news1.rdc1.sfba.home.com... > Anyone know where this came from? > "In one infamous software error, a misplaced minus sign resulted in a > fighter jet's control system flipping the aircraft on its back whenever > it crossed the equator. " > http://www.newscientist.com/dailynews/news.jsp?id=ns9999595