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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,5ac12f5a60b1bfe X-Google-Attributes: gid103376,public X-Google-Thread: 101deb,f96f757d5586710a X-Google-Attributes: gid101deb,public X-Google-Thread: f43e6,5ac12f5a60b1bfe X-Google-Attributes: gidf43e6,public From: wtangel@cais3.cais.com (Bill Angel) Subject: Re: Ariane 5 - not an exception? Date: 1996/07/29 Message-ID: <4tiu6e$kpm@news2.cais.com>#1/1 X-Deja-AN: 170923029 references: <4t9vdg$jfb@goanna.cs.rmit.edu.au> organization: Sent via CAIS Internet newsgroups: comp.software-eng,comp.lang.ada,comp.lang.pl1 Date: 1996-07-29T00:00:00+00:00 List-Id: In article <4t9vdg$jfb@goanna.cs.rmit.edu.au>, ++ robin wrote: >In Ariane, both the active processor and the backup failed at >the same time, because it was a *programming* error that was >encountered at the same time in both processors, and both >processors were shut down at the same time by their respective >error handlers. I am under the impression that for the US manned spaceflight program (to get to the moon) ,an on-board computer that was serving as a backup to the primary computer would have been performing its computations using completely different software than the primary computer. By utilizing this methodology, the same software "glitch" would not halt both systems simultaneously. Perhaps a group of software developers could be tasked with producing a version of the on-board software for Ariane in a different computer language than that used by the primary processor. The two processors, running simultaneously, would serve to check each other's results with greater independence that they apparently do now. -- Bill Angel