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 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: a07f3367d7,7c1ca6be7961c074 X-Google-Attributes: gida07f3367d7,public,usenet X-Google-NewGroupId: yes X-Google-Language: ENGLISH,ASCII Path: g2news2.google.com!postnews.google.com!e20g2000vbc.googlegroups.com!not-for-mail From: Martin Newsgroups: comp.lang.ada Subject: Re: OT?: AF 447 and avionics software Date: Thu, 4 Jun 2009 04:02:46 -0700 (PDT) Organization: http://groups.google.com Message-ID: References: <78pifuF1k9uvuU1@mid.individual.net> NNTP-Posting-Host: 20.133.0.8 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: posting.google.com 1244113366 25494 127.0.0.1 (4 Jun 2009 11:02:46 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Thu, 4 Jun 2009 11:02:46 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: e20g2000vbc.googlegroups.com; posting-host=20.133.0.8; posting-account=g4n69woAAACHKbpceNrvOhHWViIbdQ9G User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9.0.11) Gecko/2009051909 Firefox/3.0.11,gzip(gfe),gzip(gfe) Xref: g2news2.google.com comp.lang.ada:6227 Date: 2009-06-04T04:02:46-07:00 List-Id: On Jun 4, 10:29=A0am, "Alex R. Mosteo" wrote: > I'm sure most of us are following the news on this issue. I just read an > article where an 'expert' questions "damn computers". Particularly this > quote: > > "In these fly-by-wire systems, one never really knows if one has checked = out > all possible combinations of events to make sure that the computer proper= ly > reacts," > > http://www.time.com/time/world/article/0,8599,1902421,00.html > > Frankly I know nothing about the aviation standards for software/computer > use, but I suspect it is somewhat more strict than "one never really know= s". > I mean, surely you can't test everything, but I guess one can be reasonab= ly > confident on the system design! > > Now, there's a trend forming pointing to the ADIRU [1] unit, because of > recent incidents like the Qantas flight mentioned in the article. I'm not > sure there's really verified reasons to point to it yet but, trying to st= ay > on topic: > > I think Airbus is mainly Ada, right? Do you know some good place to read > about its software systems? > > What about these ADIRU units, are they delivered to Airbus by some provid= er > or are of their own built? > > [1]http://en.wikipedia.org/wiki/Air_Data_Inertial_Reference_Unit They can analysis code to ensure absense of runtime error (e.g. using SPARK and/or tools like PolySpace) but testing all possible scenarios is a different kettle of fish all together. The systems may even do everything that was required of them but how do you 'test' the requirements are 'sensible'?.. Cheers -- Martin