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=-0.9 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD, FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4 X-Received: by 2002:a6b:b757:: with SMTP id h84mr55753334iof.193.1555591455573; Thu, 18 Apr 2019 05:44:15 -0700 (PDT) X-Received: by 2002:aca:3c55:: with SMTP id j82mr1680015oia.84.1555591455332; Thu, 18 Apr 2019 05:44:15 -0700 (PDT) Path: eternal-september.org!reader01.eternal-september.org!feeder.eternal-september.org!weretis.net!feeder6.news.weretis.net!feeder.usenetexpress.com!feeder-in1.iad1.usenetexpress.com!border1.nntp.dca1.giganews.com!nntp.giganews.com!136no145485itk.0!news-out.google.com!w17ni181itb.0!nntp.google.com!b2no144838itd.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Thu, 18 Apr 2019 05:44:15 -0700 (PDT) In-Reply-To: <03d33940-85e9-4fc9-9f2b-2b43f2cfd6af@googlegroups.com> Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=165.225.72.207; posting-account=bMuEOQoAAACUUr_ghL3RBIi5neBZ5w_S NNTP-Posting-Host: 165.225.72.207 References: <8736mwi257.fsf@nightsong.com> <2590d3d8-5f91-4f59-897e-e0c9b7e1b5ca@googlegroups.com> <5f483f72-9213-4c63-b3f9-7150fc4e455f@googlegroups.com> <03d33940-85e9-4fc9-9f2b-2b43f2cfd6af@googlegroups.com> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: <47a71ba7-38cb-426b-8dad-564f08afbcb2@googlegroups.com> Subject: Re: Boeing 737 and 737 MAX software From: Maciej Sobczak Injection-Date: Thu, 18 Apr 2019 12:44:15 +0000 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Xref: reader01.eternal-september.org comp.lang.ada:56152 Date: 2019-04-18T05:44:15-07:00 List-Id: > True, airspeed needs not be computed this way. But it must be somehow com= puted. Note that the airspeed had to be computed (or measured) long before the new= sensor was invented, so presumably the method of computing it was not taki= ng the new sensor into account anyway. And I don't expect that method to be= changed just because some new sensor is installed. I don't see any reason for using this addition anywhere in the system. > True, it is possible that the software was written in Ada. But then, the = fact that it didn't raise an exception If the addition was never performed (because there was no reason to do it),= then it is quite reasonable that no exception was raised. One could imagine a contract that binds several such values in constraints = that are motivated at the system-level and this is arguably where Ada could= help. But I doubt such novel programming techniques would be even consider= ed. > indicating a failure to detect/handle so "exceptional" situations as AoA = implying negative [horizontal] airspeed, is simply unbelievable. Why? The new sensor was not installed to detect negative airspeed, but to d= etect stalls. This system might have been written in Ada or C (I don't expect anything el= se to be even considered) with the same results. Which, arguably, is not he= lping to promote the language (whichever was used). --=20 Maciej Sobczak * http://www.inspirel.com