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=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!feeder.eternal-september.org!news.linkpendium.com!news.linkpendium.com!news.snarked.org!border2.nntp.dca1.giganews.com!nntp.giganews.com!buffer2.nntp.dca1.giganews.com!buffer1.nntp.dca1.giganews.com!news.giganews.com.POSTED!not-for-mail NNTP-Posting-Date: Sat, 06 Apr 2019 12:30:31 -0500 From: Dennis Lee Bieber Newsgroups: comp.lang.ada Subject: Re: Boeing 737 and 737 MAX software Date: Sat, 06 Apr 2019 13:30:31 -0400 Organization: IISS Elusive Unicorn Message-ID: <5rnhael4n4dunnbrcs5o2t5tnua2t3iunh@4ax.com> References: <8736mwi257.fsf@nightsong.com> User-Agent: ForteAgent/8.00.32.1272 X-No-Archive: YES MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Usenet-Provider: http://www.giganews.com X-Trace: sv3-qTECXOAqswOtg+rkoNzRPyn3v4D0n1XRuciRNtJdH52Gy1W4CKto8+Vous72Jg57NqFQHb/9QJsqkXe!WqYHxEvtAbsui9tn3CCnzDG9nZplt6FD3BbEmGWNG4r6NMG2M0jvhi/UmvidbZZP2Tci9QQF X-Complaints-To: abuse@giganews.com X-DMCA-Notifications: http://www.giganews.com/info/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 2391 Xref: reader01.eternal-september.org comp.lang.ada:56089 Date: 2019-04-06T13:30:31-04:00 List-Id: On Fri, 05 Apr 2019 14:16:20 -0700, Paul Rubin declaimed the following: >Does anyone know anything about this? It has been under some criticism >lately. > >I have heard that the 777 software was almost entirely in Ada. It also >sounds as if Boeing's software operation may have slipped in recent >years, not good news for the 737 MAX. Unless things have changed severely -- GE Aviation (formerly Smith's Aerospace, formerly Lear Siegler) produces the 737 FMS software (and also the processor boxes). However, I have the impression (from TV news) the software is functioning /as designed/. Some reports have indicated that Boeing designed the hardware (and corresponding software requirements) such that only one sensor is used for the MCAS subsystem -- and a fault in that sensor results in MCAS attempting to prevent a (non) stall by pushing the nose down. Some hints in the news that Boeing is changing the requirements (well, in truth, the news only says Boeing is changing the software) to have MCAS cross-reference with other flight parameter data -- and making an optional bit of hardware (additional sensors) standard. -- Wulfraed Dennis Lee Bieber AF6VN wlfraed@ix.netcom.com HTTP://wlfraed.home.netcom.com/