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From: Lloyd Fischer <lloyd@dvcorp.com>
Subject: Re: Ariane 5 - not an exception?
Date: 1996/07/30
Date: 1996-07-30T00:00:00+00:00	[thread overview]
Message-ID: <31FE054D.6CE1@dvcorp.com> (raw)
In-Reply-To: 4tiu6e$kpm@news2.cais.com


Bill Angel wrote:
> 
> In article <4t9vdg$jfb@goanna.cs.rmit.edu.au>,
> ++           robin <rav@goanna.cs.rmit.edu.au> 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
A better example is the flight control system for the A320 aircraft.
From memory now: there are 4 flight control computers, each controlling
separate hardware. The computers are of two types, with different
hardware and software. The designers of each type were completely
isolated from the designers of the other. The idea is that the computers
battle for control of the plane. If one computer generates completely
erroneous controls the other three can completely overpower it. If one,
two, or three die there is no problem. I can't recall if the computers
have the power to cause the shutdown of an offender and how the handled
the 2 vs. 2 problem.



If anyone has a spec for the A320 system please pipe in. I'm out of
aerospace now and can't just run down to the library.

IMHO the ariane, 4 and 5, with two computers running the same software
is a systemic error just waiting to happen. 
-- 
Lloyd Fischer  lloyd@dvcorp.com  fischer@crocker.com (home)  
DataViews Corporation                  |
47 Pleasant St, Northampton, MA 01060  | from disclaimers import
standard
Voice 413 586-4144 Fax 413 586-3805    |




  parent reply	other threads:[~1996-07-30  0:00 UTC|newest]

Thread overview: 194+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1996-07-25  0:00 Ariane 5 - not an exception? Simon Bluck
1996-07-25  0:00 ` Multiple reasons for failure of Ariane 5 (was: Re: Ariane 5 - not an exception?) Kirk Beitz
1996-07-26  0:00   ` Robert I. Eachus
1996-07-26  0:00   ` ++           robin
1996-08-05  0:00     ` Darren C Davenport
1996-08-06  0:00       ` U32872
1996-08-07  0:00         ` Robert Dewar
1996-08-08  0:00           ` Pascal Martin @lone
1996-08-09  0:00             ` Robert Dewar
1996-08-10  0:00               ` dwnoon
1996-08-11  0:00                 ` Robert Dewar
1996-08-15  0:00                   ` dwnoon
1996-08-16  0:00                     ` Robert Dewar
1996-08-20  0:00                       ` dwnoon
1996-08-12  0:00                 ` Ken Garlington
1996-08-15  0:00                 ` Richard Riehle
1996-08-22  0:00                   ` ++           robin
1996-08-23  0:00                     ` Ken Garlington
1996-08-31  0:00                     ` Ada versus PL/I " Richard Riehle
1996-09-02  0:00                       ` ++           robin
1996-09-02  0:00                         ` Richard A. O'Keefe
1996-09-03  0:00                           ` ++           robin
1996-09-03  0:00                             ` Robb Nebbe
1996-09-17  0:00                             ` shmuel
1996-09-17  0:00                               ` Jay McFadyen
1996-09-18  0:00                                 ` John McCabe
1996-09-20  0:00                               ` shmuel
1996-09-03  0:00                       ` J. Kanze
1996-09-07  0:00                         ` Robert Dewar
1996-09-09  0:00                           ` ++           robin
1996-09-09  0:00                             ` Robert Dewar
1996-09-09  0:00                               ` Ken Garlington
1996-09-03  0:00                       ` ++           robin
1996-09-04  0:00                         ` Robert Dewar
1996-09-07  0:00                           ` ++           robin
1996-09-06  0:00                             ` PL/I or PL/1 Larry Hazel
1996-09-11  0:00                     ` Multiple reasons for failure of Ariane 5 (was: Re: Ariane 5 - not an exception?) J.Worringen
1996-09-12  0:00                       ` Ken Garlington
1996-09-14  0:00                       ` Use DejaNews to retrieve Ariane discussion David Alex Lamb
1996-09-19  0:00                         ` Earl H. Kinmonth
1996-09-14  0:00                       ` Multiple reasons for failure of Ariane 5 (was: Re: Ariane 5 - not an exception?) David Alex Lamb
1996-08-11  0:00               ` ++           robin
     [not found]               ` <4uibvh$References: <Dv45EJ.8r@fsa.bris.ac.uk>
1996-08-16  0:00                 ` A. Grant
1996-08-08  0:00         ` bohn
1996-08-23  0:00   ` Jon S Anthony
1996-08-23  0:00     ` ++           robin
1996-08-23  0:00       ` Richard A. O'Keefe
1996-08-23  0:00         ` Ken Garlington
1996-08-26  0:00         ` ++           robin
1996-08-27  0:00           ` Ken Garlington
1996-08-28  0:00             ` Larry Kilgallen
1996-08-29  0:00               ` Ken Garlington
1996-08-30  0:00             ` ++           robin
1996-08-30  0:00               ` David Weller
1996-09-04  0:00               ` Ken Garlington
1996-09-06  0:00                 ` Sandy McPherson
1996-09-09  0:00                   ` Ken Garlington
1996-08-30  0:00         ` Jon S Anthony
1996-08-26  0:00       ` Ken Garlington
1996-08-26  0:00         ` Dave Jones
1996-08-27  0:00           ` Ken Garlington
1996-08-30  0:00             ` ++           robin
1996-09-04  0:00               ` Ken Garlington
1996-09-06  0:00                 ` ++           robin
1996-09-18  0:00               ` Merlin Dorfman
1996-09-20  0:00                 ` John McCabe
1996-08-30  0:00         ` ++           robin
1996-08-30  0:00           ` John McCabe
1996-09-06  0:00       ` Jon S Anthony
1996-09-06  0:00         ` Robert Dewar
1996-08-23  0:00   ` Jon S Anthony
1996-08-26  0:00     ` ++           robin
1996-07-26  0:00 ` Ariane 5 - not an exception? Bob Gilbert
1996-07-29  0:00   ` Martin Tom Brown
1996-07-30  0:00     ` John McCabe
1996-07-31  0:00       ` Greg Bond
1996-08-03  0:00         ` John McCabe
1996-07-26  0:00 ` ++           robin
1996-07-29  0:00   ` Bill Angel
1996-07-29  0:00     ` Paul_Green
1996-07-30  0:00     ` Richard Shetron
1996-07-30  0:00       ` ++           robin
1996-07-30  0:00     ` Nancy Mead
1996-07-31  0:00       ` Tucker Taft
1996-07-31  0:00       ` Steve O'Neill
1996-08-01  0:00       ` root
1996-08-01  0:00         ` Tucker Taft
1996-07-30  0:00     ` Bob Kurtz
1996-07-30  0:00     ` Ken Garlington
1996-07-30  0:00     ` Lloyd Fischer [this message]
1996-08-04  0:00     ` Richard Riehle
1996-08-05  0:00       ` Fergus Henderson
1996-08-05  0:00       ` John McCabe
1996-08-05  0:00       ` Nigel Tzeng
1996-08-06  0:00         ` John McCabe
1996-08-13  0:00       ` ++           robin
1996-08-13  0:00         ` Ken Garlington
1996-08-13  0:00           ` Kirk Bradley
1996-08-14  0:00             ` Ken Garlington
1996-08-18  0:00           ` PL/I Versus Ada (Was: Arianne ...) Richard Riehle
1996-08-19  0:00             ` Robert Dewar
1996-08-20  0:00             ` Lon Amick
1996-08-21  0:00             ` Tim Dugan
1996-08-21  0:00             ` Lon D. Gowen, Ph.D.
1996-08-21  0:00             ` Tony Konashenok
1996-08-28  0:00               ` Richard Riehle
1996-08-29  0:00                 ` Lon D. Gowen, Ph.D.
1996-08-30  0:00                   ` Tony Konashenok
1996-08-30  0:00                     ` Adam Beneschan
1996-08-30  0:00                 ` John McCabe
1996-08-23  0:00             ` arbuckj
1996-08-22  0:00           ` Ariane 5 - not an exception? ++           robin
1996-08-22  0:00             ` Ken Garlington
1996-08-13  0:00         ` Darren C Davenport
1996-08-14  0:00         ` John McCabe
1996-08-19  0:00           ` Chris Papademetrious
1996-08-22  0:00           ` ++           robin
1996-08-22  0:00             ` John McCabe
1996-08-23  0:00               ` Ken Garlington
1996-08-24  0:00                 ` John McCabe
1996-08-26  0:00                   ` Byron B. Kauffman
1996-08-27  0:00                     ` John McCabe
1996-08-28  0:00                       ` Byron B. Kauffman
1996-08-28  0:00                         ` Robert Dewar
1996-08-29  0:00                           ` Ted Dennison
1996-08-30  0:00                         ` John McCabe
1996-08-22  0:00             ` Martin Tom Brown
1996-08-23  0:00             ` Bob Gilbert
1996-08-24  0:00               ` Robert I. Eachus
1996-08-25  0:00                 ` John McCabe
1996-08-27  0:00                 ` Tom Speer
1996-08-26  0:00               ` Jon S Anthony
1996-08-20  0:00         ` Richard Riehle
1996-07-30  0:00   ` Ken Garlington
1996-08-02  0:00     ` Craig P. Beyers
1996-07-30  0:00   ` Steve O'Neill
1996-07-31  0:00     ` Martin Tom Brown
1996-07-31  0:00       ` Nigel Tzeng
1996-08-02  0:00       ` Ken Garlington
1996-08-03  0:00         ` Thomas Kendelbacher
1996-08-01  0:00     ` ++           robin
1996-08-01  0:00       ` Ken Garlington
1996-08-05  0:00         ` John McCabe
1996-08-06  0:00           ` Ken Garlington
1996-08-06  0:00           ` Ken Garlington
1996-08-06  0:00           ` Mark van Walraven
1996-08-02  0:00       ` Pascal Martin @lone
1996-08-03  0:00         ` Dr. Richard Botting
1996-08-05  0:00           ` system
1996-08-06  0:00         ` ++           robin
1996-08-08  0:00           ` Darius Blasband
1996-08-10  0:00             ` dwnoon
1996-08-12  0:00               ` Thomas Kendelbacher
1996-08-13  0:00                 ` ++           robin
1996-08-13  0:00             ` ++           robin
1996-08-13  0:00             ` Roy Gardiner
1996-08-13  0:00               ` Ken Garlington
1996-08-13  0:00               ` Lance Kibblewhite
1996-08-15  0:00             ` Richard Riehle
1996-08-05  0:00       ` Steve O'Neill
1996-08-06  0:00         ` Frank Manning
1996-08-08  0:00           ` Steve O'Neill
1996-08-09  0:00             ` Pat Rogers
1996-08-09  0:00           ` JP Thornley
1996-08-06  0:00         ` Francis Lipski
1996-08-07  0:00           ` Martin Tom Brown
1996-08-09  0:00             ` Ken Garlington
1996-08-13  0:00         ` ++           robin
1996-08-13  0:00           ` Steve O'Neill
1996-08-01  0:00   ` Jon S Anthony
1996-08-02  0:00   ` James Kanze US/ESC 60/3/141 #40763
1996-08-06  0:00   ` Robert I. Eachus
1996-08-06  0:00   ` Stefan 'Stetson' Skoglund
1996-07-26  0:00 ` Theodore E. Dennison
1996-07-29  0:00   ` Ken Garlington
1996-07-26  0:00 ` JP Thornley
1996-07-29  0:00   ` Ken Garlington
1996-07-29  0:00   ` Nigel Tzeng
1996-07-29  0:00   ` JP Thornley
1996-07-30  0:00   ` Robert I. Eachus
1996-07-31  0:00     ` JP Thornley
1996-08-01  0:00       ` Alan Brain
1996-08-02  0:00         ` JP Thornley
1996-08-01  0:00   ` Ken Garlington
1996-07-27  0:00 ` Bill Angel
1996-07-30  0:00 ` Dr. Richard Botting
1996-07-30  0:00   ` David Weller
1996-07-30  0:00     ` Robert Dewar
  -- strict thread matches above, loose matches on Subject: below --
1996-08-08  0:00 Marin David Condic, 407.796.8997, M/S 731-93
1996-08-09  0:00 ` John McCabe
1996-08-13  0:00 Marin David Condic, 407.796.8997, M/S 731-93
1996-08-15  0:00 ` John McCabe
1996-08-13  0:00 Marin David Condic, 407.796.8997, M/S 731-93
1996-08-15  0:00 ` John McCabe
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