From: eachus@spectre.mitre.org (Robert I. Eachus)
Subject: Re: Fortran or Ada?
Date: 1998/09/23
Date: 1998-09-23T00:00:00+00:00 [thread overview]
Message-ID: <EACHUS.98Sep23153612@spectre.mitre.org> (raw)
In-Reply-To: 6uan3f$7qe$1@nnrp1.dejanews.com
In article <6uan3f$7qe$1@nnrp1.dejanews.com> bglbv@my-dejanews.com writes:
> Also remember that the design and testing methodology often counts for more
> than the language itself. Ariane 501 was lost due to a bug in Ada code.
> (My understanding is that it was an error in the specification; that the
> code happened to be written in Ada was not particularly significant.)
Actually the fact that it was written in Ada did help find the
potential problem. Unfortunately, when it was reviewed in a Ariane 4
context, the potential problem was found, but it was not fixed since
it could "never happen." Physical constraints prevented the problem
from ever occuring in an Ariane 4. The problem was in reusing the
guidance software in the Ariane 5 without changes or review. This can
be seen in the fact that once the bug occurred, the engines deflected
enough to cause the stack to break apart, just like a falling chimney.
So the real problem was that the Ariane 5 was flying with software
whose built in safety limits were set for the Ariane 4. The
particular case that caught them was just the first to materialize.
Remember this the next time someone tells you how wonderful
software reuse is.
--
Robert I. Eachus
with Standard_Disclaimer;
use Standard_Disclaimer;
function Message (Text: in Clever_Ideas) return Better_Ideas is...
next prev parent reply other threads:[~1998-09-23 0:00 UTC|newest]
Thread overview: 96+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <36068E73.F0398C54@meca.polymtl.ca>
1998-09-22 0:00 ` Fortran or Ada? Gisle S{lensminde
1998-09-22 0:00 ` Jeff Templon
1998-09-22 0:00 ` dewarr
1998-09-23 0:00 ` Jeff Templon
1998-09-23 0:00 ` Corey Minyard
1998-09-24 0:00 ` Joel Seidman
1998-09-24 0:00 ` Craig Burley
1998-09-25 0:00 ` dewarr
1998-09-25 0:00 ` Jonathan Guthrie
1998-09-26 0:00 ` Craig Burley
1998-09-26 0:00 ` dewarr
1998-09-26 0:00 ` Craig Burley
1998-09-26 0:00 ` Robert B. Love
1998-09-24 0:00 ` Marc A. Criley
1998-09-24 0:00 ` Jeff Templon
1998-09-25 0:00 ` Dale Stanbrough
1998-09-30 0:00 ` Daniel Barker
1998-09-30 0:00 ` Lawrence Kirby
1998-10-01 0:00 ` Aaron Crane
1998-10-02 0:00 ` Fortran or Ada or gobbledygook? Wes Groleau
1998-10-05 0:00 ` Fortran or Ada? Terry Devine
1998-09-25 0:00 ` dewarr
1998-09-24 0:00 ` dewarr
1998-09-24 0:00 ` Robert I. Eachus
1998-09-24 0:00 ` William Clodius
1998-09-25 0:00 ` dewarr
1998-09-25 0:00 ` dewarr
1998-09-25 0:00 ` Robert I. Eachus
1998-09-25 0:00 ` dewarr
1998-09-25 0:00 ` jbs
1998-09-26 0:00 ` dewarr
1998-09-28 0:00 ` jbs
1998-09-29 0:00 ` Dean F. Sutherland
1998-09-29 0:00 ` William B. Clodius
1998-09-30 0:00 ` jbs
1998-09-30 0:00 ` William Clodius
1998-09-30 0:00 ` dewarr
1998-09-30 0:00 ` jbs
1998-09-30 0:00 ` William Clodius
1998-10-03 0:00 ` Niklas Holsti
1998-10-03 0:00 ` Toon Moene
1998-10-03 0:00 ` Niklas Holsti
1998-10-03 0:00 ` Toon Moene
1998-10-04 0:00 ` Niklas Holsti
1998-10-05 0:00 ` Michel OLAGNON
1998-10-05 0:00 ` Ian St. John
1998-10-05 0:00 ` Richard D Riehle
1998-10-05 0:00 ` dewarr
1998-10-05 0:00 ` dewarr
1998-10-05 0:00 ` Ian St. John
1998-10-06 0:00 ` dewarr
1998-10-06 0:00 ` James Giles
1998-10-06 0:00 ` Mark A Biggar
1998-10-06 0:00 ` James Giles
1998-10-07 0:00 ` dewarr
1998-10-07 0:00 ` dewarr
1998-10-06 0:00 ` Ian St. John
1998-10-08 0:00 ` Gary L. Scott
1998-10-08 0:00 ` Offtopic Airport Diversion (Was: Fortran or Ada?) Harold Stevens ** PLEASE SEE SIG **
1998-10-08 0:00 ` Ian St. John
1998-10-06 0:00 ` Fortran or Ada? Toon Moene
1998-10-06 0:00 ` Jonathan Guthrie
1998-10-06 0:00 ` Michel OLAGNON
1998-10-07 0:00 ` Ian St. John
1998-09-29 0:00 ` Dean F. Sutherland
1998-09-29 0:00 ` Gautier.DeMontmollin
1998-09-29 0:00 ` Dean F. Sutherland
1998-10-02 0:00 ` Geoff Bull
1998-10-02 0:00 ` Robert I. Eachus
1998-10-02 0:00 ` jbs
1998-10-02 0:00 ` William Clodius
1998-10-03 0:00 ` jbs
1998-10-03 0:00 ` Larry Elmore
1998-10-06 0:00 ` Robert I. Eachus
1998-10-06 0:00 ` Pat Rogers
[not found] ` <6udre0$ha1$1@nnrp1.dejane <6utg60$h6l$1@nnrp1.dejanews.com>
1998-10-01 0:00 ` robin_v
1998-09-22 0:00 ` Larry Kilgallen
1998-09-22 0:00 ` Corey Minyard
1998-09-22 0:00 ` Rakesh Malhotra
1998-09-23 0:00 ` Frank Ecke
1998-09-23 0:00 ` bglbv
1998-09-23 0:00 ` Robert I. Eachus [this message]
1998-09-24 0:00 ` Richard D Riehle
1998-09-23 0:00 Marin David Condic, 561.796.8997, M/S 731-96
1998-09-23 0:00 ` Gisle S{lensminde
1998-09-24 0:00 ` John McCabe
1998-09-24 0:00 ` Gisle S{lensminde
1998-09-24 0:00 ` Dean F. Sutherland
1998-09-24 0:00 ` Samuel T. Harris
-- strict thread matches above, loose matches on Subject: below --
1998-09-23 0:00 Marin David Condic, 561.796.8997, M/S 731-96
1998-09-24 0:00 Walt Brainerd
1998-09-25 0:00 ` Robert I. Eachus
1998-09-25 0:00 ` dewarr
1998-10-05 0:00 Condic, Marin D.
1998-10-05 0:00 robin
1998-10-05 0:00 Robert I. Eachus
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