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From: Larry Hazel <lhazel@mindspring.com>
Newsgroups: comp.lang.ada
Subject: Re: software failure question
Date: Sat, 07 Apr 2001 08:41:57 -0500
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Date: 2001-04-07T13:41:54+00:00
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Mark Biggar wrote:
> 
> tmoran@acm.org wrote:
> >
> > Anyone know where this came from?
> > "In one infamous software error, a misplaced minus sign resulted in a
> > fighter jet's control system flipping the aircraft on its back whenever
> > it crossed the equator. "
> 
> It was the fly-by-wire software for the F-16. Fortunately,
> this error was caught in simulation and no planes were actually
> flipped.  For more info, you might want to look in the risks-digest
> report database "http://catless.ncl.ac.uk/Risks".  The bug in question
> can be found easly by searching on "equator".
> 
> --
> Mark Biggar
> mark.a.biggar@home.com

And some errors like this are just simulator related.  Someone had a sign wrong
on the F4J simulator and every time the pilot stepped on the brakes while
rolling, the plane sped up.  Made landings difficult but wasn't very difficult
to find the problem.  

Larry