NetNews Usenet Archive 1993 #1/NN_1993_1.iso/spool/comp/org/eff/talk/8338

Internet Message Format | 1993-01-06 | 1.7 KB

Path: sparky!uunet!spool.mu.edu!uwm.edu!rutgers!sgigate!sgi!wdl1!wdl39!mab
From: [e-mail] (Mark A Biggar)
Newsgroups: comp.org.eff.talk
Subject: Re: Software as PE
Message-ID: <[e-mail]>
Date: 5 Jan 93 23:31:26 GMT
References: <[e-mail]> <[e-mail]> <[e-mail]>
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Organization: Loral Western Development Labs
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In article <[e-mail]> [e-mail] (Pete Hardie) writes:
>In article <[e-mail]> [e-mail] writes:
>>        It was a software engineer who decided that the brakes on the
>>        Fokker 100 shouldn't operate if a sensor indicated the wheels
>>        were up. They were designated part of the "on the ground"
>>        module. An aircraft systems engineer would have understood the
>>        difference between the sensor and the fact, recognised that
>>        applying brakes in midair could do no harm, and saved a few
>>        pilots a change of underwear.
>First of all, is this a confirmed thing?
>Secondly, just to clarify:  is the problem here that a sensor failed, thus
>preventing the brakes from operating when the wheels were in fact down?

It is my understanding that the decision of the software engineer was the
CORRECT one.  On a large jet aricraft the wheel brakes MUST NOT be applied
until after the wheels are on the ground and rolling because there is too
much chance of blow-out on touchdown otherwise.  The real problem was that
there was no emeregecy override in case the weight-on-wheels sensor failed.

--
Mark Biggar
[e-mail]