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Date: Wed, 15 Feb 2012 17:22:18 -0500
From: Alan Browne <alan.bro...@FreelunchVideotron.ca>
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Subject: Re: Positive Train Control
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On 2012-02-14 21:40 , Peter H. Coffin wrote:
> Trains NEVER go anyplace except
> train tracks, so they're pretty predictable.

Or derail.

Or routed onto the wrong track.

Or onto track under maintenance - or washed out or otherwise damaged.

Technology can't solve all problems - but problems of an engineer 
distracted with texting his trainspotters and missing signals is one 
that seems in the realm of the possible.

-- 
"We demand rigidly defined areas of doubt and uncertainty."
Douglas Adams - (Could have been a GPS engineer).