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From: roma@uiucuxc.CSO.UIUC.EDU
Newsgroups: net.railroad
Subject: Re: Forwarding: Re: Signaling on the NY
Message-ID: <16900012@uiucuxc>
Date: Thu, 16-Jan-86 02:26:00 EST
Article-I.D.: uiucuxc.16900012
Posted: Thu Jan 16 02:26:00 1986
Date-Received: Tue, 21-Jan-86 07:01:55 EST
References: <1083@brl-tgr.ARPA>
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Nf-ID: #R:brl-tgr.ARPA:1083:uiucuxc:16900012:000:2074
Nf-From: uiucuxc.CSO.UIUC.EDU!roma    Jan 16 01:26:00 1986


In a previous note, dennis@CSNET-SH.ARPA writes:
> 
> 	> Chicago's rapid transit lines (CTA) have several stretches that
> 	> have road crossings at grade.  They are on the Evanston,
> 	> Skokie, Ravenswood, and Douglas lines.  
> 
> Are these lines third rail or overhead?  I would think that the dead spot in
> the third rail and easy public access to the third rail would rule out grade
> crossings, unless all the cars were electrically connected for power...

Also, Chuck.Weinstock@a.sei.cmu.edu writes:

> At least some of the CTA system with grade crossings is third rail.  If I'm
> not mistaken the Skokie Swift is for sure.  The Linden Avenue line used to
> be overhead, but if my memory serves me correctly has since become third
> rail.  

The *only* CTA line using overhead is the Skokie Swift line, on which there
are several grade crossings.  (The east end of the Skokie Swift is third rail
powered, but it is grade separated.)  The remaining CTA lines are wholly powered
by third rail.  When at ground level, the tracks are fenced off to discourage
trespassing.  Grade crossings are equipped with 'cattle guards'.
The single crossing on the Evanston line to Linden Avenue does have the strange
'rotating' fences.  This line was converted from overhead to third rail
sometime in the last decade or so; I guess the special fences were put up
because of the danger to people not aware of the change to third rail.

All CTA trains (except for some on the Evanston and Skokie branches) operate
in semi-permanently coupled pairs with a cab on each end.  Furthermore,
the couplers that join multiple pairs of cars together (to up to 8 cars) 
are equipped with air and electrical connections.  Thus, the cars have no
problem with the third rail gaps necessitated by road crossings.  (Even a single
pair of cars is long enough to span the gap without coasting, I believe.)

Jon Roma
Computing Services Office, University of Illinois at Urbana-Champaign

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