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Wed Jul 5 11:49:40 EDT 2017

Somewhere I have seen something to the effect that in steam days the signal block in approach to a wayside signal was extended beyond the signal a distance sufficient to insure that the cab of a steam locomotive would be beyond the signal before the signal changed to "stop."  This was to insure that a distracted engineer would not look up at the last second, see the newly set stop aspect and, being confused,  throw the train into emergency.

Maybe this practice also applied to the early diesel days on the N&W when the long hood end of the diesel locomotive was designated as "front."

Gordon Hamilton
  ----- Original Message ----- 
  From: NW Mailing List 
  To: NW Mailing List 
  Sent: Tuesday, July 04, 2017 10:45 AM
  Subject: Re: Signals

  Bruce hit the nail on the head. Also of note after a track is shunted it takes several seconds for it to change aspect. I've always known it took a little bit but didn't know how much until after I deadheaded by train the other night. At 50 MPH the signal would still be showing clear when we went by it on the 2nd engine. At 25 MPH it would change roughly about the time my window would get to it on the second engine. So likely dependent on the speed of the pusher set the aspect probably just hasn't changed yet.


  On 6/29/2017 14:29, NW Mailing List wrote:

    On Thu, Jun 29, 2017 at 3:23 PM, Carl wrote:

      Can somebody explain this:

      How can the signal be green when a train is coming?

    ​Per the caption, the train isn't coming, it is a pusher set going away. It is problaby a combination of the telephoto lens and the actual location of the engines that makes this look odd, but more than likely the helpers haven't yet passed the point on the track that will trigger the signal to drop to red.

    Bruce in Blacksburg


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Nathan Simmons
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