From: joekor@earthlink.net   
      
   On 3/26/2016 10:05 AM, Jishnu Mukerji wrote:   
   > On 3/18/2016 11:16 AM, Joseph D. Korman wrote:   
   >>   
   >> Because of careless train operators over 30 years ago, the TO must call   
   >> the command center to get permission to key by.  Most signals, with the   
   >> latest round of upgrading, the signal block begins a few feet in front   
   >> of the stop arm, so the train need only stop and proceed slowly to the   
   >> arm to lower.  There might be some that still need to have a button   
   >> pressed the make the arm lower.   
   >>   
   >>   
   >   
   > I can't remember the details, but I seem to recall that when a home   
   > signal is fleeted there is a special indication lamp on the signal which   
   > converts it from an absolute stop to a stop and proceed, only for the   
   > duration that the indication is lit. For the life of me I can't find the   
   > details, but I have seen this happen on the NEC. Then again I may be   
   > remembering wrong about the indication. Maybe they talk to the   
   > dispatcher each time this happens.   
   >   
      
   That may be on the NEC, but it's not on the NY subway, that I know of.   
   A R/R home signal is stop and stay.  R/R/W is a call on.  Fleeting is   
   available at some locations, but at some locations (eg, 135th-145th on   
   8th Ave) it's the opposite (though this may have changed).   
      
   Every train on at least the express tracks northbound causes the signal   
   to stay R/R until the tower normals it and clears it with or without   
   throwing the switch.  This insures that the tower can't leave the signal   
   clear inadvertently for the next train.   
      
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