2009 2010 2013 JMRI James Koretsky Ken Cameron Suzie Tall 1 2012-08-31 JK Initial version 1.1 2012-11-06 KSC Added basic aspect mappings 1.2 2013-12-29 ST Split into different mast types and completed mapping BN-1989 Double head searchlight permissive signal As described in the October 1989 Burlington Northern Railroad Southern Region, Nebraska Division Timetable #2. In effect at 0001 Continental Mountain Time, Sunday October 29, 1989. Appearances for a double head smaphore signal mast used in Automatic Block Systems Clear green red Rule 230 ../../../resources/icons/smallschematics/aspects/BN-1989/SL-2-high/rule-230-a.gif Advance Approach yellow green Rule 232 ../../../resources/icons/smallschematics/aspects/BN-1989/SL-2-high/rule-232.gif Approach Diverging yellow yellow Rule 233 ../../../resources/icons/smallschematics/aspects/BN-1989/SL-2-high/rule-233.gif Approach yellow red Rule 236 ../../../resources/icons/smallschematics/aspects/BN-1989/SL-2-high/rule-236-a.gif Diverging Clear red green Rule 237 ../../../resources/icons/smallschematics/aspects/BN-1989/SL-2-high/rule-237.gif Diverging Approach red yellow Rule 239 ../../../resources/icons/smallschematics/aspects/BN-1989/SL-2-high/rule-239.gif Restricted Proceed red red Rule 241 ../../../resources/icons/smallschematics/aspects/BN-1989/SL-2-high/rule-241-f.gif Unlit dark dark - ../../../resources/icons/smallschematics/aspects/BN-1989/SL-2-high/unlit.gif Restricted Proceed Restricted Proceed Restricted Proceed Unlit Clear Clear Diverging Clear Advance Approach Clear Diverging Clear Approach Diverging Clear Diverging Clear Approach Medium Clear Diverging Clear Approach Restricting Clear Diverging Clear Approach Advance Approach Diverging Clear Diverging Clear Approach Diverging Diverging Clear Diverging Approach Medium Approach Diverging Diverging Clear Diverging Approach Advance Approach Diverging Clear Restricted Proceed Approach Diverging Approach Stop Approach Diverging Approach Unlit Approach Diverging Approach