20092010JMRI DickBronson PaulBender 1 2010-01-01 DB Initial version 2 2010-01-12 PAB Adapted from NYCS-1937 3 2013-07-09 PAB Add aspect mappings 4 2019-03-17 PAB fix image links SLSF Triple searchlight signal with triangle plackard As described in the July 1978 Revision of the St. Louis San Francisco Railway Company publication "RULES for the Maintenance of way and Structures" effective July 1,1973, chapter titled Description of Signals. As noted in the source material, these rules are rules of the Frisco Transportation department. Appearances for a three-searchlight signal head with a triangular placard Clear green red red Rule 281 ../../../resources/icons/smallschematics/aspects/SLSF-1973/SL-3-high/rule281.gif Advance Approach yellow yellow red Rule 282 ../../../resources/icons/smallschematics/aspects/SLSF-1973/SL-3-high/rule282.gif Approach Limited yellow green red Rule 283 ../../../resources/icons/smallschematics/aspects/SLSF-1973/SL-3-high/rule283.gif Approach yellow red red Rule 285 ../../../resources/icons/smallschematics/aspects/SLSF-1973/SL-3-high/rule285.gif Diverging Clear red green red Rule 286 ../../../resources/icons/smallschematics/aspects/SLSF-1973/SL-3-high/rule286.gif Diverging Approach red yellow red Rule 287 ../../../resources/icons/smallschematics/aspects/SLSF-1973/SL-3-high/rule287.gif Restricting red red yellow Rule 288 ../../../resources/icons/smallschematics/aspects/SLSF-1973/SL-3-high/rule288-a.gif Stop red red red Rule 291 ../../../resources/icons/smallschematics/aspects/SLSF-1973/SL-3-high/rule291.gif Stop Stop Stop Approach Stop and Proceed Approach Grade Approach Restricting Approach Diverging Approach Approach Limited Diverging Clear Approach Limited Approach Advance Approach Approach Medium Clear Approach Limited Clear Advance Approach Clear Clear Clear