Wednesday, July 13, 2011

1. Keystone West - Pittsburgh to East Liberty

This description of the railroad line is based upon the track charts that describe gradient, curvature and speed and the NS Employee Timetable. The designated mile point for the Pittsburgh Amtrak Station is 353.2 (40.445089N79.991806W). The mileposts will have lower numbers as the line is traced east. The curve at the concourse of the station is a 10.5 degree curve. With maximum rail elevation a 10.5 degree curve is capable of a 35 mph speed. The actual speed limit is 15 mph as elevating the outside rail beyond its 1.0 inch would make entry and exit of passenger equipment impractical.

The blue line is the existing NS line.

(The Federal Railroad Track Safety Standards can be found at 49 CFR 213.57. Appendix A found there is a chart indicating speeds for curves.)

At 352.5 the freight speed is increased to 30 mph to and through East Liberty 348.8 (40.459508N79.923272W).

The NS passenger speed from 352.5 to 352 is 30 mph. 352 to 351 is 40 mph. 351 to 350 is 35 mph. Then from 350 to 348.4 at East Liberty the passenger speed is 40 mph.

Data available for PRR operations indicates that through the station as now the speed was 15 mph. At 23rd Street 40 mph was permitted. At 28th Street 45 mph was permitted. 50mph was permitted at the Bloomfield Bridge. The curve at East Liberty required 40 mph on track 1, 45 mph for tracks 2 and 3.

The line between Pittsburgh and East Liberty has 13 curves within some 5 miles. Given the topography and urban environment, line enhancements are impractical.

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