Speeding Up Commuter Rail Service; Comparative Actual Performance of Train and Station Platform Designs

Speeding up commuter rail service can be achieved by various design changes in trains or stations or both. An analysis was conducted of the effect of a car design intended to achieve low station dwell times, which are termed short dwell time entranceways (SDE). Actual timetable data from commuter rail systems of different design to estimate the time saving from using SDEs compared with traditional end vestibule entranceways (EVE) were used. A new procedure was developed to characterize speed (or run time) performance of trains that accounts for differences among run characteristics (e.g., station spacing, speed limits). The validity of the procedure is assessed, and its usefulness as a complement to train performance simulators is discussed. The lines analyzed had speed limits averaging 60 mph (96.6 km/h) and average station stop spacings of 1.25 mi (2.01 km) to 5.0 mi (8.04 km). The time saving resulting from SDEs versus EVEs at low-level platforms is slightly more than 5% at the shortest station spacing, about 2% at the longest. These gains approximate those from electrification retaining the EVE car design. Thus, car design to achieve low dwell time is a very important option. Because EVE car designs are most prevalent on lines with a mixture of high- and lowlevel platforms, the implications for such lines, including Americans with Disabilities Act accessibility considerations, are discussed.