This document was requested by T. Raslear of the Federal Rail Administration (FRA) on 3/3/99 of the PTC Human Factors Team in conjunction with ongoing discussions of PTC standards. The charge was to investigate the "reliance effect" and the "distraction effect," where definition and focus were left to the authors.

With regard to future automation of railway systems, and in particular with regard to the implementation of Positive Train Control (PTC), questions have been raised about the possible propensity for a locomotive engineer (LE) or conductor (C) to become over-reliant on automation and/or to become distracted by the additional monitoring burdens required by the automation, and for these effects to compromise the performance of their duties and for safe and efficient train operation.