Smooth Running - a Route to Cost Reduction

One of the most important attributes of train running is the capacity to slow or stop. The downside of actually doing so en route between traffic nodes is that transit times are extended and train operating costs are increased. Despite this there does not appear to have been much attention paid to costing the process of slowing or stopping trains. This paper attempts to redress this situation by investigating the cost that would be incurred by a typical freight train as a result of slowing or stopping from otherwise achievable running speeds - hence the title notation of Smooth Running. A range of cost factors were considered and built into a model. The variability of the cost to these factors was then considered, indicating that the significant variables associated with train stopping are train gross mass, normal running speed at the location concerned, and the dwell time when stopped. Similar factors were found to be significant for train slowing (such as for a temporary speed restriction or for a signal check) but with the restricted speed, train length and speed restriction length replacing dwell time. The cost of stopping and re-starting a typical east coast Superfreighter train is estimated to be in the order of $106 , while slowing the same train by as little as 20 km/h from 100 km/h is estimated to cost in the order of $30 with other degrees of slowing being between these two extremes.