The big picture: today's computer-aided dispatch systems provide networkwide visibility so railroads can manage traffic proactively—maximizing capacity and increasing productivity

Railway Age, Nov, 2004 by Marybeth Luczak

Imagine the ability to control thousands of track miles from a single location. Imagine a system that offers rail dispatchers a dynamic display of all territory and automates features such as meets and passes, train tracking, routing, route stacking, train sheet, and train status line-up. Imagine combining CTC (Centralized Traffic Control) and DTC (Dark Territory Control), and having backup capabilities that allow dispatch from multiple locations in the event of an emergency. Imagine managing capacity constraints and increasing productivity with the click of a mouse. All of this is possible with today's computer-aided dispatch (CAD) systems from suppliers like Alstom, Advanced Railway Concepts, Digital Concepts, GE Transportation, Siemens, and Union Switch & Signal.

"What railroads are trying to do now is squeeze every last ounce of benefit from their existing infrastructure," says Dale Roddy, president of DigiCon. "Using a CAD system that lets dispatchers spend less time doing clerical work and more time focusing on traffic and problem areas and provides maintenance-of-way workers with planning tools that allow them to work around revenue service trains multiplies the effectiveness of the infrastructure." The bottom line: CAD systems' movement planners can increase average train velocity by 2-3 mph, translating into a savings of $50-$100 million a year for every 1 mph of improvement, says Hasan Dandashly, general manager-Train Management Systems for GE Transportation. The technology also helps reduce re-crews by 20-50%.

"CAD systems act as a railway central nervous system," says Charley Best, vice president sales and marketing for AR Concepts. These distributcd systems replace disparate control technologies and integrate office and field data to provide real-time, networkwide visibility.

Transit properties were among the first to implement them. "On the transit side, there is a tremendous degree of subsystem integration already," says Jack Wall, manager-systems sales for US&S. "Traction power status is on the same display as signal and ventilation system information, so if there is a tunnel fire, dispatchers are able to see the train location relative to the fire and better respond."

Automation is key to CAD system efficiency. Such routine functions as controlling signals and switches, generating ETAs, and managing basic entry, and exit of certain routes are handled automatically. Built-in alerts inform dispatchers if there is a special bulletin on speed restrictions and/or track-work in an area they're trying to move trains through so they can consider alternatives.

One of the latest CAD features is movement planning, which optimizes movements across a railroad--not just in a single division or individual dispatcher's territory.

"Traditionally, when a train is dispatched from say Chicago to Atlanta, it's passed from dispatcher to dispatcher, and if there is congestion in the fourth dispatcher's territory, the first dispatcher wouldn't necessarily know it--unless it was caused by a hurricane or other major event," explains John Samuels, senior vice president-operations planning and support at Norfolk Southern. But today's CAD systems have changed that. Now every dispatcher can see where the bottlenecks are earlier, so trains can be rerouted. And by using train schedules, real-time operational factors, and dispatcher and terminal manager input, the CAD systems can create movement plans for dispatchers to implement.

Some railroads are taking this one step further. NS, which has been developing its new system with GE for the past six years, will have a movement planner that anticipates problem areas, generates new traffic plans every hour, and executes them (RA, March, p. 29). To do this, NS has set all train attributes--including priority level and delay costs--based on its business objectives so the system can look over the network and make decisions. Because anomalies occur, the planner is able to make changes, as needed. (The system was expected to begin operating in Atlanta this month, with full implementation between 2005 and 2006.)

Not every railroad is ready to give up the reigns to a computer system. "There are contradicting opinions: One, the control system should be controlling the railroad by itself and a dispatcher becomes an overseer, and the other where the dispatcher is the centerpiece of decision-making. He is presented with all information and combines it with his experience to execute a plan," says Eckart Thies, manager-Operations Control Systems for Siemens. "Not only is [the former] a capital investment, the railroad must input and maintain all the parameters allowing system decision-making."

Among the other features that railroads and transit properties should consider when selecting a CAD system:

* M-o-w authority. Electronic m-o-w authority offers safety and productivity, benefits, according to DigiCon's Roddy. Authority limits can be communicated to field-vehicle laptops. The vehicles are tracked by GPS, and when they move out of limits, operators are alerted. Electronic TWC authorities also reduce field-dispatch communications, since track inspectors can view dispatcher screens for planning purposes. "They don't have to wait in the radio queue to find out where they can go to work for the day," explains Roddy. "Instead, they can get a sense of the day's traffic flow, look for holes, and send an informed request for authority via 'instant messaging.' We've found that this saves upwards of 20 minutes on each authority."