On July 12, at a train station in Brétigny-sur-Orge, a southern suburb of Paris, a passenger train crashed at over 80 mph. The fault was a loose fishplate—the clamp that joins the ends of two lengths of metal rails. The fishplate wriggled out of position, jamming a railroad switch open, which caused the rear of the train to move onto a different track, and an intermediary train car to swing sideways, derailing and killing seven people.
Could this loose fishplate have been caught before the damage was done? Tracks routinely undergo inspection to make sure any breaks, lose parts, or warped rails are caught early. Wear and tear on the tracks (which are subjected to the elements yearlong) is as inevitable as potholes. Pasi Lautala, head of the Rail Transportation Program at Michigan Tech, says traditionally these examinations have been done "by track inspectors, typically driving slowly [in a] truck that runs on the rails, or walking. But it gets easier to miss something if you do it week after week after week."
More and more, railways are relying on "rolling computers," Lautala says, "which may have lasers, radar, ultrasonic inspection, or different types of accelerometers that measure if there are irregularities." These rolling computers can operate either independently on track-bound trucks or be attached to a commercial train to inspect the track while the train is hauling freight or carrying passengers.
In the U.S., some commuter and most freight railroads use a fishplate inspection device made by engineering company ENSCO. Jeff Stevens, ENSCO's business director, says the rolling computer is attached to the end of a freighter, and "has cameras at 45-degree angles, which image the sides of the rail to detect the presence of any anomalies in a fishplate."
Not only is the computer faster and more accurate than the human eye, but it also keeps a record that contains more useful data than simply "broken" or "not broken." "You can also look at trends and degradation over time, and use this information to think forward and create a maintenance plan," Stevens says. Had such a system been employed by the French rail-line, the disaster might have been averted.
On July 24, a commuter train in Santiago de Compostela, Spain, took a sharp corner at approximately twice the 50 mph speed limit. Because of the extreme force of the turn, the train buckled and derailed, killing 79 passengers. The conductor, who had bragged about speeding in the past on his Facebook page, is thought to have lost control while on a high-speed joyride. "What a blast it would be to go parallel with the [Spanish police] and go past them triggering the radar," he previously wrote.
This disaster could have been avoided with technology that already exists. Lautala says there are railway programs that could have stopped the driver from reaching such an unmanageable speed. "There are automated train stop systems," Lautala says. "It will warn the driver of the speed, and if he doesn't react, it'll take over the train." In fact, most European high-speed railways already run with such an oversight program, the European Rail Traffic Management System.
Unfortunately, the Santiago de Compostela commuter train was running on an older system, which monitored only some sections of the track, leaving the driver free to take advantage of the program's blind spots.
One has to wonder: If programs can wrest control from a reckless (or injured) driver, why don't we do away with the human element altogether and have all our trains be computer driven?
Automatic train operation already exists on some local light-rail, subways, and air trains. "But there you're talking about tens or hundreds of miles," Lautala says. "For something like a freight train you're talking about hundreds of thousands of miles." Long-distance freighters also routinely travel through remote dark zones without GPS or other communication capabilities. Lautala argues that automating all our trains is beyond our current infrastructure: "The scale is almost impossible," he says.