Simple Switching Maneuver Somehow Went Badly Awry

Witnesses at the site of the wreckage of a Marc train and an Amtrak train.
(Michael Williamson/The Washington Post)

As the dead and injured were removed from the collision of Amtrak's Capitol Limited and MARC commuter train 286, something became painfully clear to the officials who first walked the smoky scene: The MARC train was somewhere it shouldn't have been.

The commuter train should have stopped at a signal several hundred feet from the point of impact, but instead struck the side of the Amtrak locomotives as the Capitol Limited moved through a switch to cross over to an adjacent track.

The location of the wreck raises the probability that the MARC train ran a stop signal, but it does not explain why. Was there a mechanical problem with the train? Was there a defect in the signal? Or did the engineer simply roll through it because of fatigue or some other human factor?

Mort Downey, deputy transportation secretary, said the crash took place at least "a couple of car lengths beyond the signal." Asked if it appeared the train had run a stop signal, Downey said: "It certainly looks like that happened. It's hard to say he was back where he should have been."

The collision happened during a routine mainline switching maneuver that occurs thousands of times a day on railroads nationwide.

At the accident site, there are two mainline tracks, owned by CSX Transportation Co. Amtrak and MARC operate over the tracks under a contract with CSX, and all switches and signals in the area are controlled by a CSX dispatcher in a large, heavily reinforced concrete room in Jacksonville, Fla., with large lighted maps of the CSX rail system covering the wall.

Trains may run in either direction on either track at Silver Spring, protected by signals that remain red until the dispatcher clears a train to pass. As a safety backup, the signal cannot be cleared if a train is in the stretch of track ahead.

Railroad sources said the Amtrak train was running on track No. 2 -- the southernmost track and the same track that the MARC train occupied coming in the opposite direction -- because a freight train was blocking track No. 1. The Amtrak train, in a routine maneuver, was set up by the dispatcher to go through two switches that form a crossover between the two tracks.

Under normal circumstances, the MARC train would have received a red signal to stop short and allow the Capitol Limited to cross over to track No. 1. The dispatcher, using a computer keyboard, would have then changed the switches to allow the MARC train to continue east toward Washington, giving the train a green signal.

The switching move is much like cars passing on a two-lane road, but with the added protection of signals -- colored lights on high poles next to the track -- that are designed to prevent them from colliding.

However, engineers must remain alert to the signals. The CSX line does not have an "automatic train stop" system that would automatically apply the brakes if a train ran past a restrictive signal. Typically, engineers are warned they are approaching a stop signal a mile or more ahead by a yellow "approach signal."

A number of things could have gone wrong to cause the derailment, including the possibility that the MARC train ran through the stop signal. Investigators will look carefully at the train's braking system to determine if it developed a problem, just as two U.S. freight trains developed air brake problems and wrecked on heavy grades within the last three months. They also will check to determine whether the signal system was operating properly; on rare occasions, signal systems have been known to give "false positive" indications.

A scene from the accident site.
(Nancy Andrews/The Washington Post)

Investigators also will determine exactly where each train derailed. It is possible that one or the other train derailed and crashed into the other.

Once investigators determine exactly what happened, they will begin the hard questions. Numerous issues are raised by this wreck:

Train crew fatigue. Investigators for the National Transportation Safety Board will carefully review the last 24 hours of the train crews' lives to determine whether they were impaired by lack of sleep. Drug and alcohol tests are standard.

Passenger car integrity. U.S. passenger cars are among the most sturdy in the world, but the safety board has recommended installation of even stronger "crash posts" in passenger cars, particularly when they are being used in "push-pull" service, as was the case with the MARC train.

Crash-proof locomotive fuel tanks. Investigators will want to determine why locomotive fuel tanks apparently ruptured and fed a large fire. The lead Amtrak locomotive of two was a new design General Electric engine with "crash-proof" fuel tanks.

Positive train separation. Only in a few places, such as Amtrak's high-speed Washington-Boston route, do railroads use systems that automatically stop a train that runs through a restrictive signal. The safety board for years has called for installation of a modern system nationwide that would take control of the train away from an engineer and bring it to a smooth stop if the engineer was incapacitated or ignored signals.

However, the railroad industry has been reluctant to embrace the expensive technology. The Union Pacific and Burlington Northern-Santa Fe railroads are preparing to install a test system on a line from Seattle to Portland that the two railroads share. That line was the scene of a spectacular head-on collision several years ago between two freight trains.

The Amtrak wreck could not have come at a worse time for the railroad industry, already under increased scrutiny because of a collision between two commuter trains in New Jersey earlier this month as well as two runaway freight trains. Those incidents left two dead and 10 injured.

Each of the freight trains -- one at St. Paul, Minn., on Wednesday and the other in California's Cajon Pass on Feb. 1 -- involved air brake failures because of a blockage in the air brake line. Special radio-controlled brake valves are now being produced that would have prevented both wrecks by allowing engineers to apply brakes from the rear of the train.

Congress is scheduling hearings on rail safety because of the other wrecks, beginning with a March 5 House hearing, and Federal Railroad Administrator Jolene Molitoris said her agency will speed a rule-making procedure on the end-of-train device.