To Cuomo, the scene "looked like a toy train set that was mangled by some super-powerful force," the governor said in a phone interview with CNN.
As deadly as the derailment was, the toll could have been far greater had it happened on a weekday, or had the lead car plunged into the water instead of nearing it. The train was about half-full at the time of the crash, rail officials said.
"On a workday, fully occupied, it would have been a tremendous disaster," New York City Fire Commissioner Salvatore Joseph Cassano told reporters at the scene. The affected line, called the Hudson line, carries about 18,000 people on an average weekday morning.
For decades, the NTSB has been urging railroads to install technology that can stop derailing caused by excessive speed, along with other problems.
A rail-safety law passed by Congress in 2008 gave commuter and freight railroads until the end of 2015 to install the systems, known as positive train control. Aimed at preventing human error — the cause of about 40 percent of train accidents — it can also prevent trains from colliding, entering tracks undergoing maintenance or going the wrong way because of a switching mistake.
But the systems are expensive and complicated. Railroads are trying to push back the installation deadline another five to seven years.
Metro-North is in the process of installing the technology. It now has what's called an "automatic train control" signal system, which automatically applies the brakes if an engineer fails to respond to an alert that indicates the speed is excessive.
Such systems can slow trains in some circumstances but not bring them to a halt, said Grady Cothen, a former Federal Railroad Administration safety official.
Sunday's accident came six months after an eastbound train derailed in Bridgeport, Conn., and was struck by a westbound train. The crash injured 73 passengers, two engineers and a conductor. In July, a freight train full of garbage derailed on the same Metro-North line near the site of Sunday's wreckage.
"Safety is clearly a problem on this stretch of track," state Sen. Jeff Klein, who represents the nearby area, said Sunday.
Earlier this month, Metro-North's chief engineer, Robert Puciloski, told members of the NTSB investigating the Bridgeport derailment and that the railroad is "behind in several areas," including a five-year schedule of cyclical maintenance that had not been conducted in the area of the Bridgeport derailment since 2005.
The NTSB issued an urgent recommendation that Metro-North use "redundant protection," such as a procedure known as "shunting," in which crews attach a device to the rail in a work zone alerting the dispatcher to inform approaching trains to stop.
Associated Press writers Kiley Armstrong, Colleen Long, Jake Pearson and Jennifer Peltz in New York, Joan Lowy in Washington and Stephen Singer in Hartford, Conn., contributed to this report.
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