The recovery of a data recorder may have identified the cause of a fatal derailment of an Amtrak train in Washington state yesterday. NTSB board member Bella Dinh-Zarr tells CBS News that the device reveals that the train took a curve at almost three times faster than its speed limit. “How is it that a train was going 80 miles an hour,” Savannah Guthrie asks, “around a curve where the speed limit was 30?”

Good question:

“That’s one of the things we’re going to be investigating,” NTSB's Bella Dinh-Zarr says when asked why train was going 80 mph in 30 mph zone pic.twitter.com/teGE1nNWVB

— CBS News (@CBSNews) December 19, 2017

AFP and a number of other outlets reported the development this morning as well:

US investigators said an Amtrak passenger train was traveling at more than double the speed limit before it derailed in Washington state, plunging off a bridge onto a busy highway and killing at least three people.

Preliminary information obtained from an event data recorder in the rear locomotive showed the train, which was traveling on a new route for the first time, was speeding at 80 miles (128 kilometers) per hour in a 30 mph zone.

According to ABC News, a system that is supposed to slow trains traveling too fast had been installed but not activated — and the NTSB does not yet know why:

-Positive train control (PTC) was not in use on the tracks where the accident occurred. Though track owner Sound Transit said the feature, which can automatically slow trains in order to avoid danger, was installed it was apparently not activated. NTSB board member Bella Dinh-Zarr said it would investigate why beginning Tuesday. …

-Three people were killed, all were passengers on the train, which was carrying 86 passengers and crew. Several drivers were injured on the road below the crash, but no one was killed.

Expect the PTC system questions to be a major issue with the NTSB and with Congress. Two years ago, a derailment in Philadelphia killed eight passengers when the engineer violated the speed limit on a curve. The PTC system was cited as a way to enhance safety and was supposed to be deployed on existing and especially new lines. The locomotives in this accident had those systems installed, but AFP reports that Amtrak planned to make it functional only after the whole route had been upgraded for higher-speed service. The big question: why not make it functional immediately?

That will also be an issue with local officials, who had tried to warn about the lack of safety systems on this route. One mayor had tried to get Amtrak to delay its launch of the new route, and offered a prescient warning at the time:

In early December, local mayor Don Anderson had warned that more needed to be done to ensure safety on the route.

“Come back when there is that accident, and try to justify not putting in those safety enhancements,” he said at the time, according to KOMO News.

Unfortunately, that turned out to be all too accurate. The NTSB plans to investigate on the ground for at least the next several days while trying to get the recorder from the front recorder, which has been recovered but is apparently giving them difficulty. Investigators hope it will give them more information on how the decision to take the curve at 80 mph was made. They should also ask why a high-speed spur was launched without proper safety systems being operational if this turns out to be accurate. You can bet attorneys will be asking the same questions very very soon.