A deadly Amtrak train derailment in Washington state happened because the engineer lost track of where he was on the route and was going more than twice the speed limit when he hit a curve, U.S. safety investigators have found.

The U.S. National Transportation Safety Board announced the findings at a meeting in Washington, D.C. on Tuesday.

The train derailed near the city of DuPont, about 60 kilometres south of Seattle, just before 7:40 a.m. on Dec. 18, 2017. Thirteen train cars spilled off an overpass onto Interstate 5 below, killing three and injuring dozens.

The derailment happened on the train’s first paid passenger run on a new, quicker route from Tacoma, Wash., to Portland, Ore. 

Aerial and ground footage showed the destruction in Pierce County after an Amtrak train en route to Oregon crashed:

Aerial and ground footage show the destruction in Pierce County, south of Seattle, after an Amtrak train en route to Oregon crashed on Monday morning. 0:56

The Tacoma News Tribune reported that investigators also blamed the transit agency Sound Transit for not sufficiently mitigating the danger of the sharp bend; Amtrak for not better training the engineer; Washington State Department of Transportation for not ensuring the route was safe before green-lighting a passenger train; and the Federal Railroad Administration for using rail cars beneath regulatory standards.

“The engineer was set up to fail,” said NTSB chairman Robert Sumwalt.

Investigators said the train was going 78 miles per hour (125 km/h) — way above the 30 miles per hour (48 km/h) speed limit — when it rounded a curve, causing the derailment. (Bettina Hansen/The Seattle Times/AP)

Although federal officials released preliminary findings after the crash, this is the first time investigators have offered a final determination of what happened.

Investigators said the train was going 78 miles per hour (125 km/h) when it rounded the curve. That’s 48 miles per hour (77 km/h) faster than the 30 miles per hour (48 km/h) speed limit.

The engineer appeared to apply the brakes but did not put the brakes in emergency mode.

He told federal officials he was aware of the sharp curve — he’d operated the locomotive three times on that track and observed the route another seven to 10 times — but lost track of where the train was on the route.

More than a dozen cars from an Amtrak train that derailed lie spilled onto Interstate 5 on Dec. 18, 2017. (Bettina Hansen/The Seattle Times via AP)

Seattle-based Sound Transit issued a statement Tuesday afternoon, calling the derailment “a terrible tragedy that sears in the memory of all of us at Sound Transit.”

“While Sound Transit does not operate any service in the segment of track where the accident took place, as owner of the track we commit to closely reviewing the NTSB’s report and implementing recommendations in collaboration with Amtrak, the Washington State Department of Transportation, BNSF and the Federal Railroad Administration,” the agency said.

Amtrak also issued a statement Tuesday.

“We remain deeply saddened by the loss of life and injuries due to this tragic event,” Amtrak said.

The corporation’s statement said it has already implemented a number of changes, including the creation of a new “safety organization” and the development of a strategic plan to “maximize the effective use of simulators in training, qualification and certification of Amtrak employees.”