After another fatal Amtrak train crash Sunday — the fourth since December — safety advocates and federal investigators are again expressing concern about the slow pace of railroads installing and implementing technology that could prevent some train collisions.

Some are also raising questions about what they contend is a “lax safety culture” at Amtrak, which has now had four fatal train accidents in less than two months’ time.

National Transportation Safety Board investigators are on the scene of Sunday’s wreck in Cayce, S.C., trying to figure out why Amtrak train #91 traveling south from New York City to Miami was diverted onto a side track early Sunday morning where it collided head on with a parked freight train at about 2:45 a.m. ET, killing two crew members and injuring more than 100 passengers.

NSTB Board Chairman Robert Sumwalt says a switch on the track had been manually padlocked into a position that steered the Amtrak train from the main southbound line track onto a side track, where the CSX train was parked.

Amtrak’s CEO is wasting time no time in placing the blame on CSX, which owns, operates and controls the tracks Amtrak uses in the area.

Reuters is reporting that in an email message to staff Sunday night, Amtrak President and CEO Richard Anderson said the passenger train was “on the track as dispatched by CSX, the host railroad… our crew on 91 was cleared to proceed by CSX dispatch, but CSX had lined and padlocked the switch off the mainline to the siding, causing the collision.”

Regardless of why the train was sent onto the wrong track, Sumwalt says a automatic, GPS-based safety system called Positive Train Control, would have likely kept the two trains from colliding, had it been installed and implemented.

“An operational PTC system is designed to prevent this kind of accident,” said Sumwalt at a media briefing Sunday night.

Back in November, at an NTSB meeting to announce the results of the investigation into a fatal Amtrak crash in April of 2016 outside of Philadelphia, Chairman Sumwalt blasted the railroad for its “lax” attitude toward safety, saying “Amtrak’s safety culture is failing, and is primed to fail again.”

That warning seems prophetic now, as there have been four deadly Amtrak accidents in less that two months time.

Last Wednesday, an Amtrak train carrying Republican members of Congress to a retreat in West Virginia hit a garbage truck in a crossing near Charlottesville, Va., killing one person on the truck. A North Carolina couple was killed Jan. 14 when their SUV was hit by an Amtrak train. Police say it appeared the driver of the SUV tried to go around lowered crossing gates. And on Dec. 16, 2017, an Amtrak train making it’s inaugural run down a new route between Seattle and Portland derailed as it entered a curve on a highway overpass speeding along at more than 50 MPH above the posted speed limit. The engineer in that crash says he did not see a key milepost nor a signal warning to a speed reduction shortly before the crash.

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