Two Amtrak maintenance workers were killed Sunday when a passenger train bound for Washington plowed into a backhoe machine they were operating just south of Philadelphia.
The train's engine derailed but remained upright, as the crash tossed about passengers in the two adjacent cars, sending 30 people and the train's engineer to hospitals with minor injuries. It was the second Amtrak derailment in a little more than three weeks, coming after a midnight wreck in southwest Kansas that injured 32 passengers.
Sunday's derailment occurred minutes after Amtrak's Palmetto train, with 330 passengers and seven crew members, departed Philadelphia's 30th Street Station at 7:32 a.m. and gathered speed as it began to pass through Chester, Pa., about 18 minutes later.
Investigators from the National Transportation Safety Board and Federal Railroad Administration will want to know whether the train was on the correct track. If it was, they will turn to why crews using the rail-mounted backhoe machine were on what's known as a "live" track.
The two workers, who were not identified Sunday, were the third and fourth Amtrak employees killed since 2000. Only 18 passengers have died in that period, eight of them in a 2015 wreck in Philadelphia. One of the two people was the operator of the backhoe, an NTSB spokesman said. The second person was reportedly the supervisor of the maintenance work.
The NTSB will remove the event data recorder and video from forward and inward facing cameras mounted in the engine cab, sending them to Washington for analysis.
"We will be looking at mechanical, operations, signal, track, human performance and survival factors," said Ryan Frigo, the NTSB's lead investigator. Frigo was unable to fully describe the size of the backhoe beyond "a piece of heavy equipment," but it crushed in the front of the locomotive and created a spider-web pattern in the cab's shatter-proof front window.
Amtrak shut down service between Philadelphia and Wilmington for much of the day, resuming limited service by mid-afternoon Sunday. The disruption caused havoc for travelers.
The derailment was about 25 miles from the North Philadelphia location where a May 2015 derailment killed eight and injured more than 200.