By Paul Nussbaum

An electronic train-control system designed to prevent the kind of accident that killed at least seven people Tuesday was not in place where Amtrak Train 188 crashed, as it was entering one of the sharpest curves on the Northeast Corridor.

To prevent such accidents, Amtrak crews have been installing an "Advanced Civil Speed Enforcement System" on the Northeast Corridor and other Amtrak routes, and they were to install the system this year in the Philadelphia area.

Had such a system been in place at Frankford Junction, Tuesday's accident would not have occurred, Robert Sumwalt, board member of the National Transportation Safety Board said Wednesday.

The system is designed to automatically slow speeding trains, prevent collisions between trains, and enforce speed restrictions. With the system, an onboard computer activates a train's brakes if the engineer doesn't.

Positive Train Control, which includes Amtrak's system, is required by federal law to be installed on all passenger and major freight railroads by the end of this year.

But many railroads have asked for more time to install the expensive systems, and Congress is considering extending the deadline to 2020.

Without positive train control, "everybody on a train is one human error away from an accident," the National Transportation Safety Board said last year in renewing its call for quick installation of PTC.

"Each death, each injury, and each accident that PTC could have prevented, testifies to the vital importance of implementing PTC now," the NTSB said. It has made PTC one of its "most wanted" safety improvements.

On much of the Amtrak network, including Tuesday's crash area, Amtrak relies on "automatic train control," an older system which establishes safe braking distances but does not control speeds as precisely as positive train control.

The death toll from Tuesday's crash was expected to rise as emergency workers continued to search Wednesday for bodies in the mangled wreckage of the seven-car train.

The train's engineer, who has not been identified, declined to give a statement to police investigators and left the East Detectives Division with an attorney, police commissioner Charles H. Ramsey said Wednesday.

The train's conductor, also unidentified, was at Einstein Medical Center Philadelphia with a skull fracuture, Ramsey said.

The train was traveling 106 m.p.h. when it approached the curve, the National Transportation Safety Board said after recovering the train's locomotive event data recorder, which includes a speed recorder. The train slowed to 102 mph before it crashed.

Congress acted to require positive train control after a 2008 collision in Chatsworth, Calif., in which a Metrolink commuter train collided head-on with a Union Pacific freight train, killing 25 and injuring more than 100.

Investigators found the engineer of the Metrolink train was texting and ran past a red stop signal and crashed into the oncoming freight train.

Amtrak said earlier this year it hoped to have PTC in place on the corridor by the end of this year.

Currently, the system is operational on the corridor between Boston and New Haven, Conn.; New Brunswick and Trenton, and Perryville, Md. and Wilmington.

In the Philadelphia area, SEPTA is spending more than $300 million to install PTC on its commuter rail network, and the transit agency expects to meet the federal year-end deadline, deputy general manager Jeffrey Knueppel said Wednesday.

"We put this as our highest priority," Knueppel said. "We've moved ahead as fast as we could do this."

"This has pushed our entire industry to the has been a huge, huge challenge."

U.S. Sen. Pat Toomey, (R., Pa.), who went to the accident scene Wednesday, declined to say if he would support a delay in requiring PTC.

"I want to understand what we have now, what it's capable of, and what the alternative would accomplish for us," Toomey said.

Tuesday's Amtrak crash accident happened at a sharp curve in Frankford where several rail lines merge. Trains are restricted to 50 miles per hour there.

The speeding Train 188 failed to make the turn and derailed, scattering its locomotive and cars across the tracks of the Northeast Corridor and a freight line that carries trains to the Delair Bridge over the Delaware River.

The locomotive was the first of the new "Cities Sprinter" models that were put in service just last year, amid much fanfare and a visit to Philadelphia by Vice President Biden.

Tuesday's accident halted Amtrak service between Philadelphia and New York City, as well as SEPTA commuter rail service on its Trenton line.

It may be a week before the SEPTA service resumes, officials said Wednesday, while Amtrak service may be restored more quickly.

Police also are investigating two bizarre incidents involving projectiles hitting an Amtrak and a SEPTA train in the minutes before Tuesday's deadly derailment, in the same corridor as the accident.

Amtrak Acela Train 2173, enroute from New York, was struck by a rock or other object in North Philadelphia at about 9:05 p.m. SEPTA train 769, enroute to Trenton, was struck by a projectile at about 9:10 p.m. near the North Philadelphia station, breaking the engineer's window.

Officials said neither incident appeared to have any connection to the deadly derailment that happened at about 9:30 p.m.

Inquirer staff writer Mike Newall contributed to this article.

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