Joseph Boardman, chief executive of Amtrak, defended Amtrak's safety record Thursday, even as he lamented that Tuesday's deadly derailment may "have destroyed the confidence of people" who ride the railroad.

He also said Amtrak has been underfunded for decades and must have more money to rebuild the century-old underpinnings of the Northeast Corridor, the nation's busiest rail route.

He said Amtrak officials have not interviewed the engineer of Train 188, who apparently was operating the train at twice the 50-mile-per-hour speed limit entering a sharp curve in Port Richmond.

"We're heartbroken for the families" of the eight people killed and 200 injured in the crash, Boardman said. And he said "we take responsibility for our role in this."

In an interview in a SEPTA building near the crash site, Boardman defended Amtrak's decision not to install "positive train control" yet at the curve. Such a system would have automatically braked the train and prevented the derailment, federal investigators have said.

Boardman said Amtrak had needed to get additional radio-transmitting capability for the system to work in the curve. Now the railroad is aggressively installing the new train control system along the Northeast Corridor and will meet a federal deadline of Dec. 31 for installation, he said.

He said Amtrak still planned to install PTC at the Frankford curve later this year, at the same time as the rest of the corridor between New York and Washington.

"We're the leader in PTC," Boardman said, adding that "with more financing, we could have done it sooner."

He said Amtrak has spent $111 million installing the system so far.

Despite Tuesday's deadly accident, Boardman said, "This is a damn safe's been 28 years since a [fatal] derailment on the Northeast Corridor."

(In 1987, an Amtrak train collided with two Conrail locomotives in a Maryland crash that killed 16 people injured 175.)

"I think that our customers know that this is a safe railroad...but I worry about how this impacts people's idea about riding" Amtrak.

He said he was concerned that the accident may have "destroyed the confidence of people that should not be destroyed."

He said the railroad and its workers will "redouble their efforts in terms of safety and security," and he praised Amtrak workers for "how quickly they stepped in to help passengers" hurt in the crash.

All five crew members on Train 188 survived the crash. Two remain hospitalized, and Boardman said he planned to visit them Thursday.

He also praised the response of Philadelphia emergency workers and city officials.

Boardman, who has spent years lobbying Congress to increase funding for Amtrak, said it was "a frustration" to deal with continuing financial shortages facing the railroad.

"There is a basic problem in that the United States of America has a program of investing in its resources and that has to include the infrastructure....There has to be a breakthrough in how this nation is going to finance its infrastructure."

On Wednesday, less than a day after the fatal crash, the House Appropriations committee voted to slash federal funding for Amtrak.

The legislation, which is now headed for consideration by the full House, would cut Amtrak's total funding from about $1.4 billion last year to $1.14 billion.

Republicans on the committee twice rejected amendments that included more than $1.3 billion in new federal funding for Amtrak spending on capital investments.

"Of course we don't want a reduction," Boardman said. "Nobody in Congress has figured out how to finance infrastructure in this country."