Investigators said Tuesday a fatal Boston trolley crash in May 2008 could have been prevented if an automated train control system had been in place.
Trolley operator Terrese Edmonds, 24, died after her train sped through a red stop signal and rammed another in a crash in suburban Newton, Mass., that also injured seven passengers on the Massachusetts Bay Transportation Authority's Green Line.
At a National Transportation Safety Board meeting Tuesday to analyze the crash, acting Chairman Mark V. Rosenker said if such an automatic braking system had been implemented, "I don't believe we'd be here discussing this today."
Rosenker noted that other MBTA lines had such systems.
"If technology exists and it exists on the other lines, why would the Green Line not have everything possible that is going to prevent the accidents from happening?" Rosenker said.
Investigators estimated the striking trolley was moving at 38 mph at impact, and they said Edmonds apparently ignored the signal, which had been stuck in the stop position.
The trolley struck from behind had stopped at a second malfunctioning red signal. Investigators found broken electrical connections between track sections, interrupting the signal that would have made the signal lights go on and off correctly.
Operators were not required to report faulty signals by the MBTA, a factor that likely contributed to the accident, investigators said.
"This could lead to a great safety risk," investigator Jeff Leaman told the panel.
In May, a second Green Line trolley collision in Boston on May 8 was blamed on a text-messaging driver. Operator Aiden Quinn, 24, was indicted last week on charges of grossly negligent operation in the crash that injured more than 50 people.
Both crashes prompted talk of an automatic braking system, but that talk has been muted since nine people died last month in the crash of a Washington Metro train that had been running on automatic. The system apparently malfunctioned.
The May 2008 crash damage was estimated at $8.6 million by investigators. An estimated 185 to 200 passengers were on the two trains at the time of the crash.
Investigators also told the panel testing showed no illegal drugs or alcohol were detected in the operator's system when she died.
Testing showed the presence of Doxylamine - which is used in over-the-counter sleeping aids - in Edmonds' urine. Investigators did not say in their report submitted to the safety panel whether they believed that was a factor in the crash.
This program aired on July 14, 2009. The audio for this program is not available.