NEWTON - The Green Line train that rear-ended another Wednesday was speeding, going nearly four times faster than it should have been on that section of track, a federal transportation safety official said yesterday.
A red signal light, which authorities say was functioning at the time of the crash, was a warning to train operator Terrese Edmonds to stop for a minute and then proceed at no more than 10 miles per hour, National Transportation Safety Board member and spokeswoman Kitty Higgins said at a news conference near the crash site.
Instead, investigators say Edmonds's train was racing down the tracks at 37 to 38 miles per hour when it crashed into another train, which had been stopped at a second signal and was traveling at 3 to 4 miles per hour.
"The striking train left at a rate of speed higher than what would have been authorized," Higgins said. "What we don't know yet is why that happened."
The crash, which occurred just before 6 p.m. near a golf course on the D branch of the Green Line, killed 24-year-old Edmonds and sent at least seven people to the hospital.
A rookie with the Massachusetts Bay Transportation Authority, Edmonds had started driving a train part time last October, after taking a seven-week training course, and had recently moved into a full-time position.
Reports that the train operated by the Roxbury woman was speeding came as a shock to her aunt Naomi Crumb, who was in the midst of preparations for her niece's funeral when reached yesterday by phone.
"She drove with my kids; she taught my daughter to drive," Crumb said yesterday afternoon. "I don't care what they say; she was a good, careful driver."
Federal investigators will conduct a "sight distance test" today about the same time the crash occurred, reenacting the path of the accident to determine whether Edmonds's view of the signal was somehow blocked.
"Was there anything that would have prevented the operator from seeing that signal?" Higgins said in a news conference yesterday. "That's part of what we'll be looking at."
Green Line trains are operated manually, with drivers regulating their speed by observing signals along the line.
"It's their responsibility to follow the signals," Higgins said.
Today's tests will begin shortly before 6 p.m. and should last about three hours, NTSB officials said.
Shuttle buses will operate between Newton Highlands and Riverside stations while the tests are being conducted, according to the MBTA website. Normal train service will resume tomorrow morning.
The question of human error is looming larger as investigators rule out other causes.
Testing on the T's signal system concluded just after midnight yesterday morning, and indicated that they were working properly.
Investigators said Friday that there is no evidence Edmonds applied the brakes before the crash.
Brake failure and track flaws have also been ruled out in the crash. Authorities are trying to determine whether cellphone use was a factor.
"We're also obviously looking at if there were any other distractions, including the question of the cellphone," Higgins said. "I don't even know, to be honest with you, if there is a cellphone."
The agency will work with the Middlesex district attorney's office to look at Edmonds's cellphone records, she said.
The office, which is conducting a separate criminal investigation, declined to comment on whether it has Edmonds's cellphone.
Drug and alcohol tests on the three MBTA crew members who survived the crash came back negative.
A toxicology test on Edmonds has not been completed, Higgins said.
In addition, MBTA officials will be asking passengers on the trains to provide federal investigators with accounts of what happened.
MBTA spokeswoman Lydia Rivera said the agency has not determined how they will reach out to the 180 to 200 passengers who were on the trains when the crash occurred.
A funeral for Edmonds will be held tomorrow at Mt. Olive Kingdom Builder's Worship Center in Dorchester, according to Crumb.
Visiting hours will start at 10 a.m. and services will begin at noon.
Tania deLuzuriaga can be reached at email@example.com.