"What causes us concern the most is the fact that this was not supposed to happen," Jackie Jeter, president of Amalgamated Transit Union Local 689 said Tuesday. "There are safety mechanisms that are on place on the trains to prevent this type of accident. And, for me, as president of the union and as a train operator, I have to wonder why didn't those safety mechanisms kick in and prevent it."
Train recorders will provide insight into what happened as the information is evaluated over the next few days, former National Transportation Safety Board investigator Barry Sweedler said. The train that was hit had several recorders on it, but the one that collided into it didn't have any.
The victims of Monday's train crash ran the gamut from a young mother of two and a military officer to a man on the way to his night shift and a 59-year-old woman who was making plans for the trip of a lifetime.
The military officer killed in the crash was Major General David F. Wherley Jr., who died alongside his wife, Ann. Both were 62. Wherley, a career military man had recently retired as the head of the D.C. National Guard. It was his order that scrambled jets over Washington, D.C., Sept. 11, 2001.
"He was as fine a public servant, as dedicated to the United States of America as anyone I have ever met," Fenty said.
Also on the train was 40-year-old Ana Fernandez, killed while on her way to a nighttime cleaning job. She left behind six children.
Passenger Dennis Hawkins, a 64-year-old retired teacher, died while on his way to teach a Bible class.
And Lavonda King, just 23 years old, was killed as she took the train to pick up her two sons from daycare. Her mother said King had dreamed of a better life for her boys and had recently signed the paperwork to open up a beauty salon.
McMillan, one of the earliest faces of the train accident, was also a mother. She was killed while operating the train that rear-ended the other train.
The son she raised by herself had started college in the fall. Her family said she took pride in her work on the train and ironed her uniform nightly.
"She loved the train. She would talk about what she did at work, or how this works," said her brother, Vernand McMillan.
McMillan recently graduated from bus driver to train operator. Her favorite part of the job? Her relationships with the passengers.
No matter what caused the accident, passengers traveling in the approaching train were in an older car that did not protect them as well as it should have.
Despite the two NTSB warnings, transit officials had refused an upgrade because it would be expensive and complicated.
In 1996, a Metro train of the same series failed to stop and crashed into an unoccupied train in what the NTSB called "catastrophic failure." After the crash the NTSB recommended a comprehensive evaluation of the cars. In 2002, D.C. Metro declined to make any changes. A similar crash took place in 2004, and the NTSB reiterated its warnings.
"In 2006 [the NTSB] asked them to look at old cars," Hersman told "GMA." "They did not retrofit the cars to the standard the safety board was looking for."
Hersman emphasized that the NTSB's role was to make recommendations, and that it was up to local and federal authorities to decide whether to act based on those recommendations.