UNIVERSITY CITY (WPVI) -- Investigators believe the Amtrak train that derailed in Philadelphia was hurtling through a 50 mile per hour zone at more than 100 miles per hour.
But according to a local train expert, speed may not be the only factor at play.
The NTSB will continue to look at a number of different factors - anything and everything that could have contributed to this catastrophic event.
Dr. Joseph Martin, Civil Engineering Professor from Drexel University, is quite familiar with the particular stretch of rail where Tuesday's Amtrak crash occurred.
Martin says investigators will do basically an autopsy of the train - carefully analyzing each piece of metal.
They do now have the locomotive's event recorder, which will confirm the train's speed, throttle position, and brake operations.
"Notice that one of the cars is completely cut in half. Something made the trains roll over. This is beyond unusual," said Martin.
Amtrak 189 crashed just a mile from the site of the nation's deadliest rail crash in 1943, but Martin doesn't believe the track's bend could have been a major factor.
"The fact is a million trains have passed between events so it wasn't geometry. It's a very gentle curve," said Martin.
According to the Federal Railway Administration, Amtrak inspected that stretch of track just hours before 188 derailed and found no defects.
"I don't see the track being the issue because it's new and it was built for Amtrak," said Martin.
The locomotive itself is relatively new, too. Its maker reportedly having delivered it to Amtrak just last year.
"Was there something that caused that momentum? Something that dropped on the tracks or whatever. That's what they don't know," said Martin.
And certainly that is what investigators are trying to figure out.
Despite this initial finding about speed, Martin says it could take months to conclude this investigation which certainly will be one of the most closely watched rail investigations we have ever seen.
Drexel rail expert discusses Amtrak train crash
More TOP STORIES News