and then they have an idea that the engineer jammed on the brakes which tells you he knew he was going to fast and tried to avert disaster. >> with what we know, it is hard not to think that human error is playing some role here. now i suppose it's possible there is some mechanical set of events that would cause a train to sort of speed out of control. >> yeah. >> but from what we know, certainly things seem to be pointing in that direction. the other thing i would say before you get to that bend, there is a long straightaway. i mean, you're four or five -- you're about five miles from 30th street station. but you've been now going two miles straight away. an electric locomotive like that, not diesel, right, those things accelerate very quickly. they don't have combustion engines. they accelerate in a almost linear fashion. they can get up very fast very quickly. >> this is one part of the country where people take trains still. everybody loves them. you don't have to think. you don't have to pray. it's usually a safe ride. get on the train, you go to sleep, do some homework, read the paper.