by Tommy Meehan
Ridgefielder wrote:I just figured that's simple physics. A Shoreliner weighs something like 100k lbs. A P32AC-DM weighs 274k lbs. Once the train hits the dirt, of course it's going to take the locomotive longer to skid to a stop than the passenger cars-- it weighs 2.75x as much.This is two different issues. You're talking about braking rates. Other people are speculating the locomotive continued under power pushing the train after the derailment began.
I don't know off hand what the braking distances are for coaches vs. locomotives. I do know that brakes are designed to do things like stop a fully loaded coach (all seats occupied plus standees) in the same distance as an empty coach. They're called self-adjusting brakes. That's so the braking distances remain constant for station stops. So the engineer doesn't have to be looking out the window at stops to see how many people are getting on board in order to know where to begin braking for the next station. Somewhere in here one of the railroaders mentioned that the brakes are set up so the locomotive brakes at pretty much the same rate as the coaches. Brakes are adjustable, they can be set up to give different rates of deceleration.