[UncleHambone]

so if the banked curve is 50 the relatively straight speed could be much faster requiring a slow down at the curve which i don’t think that is how the trains are run there. I think they don’t go over 50 on that stretch.

I read on a train enthusiast site that has many members familiar with Amtrak in general and the area specifically that the limit was in fact 50 mph from Philly Station to the interconnect where the train derailed.

They also stated that the reason there was Positive Train Control on the south/westbound trains but not north/east was that it was considered inconceivable that anyone would get a train going that fast out of the station to reach derailment speed, while trains coming south are dropping from 125 mph limits to the restricted speed at the curve.

[UncleHambone]

Some are also referring to discussion of the “projectile” as the “magic rock theory”.

[kvanbrunt2]

well the distance would allow about 100 mph. It’s about 4 miles on the straight away. and given they are moving about 20-30 maybe around the zoo. according to the youtube test of the very engine it takes about 1 minute to go from 20 mph to 90mph. but the 50 mph on that stretch until you get to 95 is how i recall the trains i was on, actually operate.
https://www.youtube.com/watch?v=vJMhKgEnnNc