We know the speed limit on the curve was 50MPH. Do we know what it was just before the curve? I haven’t seen it anywhere...
The posted speed ahead of the curve was 70 MPH. The coal trains that I rode on the open rails during testing would limit speed to 80 MPH. The Timken bearing generator in my equipment package included a 12-pole Hall effect tachometer. I could calculate the angular velocity from the tach pulses. The wheel diameter was 36 inches. 747 RPM.
The point is the engineer was exceeding the posted speed limit on entry into the turn and in the turn where 50 MPH was the posted speed.
i bet close to of not 50 for a good distance from the curve.
It’s fairly straight most of the way from about the zoo to the curve. past the north philly station. Read about how fast the trains can accelerate. amazing.