Didn't really need to going all that fast, seems like the direction was more important than speed.
I think the car ran through the 40 year old railings, taking out a vertical post. The car then rolled over a 8" wall, (aided to climb up by the leaning post) about a yard, and toppled down into the subway. fortunately the noise of the fence coming down alerted a mother who grabbed her children out of the way. The car still has it's windows intact, and may well be drivable.
Could've been a lot worse!