[flickr]photo:2720457290[/flickr]
1977 derailment at Wabash and Lake – photo by Mark Llanuza
[This piece also ran in Time Out Chicago magazine.]
Q: Since I’ve switched from the straight-shot Red Line to the winding Brown Line, where you often feel like you’re about to ride right off the rails (and right into a nearby condo building), I’ve been wondering: At what speed would El trains hitting sharp curves come off the tracks?
A: A CTA train’s extremely low center of gravity and speed limits allow it to safely navigate the El’s many curves, according to spokeswoman Catherine Hosinski. As a train goes around a bend, like the tight S-curve on the Brown and Purple Lines just north of the Merchandise Mart, the car may seem to sway at an impossible angle, but most of the weight is still directed straight down, Hosinski says. This overcomes centrifugal force and keeps the wheels on the rails. “Also, a train’s speed through each curve is limited by the automated train control system,” she says. “This system enforces a maximum train speed that’s much lower than the speed that could cause a train to leave the rails.”
Continue reading What keeps an El car from falling off the tracks on tight curves?