2005 Philadelphia Amtrak derailment

Used as the worked example for the *five whys* technique. **Note:** Tom dates this as recent ("a few years ago") and attributes engineer impairment to drugs — both points may need editor verification. Canonical case in the aggregate is dated 2005; Tom may be referring to the 2015 derailment instead.

I think I talked about this last time. If you want to get to the root cause of a problem, you keep asking why. A few years ago in Philadelphia, an Amtrak train jumped the rails coming into 30th Street Station. Why did the train jump the rails? The first answer: he was doing 50 miles an hour in a 30-mile-an-hour zone. Around the curve, you go too fast, you jump the rails. Why was he going 50? He was on drugs. You can do the same thing with the MBTA cars around here. There's nothing magic about five whys — it could be four, it could be six. If you keep asking why, like a three-year-old asks their mother, and you keep answering, eventually you get to the root cause.