The current issue of New York magazine features a piece by me on the current frailties facing the city’s subway system — which is over 100 years old now and still has many of its original parts! Quite apart from the question of the crisis, the story was a blast to write, merely because the system’s famous complex engineering is really interesting. As I called it, New York’s subway is “the world’s most remarkable Rube Goldberg device — with cutting-edge fiber-optic switches sitting alongside pre-World War II Bakelite phones, custom-engineered radio cable running along areas festooned with dripping stalagmites, and passengers streaming obliviously by, barely glancing up from their BlackBerrys.”

As any engineer knows, with that many moving parts, whatever you’re not actively fixing is in the process of breaking. And for ten years now, the subway has been mercilessly screwed for maintenance-and-upgrading cash by New Yorker governor George Pataki. So my piece opens with a hypothetical disaster:

Picture this: Sometime in the near future, you get on a subway train heading into Brooklyn, and zoom into the tunnel. Unbeknownst to you, though, something bad is happening on the other side of the river. A track fire is smoldering. Throughout the subway, there is fine-grained metal dust that comes from the constant grinding of wheels on rails. It’s combustible stuff, and tonight, as the train ahead of you leaves the station, the 600-volt current from the third rail arcs and ignites some of the dust, like a Fourth of July sparkler. The sparks torch a mess of paper wedged on the tracks, left behind because budget cuts have resulted in fewer cleanups. Normally these fires are a mere nuisance—but this one really gets going, and soon the tunnel ahead of you fills with acrid smoke. The tunnel’s nearest ventilation fan hasn’t been fully repaired, so the smoke doesn’t clear. The motorman tries to contact his command center, but his radio has hit one of the system’s “dead spots,” so he gets no signal. Chaos ensues: The car fills with smoke, nobody has any clue what’s going on, and a bunch of passengers start kicking out windows in a bid to escape.

Hypothetical, but, as I found out, not far-fetched. If you want to read the whole story, it’s online here, or if you’re local, buy a copy on the newsstands now!