What makes a '5' train a '5' train? Is it the route it travels, or the '5' displayed on its front car? I'd go with the former.
The '5,' after all, doesn't apply to the actual, physical train. (I'm guessing each car has its own serial number, though I confess I've never mustered the nerve to lie down on the track and check.)
The '5' applies to a path: snaking through Brooklyn, piercing Manhattan at its southern tip, then climbing up the east side before leaning right in the Bronx.
Why, then, does our transit system continue to confuse us (or at least me) by putting '5's where they don't belong? Every so often, a so-called '5' train comes rumbling through the west side of Manhattan on tracks reserved for the '1,' '2' and '3' (R.I.P. '9').
"The '5' train is running on the Seventh Avenue line," a garbled voice announces. I think what they're trying to say is this: The '2' isn't running, so this car will take a different route — the '5' route — in Brooklyn and the Bronx.
But I still say a '5' is not a '5' when it's on the Upper West Side. Why not change the number on that front car's digital screen to reflect the detour to the land of '2'? Then announce that this train is a '2' now, but will suffer an identity crisis and become a '5' at Grand Concourse.
When a '5' train leaves the east side, the '5' should stay behind, too.
-- David Abramowicz