Manhattan Bridge

I've noticed that the lines that run over the Manhattan Bridge (particularly the Broadway side--Q/N) seem to run very slowly over the bridge. My Q train this morning maxed out at 21 mph, and there were only green signals ahead. I'd say that these speeds are typical, though I don't usually look at the T/O's speedometer. The trains run much faster on the next segment, between Canal and 14th Streets, though they also seem to run slowly between 7th Ave and DeKalb in Brooklyn.

So why are these lines slow? Is it related to the ongoing bridge renovations? Grades? Are there any plans to increase the speed?

Bridge design limitations.
Suspension bridge deflects greatly when a train enters the span. Unlike Williamsburgh, where the tracks run along the center of the bridge, the tracks on the Manhattan Bridge give the bridge deck a pretty good "twist" and to keep the DOT happy, the trains enter and exit slowly.

Make for a more enjoyable view <grin>
John

yep I noticed this yesterday too