Subway Cars With No End in Sight

The most notable feature of the new model is its articulated design. Rather than having separate cars with doors between them, the new model has segments that move in unison with slinky, open joints that let riders move along the train’s length, even while it’s in motion.

The Metropolitan Transportation Authority, the state agency that runs the subway, said that these were the first trains with so-called open gangways to be deployed in the United States in decades. From 1925 to 1965, New York’s subway system included articulated trains made up of three segments.

The new trains have built-in security cameras, wider exit doors and digital screens in every car. They also have more space for riders with disabilities than older models.

The M.T.A. has added only two trains with the new open-gangway model. One train features a soft shell between cars; the other has a hard shell. The authority said that it was only experimenting, and that it had not committed to a wider deployment of the new model.