Then why does it work just fine with one conductor in most other metro systems?
> And in some curved stations, the driver can't even see to the rear end of the train.
Mirrors and CCTV are a thing. At the Berlin metro, the platform has a big mirror or a CCTV screen array next to where the train cockpit stops. Other metros' stations have wireless CCTV systems that show up inside the cockpit while the train is stopped.
Note that NYC trains have just one conductor, AFAIK. The second person is the driver.
For dragging, it's not just where the train stops. You have to be able to see the entire side of the train as it leaves the station (e.g., for 100 meters, at least).
Video might be possible, but it'd need to be attached to the train, because that's where the dragging happens. Realistically, though, NY doesn't have the money for this conversion. And more importantly, the driver needs to attend forward, not be carefully watching the dragging video.
> Note that NYC trains have just one conductor, AFAIK. The second person is the driver.
Sorry, that was lost in translation. By "conductor", I meant "driver". All the metro trains that I know have only one personnel on board, the driver.
Also, what do you mean by "dragging"? People or clothes getting stuck in a door? It seems to be very important, but I've never heard of this being a large problem in practice.
Dragging as in clothes, backpack, or an arm caught in a door, or someone falling in the crevice between the train and platform, or trying to "surf" the train, etc.
Not sure, but I think incidents happen with some regularity in NY. If you haven't seen it, it might be hard to visualize just how out-of-date and decrepit some of this infrastructure is. I never saw anyone injured, but I did see a couple of close calls that still make me shudder.
> And in some curved stations, the driver can't even see to the rear end of the train.
Mirrors and CCTV are a thing. At the Berlin metro, the platform has a big mirror or a CCTV screen array next to where the train cockpit stops. Other metros' stations have wireless CCTV systems that show up inside the cockpit while the train is stopped.