BART's Oakland Airport Connector has reached a new milestone this week: A train completed its first fully automated loop around the system from the Coliseum station to airport terminals.
The Oakland Airport Connector runs on a cable system — pretty similar to the San Francisco cable cars, but without drivers. The system has four cable loops and one train per cable. The trains automatically switch cables four times: once at each end, and halfway between the two stops.
That halfway point is called the wheelhouse, and inside are four giant wheels with spinning cables. The noise from those spinning cables is almost deafening.
But outside, the trains are almost silent. You can barely hear cars as they approach.
"There's no motors. The only hum you hear is from the air conditioner. Otherwise, it's going to be dead silent." said project manager Tom Dunscombe.