Mr. Laser Beam wrote:
^ I take it it's not realistic to ever expect BART itself to reach all the way out to the airport?
Pretty much not, yeah.
Extending BART itself out to the airport would probably cost more than this connector thing. As an alternative
to the connector, it's doubtful that it would have gained much traction, but it was theoretically possible.
However, now that they are going ahead with the OAC, there's no chance of BART itself ever being extended. Reason being that the infrastructure that is being built for the OAC is incompatible with BART's infrastructure - it's a cable-pulled short train (basically heavy trams that can be connected together) and will use standard gauge track as far as I know. So, the non-standard gauge, third-rail powered multiple units that make up BART's mainline service wouldn't be able to use the finished trackway. Now that the OAC is going ahead, connecting BART itself to the airport would require essentially building an elevated trackway AGAIN for BART trains, after having already built an elevated trackway for OAC vehicles. Not gonna happen.
That said, I'm not sure how much of an advantage it would have been vs. the OAC anyway. The only real upside is it would mean you don't have to switch vehicles. They'd still have massive costs to recoup, so the fare to get to the airport would probably be pretty high (I could see a surcharge like the one that applies for any trips to SFO, which is about $4 now IIRC. It used to only be about a dollar, but in the face of budget shortfalls and ridership to/from SFO being below expectations, they hiked it). Plus, again like with SFO, if mainline BART trains go straight into the airport, you end up with a kind of Bermuda Triangle of routes, where you have service that travels through the existing Coliseum Station (going north-south), and then this side track that juts off west and goes over to the airport; do north-south service trains simply go to the airport and then continue on their way, adding several minutes to the existing trip? Or does one line go to the airport while others don't, potentially undermining frequency of service? Or does it depend on line and time of day and whatnot, which just creates confusion for riders?
The physical configuration creates a problem in this case, and its effects have already been seen with the SFO line, which has the same problem - BART's approach to which lines go to SFO vs. which ones don't and how it all works has changed like six times since that station was built.