It’s the ultimate BART delay: How long until the transit agency’s roughly $2.6 billion new “fleet of the future” is delivered in full?

The answer, evidently, is a little longer, as the full rollout of 775 new vehicles is once again delayed by several additional months and isn’t expected until 2023.

According to the San Francisco Chronicle’s Rachel Swan, the biggest part of the holdup is that the new vehicles are running into problems more often than anticipated.

Lead cars are supposed to run 6,000 miles between major delays, but at present only manage one-sixth of that; middle cars are supposed to go 12,000 miles between problems, but in tests have averaged less than 10,000. Every one of these fixes puts time on the clock.

Once upon a time, the agency hoped to have its full 775 vehicle order ready by mid 2022. Then the date shifted to fall 2022.

Now spring of 2023 is the latest ambition.

Delay has been the name of the game all along: The original target date for the first new coaches to begin passenger service was the end of 2016; they didn’t appear until January of 2018.

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By halfway through 2018, BART once planned to have 150 new cars in operation. Instead it had only 20.

In April, BART Senior Web Producer Melissa Jordan wrote on the BART blog that, by the end of the month, “BART expects to hit a milestone with 80 new train cars, enabling one 10-car Fleet of the Future train to be running on each of BART’s five lines, with the rest still undergoing testing and being used for training.”

Previously, BART had hoped to hit said milestone by the end of 2018.

As of now, BART has 84 cars in its possession, but only 75 are certified for operation. The agency still hopes to receive 260 by year’s end.

Because the cars have not been tested when they arrive, new vehicles frequently need adjustments—sometimes hundreds of them, according to BART’s communications team—which, in turn, requires more testing and more repairs when more problems arise.

The 775 new cars are meant to replace BART’s current aging stock of 669 vehicles. The agency hopes to one day up the full fleet to 1,200 of the new Canadian-built coaches—but for now commuters must rely on the originals for a bit longer.

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