It's been almost a year since BART launched new trains. So where are they?

A new BART train makes a stop at the Powell Street Station on Wednesday, Oct. 24, 2018, in San Francisco, Calif. After many delays, BART has begun running its new trains on complete routes from the East Bay to stations in San Francisco and Daly City. less A new BART train makes a stop at the Powell Street Station on Wednesday, Oct. 24, 2018, in San Francisco, Calif. After many delays, BART has begun running its new trains on complete routes from the East Bay to ... more Photo: Santiago Mejia / The Chronicle Buy photo Photo: Santiago Mejia / The Chronicle Image 1 of / 34 Caption Close It's been almost a year since BART launched new trains. So where are they? 1 / 34 Back to Gallery

It's called the Fleet of the Future, and aptly so. The shiny new BART cars are a rare sight on the transit system's 121 miles of railway, and the days when we'll all be riding them around the Bay Area are still a ways off.

The fleet was first shown off to the media back in July 2017. It was a bumpy ride, to say the least, but there were noticeable improvements; the trains were quieter, more spacious, and best of all, clean.

When the first train of the new fleet started traveling the Richmond to Warm Springs line (the BART line with the lowest ridership), those lucky enough to score a ride were pretty pleased. That was in Jan. 2018. Ten months later, on Oct. 24, the new model debuted on a transbay route, from Daly City to Warm Springs.

That's two trains in 10 months.

So, what's taking so long? There are a couple key factors slowing the fleet's rollout to a glacial pace.

First off, BART is inconveniently unique. The tracks are wider than standard gauge, which is the width used on the overwhelming majority of transit systems around the world.

"This means that the new rail cars can't be tested at the factory – they need to be shipped to BART property and tested on tracks here," said BART spokesperson Jim Allison. The new cars had to be brought from where they were manufactured in upstate New York all the way to Hayward, where they were tested and modified.

When they arrived in the Bay Area, Allison says "the first 10 pilot cars were far from a finished product."

"Once we got the pilot rail cars on our test track, we began putting them through the paces and found numerous changes we wanted to make before the production line ramped up," said Allison. "Each car has 30 microprocessors and 180 distinct software packages. That's lot of components to test and modify."

BART eventually identified 2,900 modifications that needed to be made to the pilot cars.

The technological upgrade is so significant that training operators is also taking some time.

"Imagine comparing a 2018 automobile to a 1972 auto. Both have engines and four wheels but think of all the electronic and computer components of a modern automobile compared to a '72 Pinto," Allison said.

BART approved 30 new cars to carry passengers, but 20 cars (the equivalent of two 10-car trains) are being used to train operators. Allison says half of BART train operators have completed the training so far.

All this means: It could be a while until you're riding one of the clean, new trains to and from work

BART hopes to have five 10-car trains in service by the end of the year, one on each line. Next year, you should be seeing more of them — 260 new cars will be in rotation by the end of 2019, says BART spokesperson Alicia Trost. But the entire fleet of 775 cars won't be in action until spring 2022.

"The time we've spent doing this is well worth it if you consider we need these cars to carry passengers for the next half century," says Allison.

Read Alix Martichoux's latest stories and send her news tips at amartichoux@sfchronicle.com.

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