OAKLAND — Delays in testing the first 10-car train in BART’s new fleet have already pushed back its rollout by several months, and now officials have nearly halved the number of new train cars expected to hit the tracks this year.

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Did coronavirus just wipe out San Jose’s Google Village? Roadshow BART staff, its governing board and its riders have all been counting on the new train cars to ease crush-load commutes during peak hours, soften the screeching noise of train wheels grating against the rails and improve the passenger experience. The $2.6 billion project will replace all 669 of the agency’s current train cars with 775 new ones. And, if BART can find enough funding, it will add 306 more, bringing the total to 1,081, which works out to a 49 percent increase in capacity systemwide, according to the agency.

Initially, BART officials said they planned to have 60 cars in the new fleet carrying passengers by the end of this year and 230 in service by the end of 2018. That number has since been revised to 35 this year and 166 by the end of 2018, said Jim Allison, a BART spokesman.

BART Director Joel Keller called the revised rollout “disappointing.” The agency’s governing board recently agreed to rip out a row of seats on roughly half of its train cars to add extra standing room and squeeze in more people. Keller said the agency was hoping that would be a temporary measure to add capacity before the new train cars arrive.

“From a customer perspective, this is very regrettable,” he said, “but this is a complicated new train. There is relief on the way; it just won’t be as much relief as we had hoped for.”

Bombardier, the company manufacturing the new fleet, has already begun assembling roughly a dozen new cars, said John Garnham, BART’s program manager for the new fleet. The first of those are not expected to arrive until late July or early August and will require at least a month of testing before it can begin carrying passengers, Garnham said .

If any additional problems arise during testing that require design changes, Bombardier would be responsible for retrofitting them at no cost to BART, he said. At this point, the bulk of the problems are related to software and won’t require major changes to the body of the car itself, he said.

The agency plans to run a test car on BART tracks — without any passengers — during normal hours beginning at the end of this month or in early April. Allison shied away from providing a time estimate for how long the train will operate empty before engineers at BART are satisfied and the state’s Public Utilities Commission gives the agency the OK to carry people.

“Not until they are ready is the short answer,” Allison said. “Not until we know they are safe and reliable.”

Even after the test train starts carting passengers, it will go through at least four more months of performance monitoring, Garnham said. By that time, the agency will be looking only for issues related to the cars’ long-term reliability, he said.

It’s not unusual for problems to arise during the testing process, especially for a piece of machinery more closely resembling an aircraft than an automobile, Garnham said. Each car has some 30 microprocessors, 180 distinct software packages and 93,000 feet of wiring and cabling that must be painstakingly cut out and rethreaded whenever there is a new hardware change, he said.

Testing got off to a rocky start last April when BART’s first test car slowly derailed from the test tracks in Hayward and landed in a sand berm. The $2.2 million train car was not damaged when a wire shorted and cut power to the car’s brakes, but the incident did highlight an issue identified early on with a critical power supply system in the new fleet. That system, called the auxiliary power supply system, provides electricity inside the car for everything from the lights to the doors and communications systems, and a pump that replenishes brake fluid on the car’s secondary braking system.

Engineers have stabilized issues with that system, Garnham said, but the agency has also had problems with the automatic train control system that was failing to stop at the black markers on the platforms where the doors open and close. That system is critical, he said, because it controls all the safety functions within the car, including the brakes and propulsion.

“There’s a lot of software in there,” Garnham said of the automatic train control system. “It’s just time-consuming, because you have to make sure it’s vitally protected. There’s a lot of people’s lives counting on it, and we have to make sure it’s right.”

The agency has completed 275 tests of components within the cars, in addition to the 40 tests completed while the cars were stationary and the 76 tests while the cars were moving on the main tracks. Garnham said he’s confident Bombardier can begin manufacturing the trains while engineers work out the remaining software bugs.

“The car structures are pretty sound. We’ve done the car clearances, so it’s not like we have to shave anything off a sidewall or anything like that,” Garnham said. “It’s basically been the software that we’ve found (issues), and that’s not hard to change out.”

A recent NBC report also claimed the new cars are overweight and could wear down some elevated track structures in BART’s system. BART officials said staff directed its on-call engineering firm to inspect 30 aerial structures beginning this week or next as part of BART’s periodic inspections of its track infrastructure.

“Based upon our regular inspections of our structures and our continual verification of the calculations, we do not have concerns about any increased weight of the new cars causing any of our aerial structures to collapse,” Allison said.