New BART cars are expected to start carrying passengers in late September following final testing this summer, BART officials said Monday.

Last week, crews began another phase of testing when they started running 10 new cars on the main tracks during business hours and Monday brought members of the media for a ride.

Before the latest phase of testing, crews ran tests on the main tracks between midnight and 4 a.m. and before that on test tracks at the Hayward Maintenance Facility.

Earlier this week crews were set to run the new cars between the Bay Fair and Warm Springs stations.

"We've made significant progress in the past few months," new car project manager John Garnham said.

Crews have 391 tests to perform on items like the brakes, lighting, propulsion and the passenger information system.

The testing has prompted officials with BART and manufacturer Bombardier Transportation to make 3,000 modifications, most of which are software-related.

Train operator Kirk Paulson, who has been operating a train made up of the new cars, said he would give the train an A for operation, up from an F when the modifications began.

"You have to make sure it's right," Garnham said.

He added that he appreciates the patience of passengers awaiting the new cars.

Thirty-five new cars are expected to be in BART's possession by the end of the year. BART has 669 cars now and 775 will make up the new fleet.

BART officials are replacing the cars because they are at the end of their 40-year useful life.

Paulsen said operating the new train is "like driving a Tesla," compared with the old ones, which he described as a Model T.

"It's smoother," Paulsen said. "It's quieter."

BART spokeswoman Alicia Trost attributed the quieter ride to a different wheel interface and the doors, which should seal out the noise better than the doors on the older cars.

Crews are in the process of measuring the noise and the results will be made available to the public.

Paulsen also said the visibility is better in the new cars, especially at night.

Trost said other improvements include a digital passenger information system, a modern public address system so passengers can hear announcements better, and the signs on the outside of the trains, which will make it easier for passengers to know the train's destination.

BART officials hope to have all 775 new cars in service by 2021.

-- Keith Burbank, Bay City News