By Rebecca Elliott 

Two U.S. senators have expressed concern about what they said may be an emerging pattern of safety concerns involving Tesla Inc. vehicles in the wake of a fatal crash in Texas.

In a letter Thursday to America's top automotive-safety regulator, Sen. Richard Blumenthal of Connecticut and Sen. Ed Markey of Massachusetts urged the agency to develop recommendations for improving advanced driver-assistance systems such as Tesla's Autopilot.

The National Highway Traffic Safety Administration has opened a probe into the weekend crash, one of more than two dozen investigations it has launched into Tesla-involved crashes. The agency has said that most of those investigations are related to the vehicles' advanced driver-assistance features.

"We fear safety concerns involving these vehicles are becoming a pattern, which is incredibly worrisome and deserves your undivided attention," the Democratic senators wrote about Tesla in the letter, which was viewed by The Wall Street Journal.

A Saturday crash involving a Tesla Model S has increased scrutiny of the car maker's advanced driver-assistance system, known as Autopilot, because the local constable has said that he believed no one was in the driver's seat at the time of the incident. One of the two men who died in the crash in a suburban neighborhood north of Houston was found in the front passenger's seat, the other in the back seat, local officials have said.

Tesla Chief Executive Elon Musk said Monday that data recovered so far showed Autopilot wasn't enabled. He didn't specify whether that meant at the time of the crash or at any time during the preceding drive. Tesla didn't respond to requests seeking clarification.

NHTSA had no immediate comment.

Rep. Kevin Brady (R., Texas), who represents the area where the crash took place, on Thursday joined the growing chorus of lawmakers seeking more information.

"I support progress that's being made and the development of new technologies for autonomous and semi-autonomous vehicles, but we need answers to what happened," Mr. Brady, the top Republican member on the House Ways and Means Committee, said on a call with reporters. "I and those families deserve answers to ensure that as companies are developing -- specifically Tesla -- these new technologies, there is not a loss of innocent lives as we do that."

Another federal organization, the National Transportation Safety Board, also has launched an investigation into the incident. The board, which has the power to issue safety recommendations, has said its review will focus on both the operation of the vehicle and the postcrash fire, which local officials have said took hours to extinguish. Batteries used in electric vehicles can reignite after initial flames are put out, as this one did, said Palmer Buck, chief of The Woodlands Fire Department, which responded to the incident.

The senators' letter speaks to a tension that regulators face with driver-assistance features such as collision warning or adaptive cruise control. The technology can help make driving safer, but also introduces new risks.

"While automated driving and driver assistance systems -- like the Autopilot feature on Tesla cars -- can help prevent injurious and fatal accidents, they must be implemented strategically and safely," the lawmakers, who both sit on the Senate Committee on Commerce, Science and Transportation, wrote.

Tesla says that driving with Autopilot enabled is safer than driving without it. Hours before the Saturday crash, Mr. Musk tweeted: "Tesla with Autopilot engaged now approaching 10 times lower chance of accident than average vehicle."

NHTSA doesn't have any rules in place specifying how companies must go about ensuring that drivers are paying attention while driver-assistance systems are engaged. The NTSB has said that lack of regulation puts people at risk.

The Texas crash has left questions about whether or how the vehicle could have been operating without anyone in the driver's seat.

Tesla has said that drivers using Autopilot must remain attentive with their hands on the wheel and that it has safety features, including aural and visual alerts, to remind them to stay engaged.

Consumer Reports on Thursday said it had done tests this week in which it was able to get a different Tesla model's Autopilot to operate without anyone in the driver's seat. The vehicle, which uses steering-wheel inputs to assess driver attention, didn't send any warnings about an empty driver's seat, Consumer Reports said. The organization attached a weight to a Model Y's steering wheel to simulate a hand during the testing.

"I was really shocked how easy it was to do it," said Jake Fisher, the group's senior director of auto testing, one of the people involved in the test-track experiment. "When you have an automation system like that which explicitly needs a driver to be ready to take over at any time, you have to make sure that someone is actually engaged."

Tesla didn't respond to a request for comment on the Consumer Reports finding.

Write to Rebecca Elliott at rebecca.elliott@wsj.com

 

(END) Dow Jones Newswires

April 22, 2021 14:55 ET (18:55 GMT)

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