Tesla CEO Elon Musk speaks before unveiling the Model Y at the company's design studio in Hawthorne, Calif., on March 14. (Jae C. Hong/AP)

Tesla’s Autopilot system was active in a Model 3 that collided with a tractor-trailer during a fatal crash in March, the National Transportation Safety Board said Thursday.

The crash in Delray Beach, Fla. that killed the Tesla driver is at least the third deadly collision in the United States involving the company’s advanced driver-assistance features, adding to questions about the safety of the technology and how drivers rely on it.

“Preliminary data from the vehicle show that the Tesla’s Autopilot system—an advanced driver assistance system (ADAS) that provides both longitudinal and lateral control over vehicle motion—was active at the time of the crash,” NTSB said in a preliminary report. The Autopilot system was turned on about 10 seconds before the crash, the report said, and the vehicle did not detect the driver’s hands on the steering wheel during the final seconds before the collision.

Tesla’s Autopilot is a driver-assistance system designed to keep vehicles at speed, maintain a safe distance from traffic and follow road markings; it enables vehicles to steer, accelerate and brake. But Tesla says that its autopilot features require “active driver supervision” with their hands on the wheel and that the system is not autonomous.

The posted speed limit on the highway where the crash took place was 55 mph, the NTSB said. But vehicle data showed the Tesla was traveling at about 68 mph when it hit the semitrailer. The report found that neither the driver nor the autopilot system made evasive maneuvers to avoid the crash.

In a statement, Tesla said the driver “immediately removed his hands from the wheel,” after engaging the Autopilot. “We are deeply saddened by this accident and our thoughts are with everyone affected by this tragedy,” the company said. The driver was Jeremy Banner, 50.

“Tesla drivers have logged more than one billion miles with Autopilot engaged, and our data shows that, when used properly by an attentive driver who is prepared to take control at all times, drivers supported by Autopilot are safer than those operating without assistance.”

The latest crash report comes as Tesla continues to develop its driver-assistance system and as chief executive Elon Musk sets ambitious goals for the company’s self-driving capabilities. During investor presentations at the company’s “Autonomy Day” last month, Musk said a network of autonomous Tesla taxis will be able to shuttle passengers by the end of next year. Musk also envisions the production of Tesla vehicles without steering wheels within the next two years.

But some critics say that autopilot technology can give drivers a false sense of security, and that boosterism surrounding autonomous vehicles is setting the industry up for failure.

One family whose relative was killed in a Tesla crash in 2018 is suing to hold the company responsible. The loved ones of Walter Huang, a 38-year-old Apple engineer, who died driving his Tesla Model X SUV in Mountain View, Calif., filed a lawsuit against Tesla alleging wrongful death and negligence stemming from failures and false promises tied to its driver-assistance system.

Another Tesla driver who had Autopilot engaged died in a crash in May 2016, when his Model S slammed into a semitrailer in Williston, Fla.