Car operating in autonomous mode struck a semi truck trailer.

The National Highway Traffic Safety Administration is opening an investigation into a fatal accident with a 2015 Tesla Model S operating in Autopilot autonomous mode. NHTSA’s study is a “preliminary” investigation that intends primarily to determine “the design and performance of any automated driving systems in use at the time of the crash.”

The crash occurred when a 2015 Tesla Model S was driving on a divided highway, and a semi truck drove into the car’s path. Tesla says that neither the Model S’s driver nor its Autopilot system detected the white trailer against “a brightly lit sky.” The Model S ran underneath the trailer and the car’s driver was killed. Tesla said that if the car had hit the rear of the trailer, “its advanced crash safety system would likely have prevented serious injury as it has in numerous other similar incidents.”

Tesla notes that this is the first confirmed death from any car running with its Autopilot self-driving systems enabled, after a cumulative 130 million miles of Autopilot use worldwide. In the U.S. as a whole, Tesla claims, there’s an average of one fatal accident every 94 million miles driven.

Nonetheless, Tesla stressed today that drivers should still pay attention when using the Autopilot feature. “Autopilot is getting better all the time, but it is not perfect and still requires the driver to remain alert,” the company said. “Additionally, every time that Autopilot is engaged, the car reminds the driver to ‘Always keep your hands on the wheel. Be prepared to take over at any time.’”

The sad news of this fatal crash comes after several other drivers have blamed non-fatal crashes on Tesla Autopilot, and after one driver was spotted sleeping while his Tesla drove in Autopilot mode.

You can read Tesla's full statement in the press release section below.

Source: Tesla

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