The National Transportation Safety Board has published its first findings after investigating a fatal highway crash in 2016 involving a Tesla Model S and a tractor trailer.

The crash occurred on last summer after 40-year-old Joshua Brown was driving with Tesla's Autopilot engaged.

The system failed to apply the brakes when a tractor trailer turned left in front of him and left Brown dead on impact.

DON'T MISS: NHTSA to investigate Tesla Model S Autopilot crash that killed driver: UPDATED

Although Autopilot failed in this instance, it turns out there's considerably more to the story.

The NTSB says Brown ignored repeated warnings from Autopilot to retake control of the car.

In Tesla's statement following the fatal crash, it said the incident occurred because "neither Autopilot nor the driver noticed the white side of the ... trailer against a brightly lit sky, so the brake was not applied."

Tesla Enhanced Autopilot

Tesla Enhanced Autopilot

Brown reportedly kept his hands off the wheel for extended periods of time, despite Autopilot's audible warnings to not to do so, according to the 500-page docket from the NTSB.

The truck driver involved in the crash also claimed Brown was watching a movie at the time of impact—an aftermarket DVD player was found among the wreckage.

Following the incident, Tesla updated its Autopilot system to temporarily prevent drivers from using the system if they do not respond to audible warning urging them to take control of the car.

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Tesla also reminded owners Autopilot is still in a "public beta" testing phase.

Drivers should continue to remain alert in order to take control of the car again at all times while Autopilot is engaged.

Tesla has also shied away from calling its Autopilot system an "autonomous car."

Tesla Autopilot sensor system

Tesla Autopilot sensor system

The system is handicapped in rain and snow, and it's best used in dense traffic situations where lane markings are clear and legible.

On a scale of autonomy, used by the National Highway Traffic Safety Association, Autopilot ranks low; on a scale from 0 to 5, with 0 representing no autonomous capability, Autopilot remains a 2.

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So, let us be clear: Autopilot is not a ticket to disengaged driving habits.

Rather, it's a luxury that should be treated with the continued respect of road rules.


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