What caused fatal Tesla crash?

An investigation by the National Transportation Safety Board (NTSB) has determined that "operational limitations" of Tesla's Autopilot system played a "major role" in a fatal crash last May, but that the driver was also at fault for not paying adequate attention to the road. Tesla owner Joshua Brown was using the semi-autonomous system on a Florida highway when both he and the car failed to notice a tractor-trailer turning left across the road. At the time, Autopilot was capable of steering the car within its lane and autonomously braking for vehicles in the road ahead. Following the incident, Tesla said that the vehicles sensors were unable to identify the white truck against the bright sky behind it. According to Reuters, the NTSB found that the system worked as designed, but should've done more to ensure driver attentiveness and restrict its use to highways and limited-access roads.