The Tesla driver killed in a crash while in autopilot mode happened to be a huge proponent of autonomous driving.
Joshua Brown of Canton Ohio was driving with autopilot on a Florida road in May. As a tractor-trailer turned in front of Brown, his Tesla plowed ahead -- its roof striking the underside of the trailer and passing underneath it. The Tesla (TSLA) continued to drive, striking two separate fences and a utility pole before finally stopping. A portable DVD player was found in the vehicle, and the Florida Highway Patrol is investigating whether it was on during the crash, according to a spokeswoman.
On Thursday, U.S. regulators said they're investigating Tesla's autopilot system.
The autonomous mode is meant to handle some, but not all, driving situations. The software isn't perfect, and Tesla advises human drivers to keep their hands on the wheel at all times, and to stay alert.
Related: Tesla's autopilot probed by government after crash kills driver
Brown has posted 24 YouTube videos demonstrating the power of the technology since it was released in November of 2015.
"It'll say hold the wheel if it's unsure of its situation and it wants you to be prepared," Brown said in one video posted the day after Tesla launched autopilot. "If you don't take control, the car starts to brake and stuff. I've already done some testing with that, and yes it definitely starts to abruptly slow down."