PALO ALTO, California — In a Wednesday blog post, Tesla Motors offered a deeper look into the May 7 fatality of a Tesla Model S driver using the Autopilot semi-autonomous system, saying a collision on Autopilot "was a statistical inevitability."
The posting said: "Customers using Autopilot are statistically safer than those not using it at all."
But it noted "given its nature as a driver-assistance system, a collision on Autopilot was a statistical inevitability, though by this point, not one that would alter the conclusion already borne out over millions of miles that the system provided a net safety benefit to society."
The latest Tesla blog post, headlined "Misfortune," takes aim at Fortune and mounts a defense for the Autopilot system and its benefits. Fortune alleged that Tesla withheld information from shareholders regarding the fatal crash.
"Fortune's article is fundamentally incorrect," Tesla said.
The latest blog post provides a crucial timeline about the crash and its aftermath.
Tesla said it told the National Highway Traffic Safety Administration about the crash on May 16. On May 18, a Tesla investigator went to Florida to inspect the car and the crash site, along with pulling complete vehicle logs from the car.
"It was not until the last week of May that Tesla was able to finish its review of those logs and complete its investigation," the company said.
It added: "To be clear, this accident was the result of a semi-tractor trailer crossing both lanes of a divided highway in front of an oncoming car. Whether driven under manual or assisted model, this presented a challenging and unexpected emergency braking scenario for the driver to respond to. In the moments leading up to the collision, there is no evidence to suggest that Autopilot was not operating as designed and as described to users: specifically, as a driver-assistance system that maintains a vehicle's position in lane and adjusts the vehicle's speed to match surrounding traffic."
On June 28, NHTSA opened an investigation into an estimated 25,000 2015 Model S sedans to examine the design and performance of any automated driving systems in use at the time of the crash.
NHTSA also is looking into a July 1 crash in Pennsylvania of a 2016 Tesla Model X SUV. NHTSA will determine whether the vehicle was in Autopilot mode at the time of the crash.
Edmunds says: Even though Tesla has drawn conclusions about the fatal crash, federal safety regulators still need to finish their work and make their determinations about what happened.