Police said no one was in the driver's seat at the time of the crash.
Lars Moravy, Tesla's vice president of vehicle engineering, said on the company's earnings call Monday that Tesla's adaptive cruise control was engaged and accelerated to 30 mph before the car crashed.
Autopilot is a suite of driver assistance features, including traffic-aware cruise control and Autosteer, according to Tesla's website
. Traffic-aware cruise control matches the speed of the car to surrounding traffic, while Autosteer assists in steering in clearly marked lanes according to Tesla's website.
The North American owner's manuals for the Model 3
, Model S
and Model X
, all describe traffic-aware cruise control as an Autopilot feature.
Tesla's revelation may be at odds with the initial description of the crash from its CEO Elon Musk, who said
two days after the crash that "data logs recovered so far show Autopilot was not enabled."
It's unclear, however, whether Musk was defining Autopilot in a way that was most beneficial to his company by referring to the entire suite, rather than the individual features that make up the suite.
Model S drivers can activate traffic-aware cruise control at the currently detected speed limit by pulling the Autopilot stalk on the steering wheel toward them, according to the car's North American owner's manual
. Pulling the stalk toward them a second time, in quick succession, will activate Autosteer, if the system is available.
The process is similar on other Teslas. Drivers engage traffic-aware cruise control on the Model 3 by moving the stalk down and releasing, according to the car's North American owner's manual. Moving it down twice quickly turns on Autosteer.
Autopilot's current features require active driver supervision and do not make the vehicle autonomous, Tesla says on its website
. Tesla warns drivers that they must be attentive and prepared to take over.
The Tesla that crashed in Texas did not have Autosteer active, Moravy said on Monday's earning call.
Bryan Reimer, the associate director of the New England University Transportation Center at MIT, who studies driver assistance systems like Autopilot, said one of the plausible explanations for the crash is that the driver was confused and thought they had activated Autosteer, when only traffic-aware cruise control had been turned on.
"The general understanding of Autopilot is that it's one feature, but in reality it is two things bolted together," said Reimer, referring to traffic-aware cruise control and Autosteer.
Tesla did not respond to a request for comment and generally does not engage with the professional news media.
Musk fielded a question on the earnings call Monday that claimed the mainstream media has "massive and deceptive clickbait headline campaigns on safety of Autopilot."
"There was an article regarding a tragedy where there was a high-speed accident in a Tesla. But and there was really just extremely deceptive media practices where it was claimed to be Autopilot when this is completely false," Musk responded.
Musk did not make clear if he was referring to the Texas crash, or another crash. He referenced a "high-speed" crash, but Moravy later said the Model S in Texas accelerated to 30mph.
Moravy also said it was likely that someone was in the driver's seat at the time of the crash because Tesla found that the steering wheel was "deformed." He did not explain what he meant by "deformed," or if that could have occurred in the crash even if a person wasn't sitting in the drivers' seat.
Tesla first released Autopilot in October 2015
. It described Autopilot at the time as allowing Teslas to steer within a lane, change lanes with the tap of a turn signal and manage speed with traffic-aware cruise control. Autopilot has been popular with Tesla consumers, and it has differentiated Tesla from other vehicles for sale.
It also has been criticized, including by the National Transportation Safety Board, following two previous fatal crashes. In 2017, the NTSB
called on Tesla to develop better ways to make sure that drivers were paying attention to the road.
The NTSB and the National Highway and Traffic Safety Administration have both said they are investigating the Texas crash. Moravy said on Monday's call that Tesla is working with government agencies as they investigate the crash.
Some details of the crash remain unknown. Moravy also said that they were not able to recover data from the SD card at the time of impact, but that local authorities are working on doing that.
On Tuesday, the Alliance for Automotive Innovation, which represents automakers such as Ford, GM, VW and Toyota, but not Tesla, released
driver monitoring safety principles for systems like Autopilot. The principles cover how consumers are informed about the systems, as well as driver warnings. The principles called for consideration of in-car, camera-based driver monitoring systems, which Tesla does not utilize.
Wade Newton, a spokesperson for the AAI said that it is the first time the industry has come together to introduce these types of principles, and declined to say if the Tesla crash impacted the release.