Tesla Model S Autopilot 'Sped Up' Before Crashing Into Utah Firetruck

A Tesla Model S that was involved in a road traffic collision while set to autopilot mode earlier this month accelerated just prior to the crash, a police assessment report has revealed.

The incident, which occurred on May 11 in South Jordan, Utah, was reported by the local police department at the time. Officials said that the driver—named as Heather Lommatzsch—hit a vehicle belonging to the Fire Authority and had been looking at her phone in the minutes before impact.

Investigators now believe the Tesla sped up for just over three seconds before hitting the stationary firetruck, according to The Associated Press, which obtained the internal police document on Thursday. The main theory is that the Model S had reduced its speed from 60 mph to 55 mph to match a vehicle in front but sped up again automatically to the preset of 60 mph after the car ahead changed lanes.

On its website, Tesla says its autopilot—which is not intended as a way of avoiding a crash—is made to "detect objects that the car may impact" and help apply the brakes." The electric cars also come with front collision alerts to "help warn of impending collisions with slower moving or stationary cars."

Lommatzsch—who was described as 29 years old by The Associated Press but 28 by Utah police, said she thought the Tesla's braking system would have stopped the car before the crash took place. A witness at the scene was recorded as saying that the driver did not appear to hit the brakes.

According to a press release from South Jordan Police Department published on May 14, Lommatzsch was transported to a local hospital with a broken right foot. The driver of the Fire Authority vehicle was checked for injuries related to whiplash, but did not need additional care. In a final update, published May 16, Sergeant Samuel Winkler confirmed a Tesla investigation had already taken place.

The Elon Musk-led company said Lommatzsch had "engaged Autosteer and Traffic Aware Cruise Control on multiple occasions" and "repeatedly cancelled and then re-engaged these features" while travelling on the highway. It revealed that she had "manually pressed the vehicle brake pedal fractions of a second prior to the crash."

Tesla confirmed the speed was "around 60 mph" when the incident happened.

The data analysis stated: "The vehicle registered more than a dozen instances of her hands being off the steering wheel in this drive cycle. On two such occasions, she had her hands off the wheel for more than one minute each time and her hands came back on only after a visual alert was provided.

"Each time she put her hands back on the wheel, she took them back off after a few seconds," it added. "Contrary to the proper use of Autopilot, the driver did not pay attention to the road at all times, did not keep her hands on the steering wheel, and she used it on a street with no center median."

Musk took to Twitter after news of the crash broke to criticize the media. He said it was "super messed up" that it was being covered heavily by the press, when other road deaths were not. "What's actually amazing about this accident is that a Model S hit a fire truck at 60 mph and the driver only broke an ankle," the founder wrote. "An impact at that speed usually results in severe injury or death."

Earlier this month, Tesla told Newsweek that it would fully cooperate with authorities in Florida investigating a collision involving a Model S that resulted in the death of two teenagers. The vehicle, which was "engulfed in flames" after hitting a wall, likely did not have autopilot engaged, police said.