WASHINGTON -- An Uber autonomous vehicle that struck and killed a woman in Arizona in March failed to identify the pedestrian or to brake, raising serious questions about its performance, the National Transportation Safety Board said in a preliminary report released on Thursday.
The report said the vehicle's radar systems observed the pedestrian six seconds before impact but "the self-driving system software classified the pedestrian as an unknown object, as a vehicle, and then as a bicycle."
At 1.3 seconds before impact, the self-driving system determined emergency braking was needed, but Uber said emergency braking maneuvers were not enabled while the vehicle was under computer control in order to reduce the potential for erratic vehicle behavior.
Uber Technologies Inc., which suspended testing in the aftermath of the crash in the city of Tempe -- the first death ever from a fully self-driving vehicle -- said on Wednesday it would shut down its Arizona self-driving testing program and will focus on limited testing in Pittsburgh and two cities in California.
The company did not directly comment on the NTSB findings but noted that it recently named a former NTSB chairman, Christopher Hart, to advise on Uber's safety culture.
"As their investigation continues, we’ve initiated our own safety review of our self-driving vehicles program," the company said on Thursday, adding it planned to announce changes in the coming weeks.
The ride-hailing company aims to resume self-driving operations this summer, likely with smaller routes and fewer cars, the company said on Wednesday.