While the agency has yet to make a determination, an attorney representing Huang's family asserted in a letter last year that the vehicle's Autopilot had been a problem, particularly at the location of the crash. Huang reportedly told his wife, Sevonne, and a friend that his vehicle's lane-keeping technology was problematic and had a tendency to steer toward the median, also known as the gore point.
"Walter told Sevonne the Autopilot would cause his Tesla to veer toward the barrier involved in his crash, prior to the crash," according to Mark Fong, an attorney with Minami Tamaki.
Tesla representatives did not immediately respond to requests for comment.
Vehicle maintenance records show that, two weeks prior to the crash, Huang brought his car to a Sunnyvale service center reporting problems with his GPS and navigation system that prevented his cruise control from functioning. A service advisor reportedly was unable to duplicate the problem during the visit, and had "no recollection whether the driver told him about problems encountered while driving vehicle in the vicinity of the gore area on US-101," according to the documents.
An earlier report released by NTSB found that the Tesla's Autopilot system, shorthand for a suite of functions including adaptive cruise control and autosteer lane-keeping assistance, was enabled at the time of the crash. Huang's vehicle was in a lane traveling south on Highway 101 when it moved left and sped up from 62 mph to 70.8 mph. No "precrash braking or evasive steering" movement was detected.
The severe damage to the Tesla breached the battery, causing it to catch fire shortly after the crash. Though bystanders were able to pull Huang from the vehicle just before it was engulfed in flames, he later died of his injuries.
NTSB will be holding a board meeting on Feb. 25 to determine the probable cause of the fatal crash. In a previous report, the agency slammed Caltrans for "systemic problems" that prevented the swift repair of traffic safety equipment that could have lessened the severity of the crash. Caltrans is responsible for maintaining a crash attenuator at the site of the collision, which is equipped with a hydraulic cylinder and cable assembly designed to "telescope" and absorb impact when a vehicle hits it at high speeds.
The attenuator located at the highway median had been smashed by a Prius in a solo-vehicle accident 11 days before the Tesla crash and was damaged to the point of being "nonoperational," and had not yet been replaced.
Alongside the NTSB investigation, Huang's family has also filed a wrongful death suit in Santa Clara County Superior Court. The suit alleges that Autopilot, while marketed as safe features designed to prevent crashes, should have prevented Huang's Model X from accelerating into a fixed object on the road.
The full public docket released by NTSB can be reviewed online at go.usa.gov/xd9u9.
This story contains 573 words.
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