A single-vehicle collision final month involving a Tesla Semi electrical truck took 50,000 gallons of water to extinguish and required plane to dump hearth retardant overhead, in accordance with a preliminary report on Friday from the Nationwide Transportation Security Board.

The crash, which occurred on California’s Interstate 80 west of Lake Tahoe, is being investigated by the NTSB. CAL-Fireplace’s efforts put out the flames cooled the automobile’s huge battery to maintain it from reigniting and prevented the hearth from spreading past the crash web site, the NTSB stated.

The Tesla truck, pushed by an worker, was headed to the corporate’s battery manufacturing unit in Sparks, Nevada, from a warehouse in Livermore, California, the report stated. The incident closed down a part of the I-80 for 15 hours.

Tesla CEO Elon Musk first confirmed off the Semi truck design at an occasion in November 2017, promising it could come to market in 2020. The corporate nonetheless hasn’t began producing the vans in excessive quantity, but it surely’s constructing out manufacturing strains at its Nevada facility.

“Preparation of Semi manufacturing unit continues and is on monitor to start manufacturing by finish of 2025,” Tesla stated in its second-quarter earnings report in July.

The NTSB report confirmed that Tesla’s driver help programs, that are marketed as Autopilot and Full Self-Driving (Supervised) within the U.S., weren’t “operational” on the time of the Semi collision and hearth.

Tesla did not reply to a request for remark.

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