Bourn and two fellow Tesla employees died in a fiery crash in an East Palo Alto neighborhood after their twin-engine Cessna took off in heavy fog and suddenly veered to the left, striking high-tension powerlines and a tower before crashing into an East Palo Alto neighborhood and causing a 10-hour power failure in Palo Alto.
The recordings, released by the Federal Aviation Administration at the request of the San Jose Mercury News, detailed that air-traffic controllers felt fog-related visibility was so risky they told Bourn they would not take responsibility for Bourn's plane or his two passengers.
The recordings initially capture the usual protocols for flights. A controller reviews Bourn's flight plan for the trip to Hawthorne, Calif. He was to "turn right heading 060 within 1 mile," the controller said. Bourn can be heard confirming the plan.
Bourn was then released for takeoff, with a caveat.
"We have your release and the runway is not visible so it's at your own risk," a controller matter-of-factly told Bourn.
After a 30-second silence, the controller told Bourn the release was only valid for two minutes.
"OK. I, uh, did not hear that I'm cleared for takeoff," Bourn said.
"I cannot clear you for takeoff because I don't have visibility on the runway so the release is all yours and it's at your own risk, sir," the controller said.
"OK. 25 Juliet, rolling," Bourn replied.
The plane took off but quickly dropped off the radar screen. Controllers at Palo Alto Airport, Moffett Field in Mountain View and Norcal TRACON tried to reach Bourn by radio. There was no response.
"Twin Cessna 25 Juliet, contact Norcal Departure. ... Twin Cessna 25 Juliet, contact Norcal Departure. ... Twin Cessna 25 Juliet, contact Norcal Departure," the controllers repeated over a 42-second period, while an alarm beeped insistently in the background.
Then power failed in the control tower.
Palo Alto Controller 1: "Airport One, Palo Alto Ground. ... We have a full power loss up here."
Airport One: "Yeah, it looks like the whole airport the power's out. The beacon's not on right now. ..."
Palo Alto Controller 1 to Moffett controller: "Yeah, we have a full power loss right now and if you can get ahold of them tell them we have a report that they may have been crashed off the end of our runway."
Moffett and Palo Alto controllers exchanged information that neither they nor Norcal TRACON could raise Bourn on communication channels.
Palo Alto Controller 1: "I keep trying to call them."
Moffett: " ... You guys need to get out there to the end of the runway to see it..."
Bourn's plane had veered sharply to the left and struck a high-tension tower and power lines shortly after takeoff and then broke apart and crashed in flames into the Beech Street residential neighborhood in East Palo Alto.
Several homes were damaged, including one that was destroyed, as were a number of vehicles. No one on the ground was injured, although some narrow misses were reported.
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Listen to the audio recordings: Pilot Doug Bourn confirms flight plan with Palo Alto air-traffic controller; Palo Alto air-traffic controller issues the release for Bourn's take-off but says it's 'at your own risk' (recording includes 30 seconds of silence); Palo Alto and Norcal TRACON controllers try to communicate with Bourn; Palo Alto and Moffett Field air-traffic controllers fear the plane has crashed