As investigators examined audio recordings to determine what caused a small plane to crash in a residential East Palo Alto neighborhood, authorities Thursday tentatively identified the three employees of Tesla Motors Inc. who died.
The pilot was Doug Bourn, 56, a senior electrical engineer who had worked for the electric carmaker for five years and who mentored others.
The company said Bourn, a flight instructor, loved flying.
Also onboard the twin-engine Cessna 310 was Brian Finn, 42, a senior interactive electronics manager, who started working for Tesla in July 2008.
"He brought overriding optimism and a pioneering spirit" to the company, said Elon Musk, Tesla's chief executive, on a company blog.
The third employee, Andrew Ingram, 31, an electrical engineer with Tesla for 2 1/2 years, "was passionate about electronics and exquisite audio systems, and was eager to lend a hand wherever it was needed, from marketing to manufacturing," Musk wrote.
Authorities said no distress signal came from the plane before it ran into electrical transmission lines and shed parts over blocks of a low-income neighborhood shortly after taking off about 8 a.m. Wednesday.
With visibility at one-eighth of a mile and a cloud ceiling of 100 feet, Bourn received authorization to fly using instruments.
The loss of the three men was expected to take a practical as well as emotional toll on Tesla, which is based in nearby San Carlos and has 500 employees.
In such a small company, the three probably took on responsibilities outside of their job descriptions, said Dennis Virag, president of the Automotive Consulting Group in Ann Arbor, Mich.
"Although they weren't executives in the company, these three guys are the type of guys who were doing the work, who were doing the innovative stuff that makes Tesla what it is," Virag said. "Not all electrical vehicles are the same. In fact, they could differ considerably depending on the company."
The investigation into what caused the crash is expected to be aided by "very clear and quite powerful" audio recordings of the plane going down, said East Palo Alto Mayor Ronald Davis.
The crash damaged four structures, destroying one home, and burned five vehicles. Nobody on the ground was injured.