Even from a few hundred yards away, the aircraft made a noise strikingly different from the roar of a typical plane.
"It sounded like an electric motor running, just a high-pitched whine," said Steve Eggleston, assistant manager at an airplane-parts company with offices bordering the Hollister Municipal Airport.
But it wasn't only the sound that caught the attention of Eggleston and his co-workers at DK Turbines. It was what the aircraft was doing.
"What the heck's that?" saleswoman Brittany Rodriguez thought to herself. "It's just hovering."
That, apparently, was a flying car, or perhaps a prototype of another sort of aircraft under development by a mysterious startup called Zee.Aero. The company, one of two reportedly funded by Google co-founder Larry Page to develop revolutionary forms of transportation, has set up shop in rural Hollister, far from its Mountain View headquarters and the prying eyes of tech-obsessed Silicon Valley.
The secretive company, in its quest for privacy, has found allies in the small San Benito County town.
"Can I help you?" a woman from the airport's administration office said, after popping out to investigate when a reporter and photographer came looking for staff at the Zee.Aero building next door. "They're not here," she said curtly. Asked when they were typically around, she snapped, "That's private."
In Hollister, population 40,000, the first rule about Zee.Aero is you don't talk about Zee.Aero.
"It was known they wanted their privacy," said Hollister Mayor Ignacio Velazquez, who declined to provide much information about Zee.Aero and its plans. "I just believe in people's privacy."
For a while, staff at one airport business said, a guard was posted outside the Zee.Aero building, telling people who approached too closely to back off. When Eggleston first attempted to take photos of the aircraft being towed, its handlers took action, he said.
"They pulled a truck right in front of me," Eggleston said.
The company has issued no public statements about its work. Bloomberg in June reported that Page had invested more than $100 million in the startup but had tried to keep his involvement secret. Zee.Aero's sparse website refers to "a revolutionary new form of transportation." In a May letter to the U.S. Department of Transportation, the firm said it was building "an entirely new aircraft that will change personal aviation."
A Zee.Aero spokeswoman said the firm is "currently not discussing (its) plans publicly."
However, a Zee.Aero patent issued in 2013 describes in some detail an aircraft capable of the hovering seen by people working at the airport. And the drawings showcase a vision of the future in which flying cars park in lots just like their terrestrial, less-evolved cousins.
With traffic congestion costing the U.S. economy more than $120 billion annually and Americans collectively spending 8 billion hours a year stuck in traffic, according to transportation research firm Inrix, lifting off and cruising above snarled roadways has considerable appeal.
Zee.Aero envisions our means of escape from the bounds of gravity as "safe, quiet, and efficient, as well as easy to control, (and) highly compact," according to the patent submission from Ilan Kroo, a Stanford University professor of aeronautics and Zee.Aero's founding CEO and principal scientist. Kroo brought in more than 100 aerospace engineers to work on the flying cars, according to his LinkedIn profile.
The patent depicts a car-sized aircraft, wings at the nose and tail, and along the top eight propellers, driven by eight motors, for vertical lift. Two other propellers on the rear wing would provide forward thrust. The aircraft seen at the Hollister airport appears to showcase a change in design but retains some features described and shown in the patent.
Last week, an aircraft was spotted being towed down the runway on two consecutive days, although no hovering or flying was observed by witnesses. Dual propellers in the rear fit with the description and drawings from the patent, but the aircraft appeared to have a single main wing, with pod-like structures beneath it, rather than the smaller wings at the front and rear shown in the drawings. The means for vertical takeoff were not visible from a distance, but Eggleston and his colleagues said this was the same craft they'd seen hovering.
In May, the city of Hollister approved a 34-year lease with Zee.Aero for just under an acre of land near the intersection of the municipal airport's two landing strips. According to city documents, the company plans to build a 14,000-square-foot hangar and office building, plus nearly 10,000 square feet of employee parking and 16,000 square feet of paved area for aircraft parking and movement.
During both Zee.Aero flights witnessed by DK Turbines staff from several hundred yards away in September and October, the aircraft hovered about 25 feet off the ground, and landed rapidly, straight down, according to the witnesses. "My initial thought was it was some kind of experiment," said Saul Gomez, who works in inventory and sales, and described the hovering craft as white, slightly smaller than a Cessna and "like something out of a movie."
Zee.Aero has built nine aircraft and registered them with the Federal Aviation Administration, according to FAA records. Two are electric-powered gliders. Two are piston-powered, fixed-wing, kit-built planes. The five remaining most closely match Zee.Aero's patent for a "personal aircraft" with multiple motors - two of them are eight-motor "rotorcraft" and three are dual-motor, fixed-wing aircraft. But these aircraft are in fact electric-powered drones weighing 55 pounds or less and may be the company's reported prototypes.
Hollister Councilman Victor Gomez, who commutes to work in the Bay Area, would like to see Zee.Aero succeed.
"Oh, man, how much I would love to find another route other than Highway 101 to get to work," Gomez said. "It's exciting to see something that's so innovative. I'm thrilled about the concept. It is something to be expected from Larry Page and people in that area."
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