It's happening inside this building with the blacked-out windows, where no one gets inside without a special access code. Zee.Aero is working on a flying car. It has filed for a number of patents, which are public, but it turned down an interview, saying it's still in stealth mode.
The brains behind it is Stanford Aeronautics and Astronautics Professor Ilan Kroo, who is listed as the inventor on its patents.
A flying car? About 10 ambitious companies on two continents all have the same vision.
Video provided by Terrafugia of its flying car, called The Transition, shows it flying this summer in Indiana. CEO and co-founder Carl Dietrich is supportive of new competition from Mountain View's Zee.Aero.
"The more companies that we have that are all pulling in this direction of creating viable flying cars, the faster regulations will change and the faster society will adapt to this new technology," Dietrich said in a Skype interview.
The Transition is a street legal car, and the driver can fly with a sport pilot certificate. The base price is $279,000. Production is about two years off. It has a range of 100 miles and can fly at 100 miles per hour.
But the key to flying cars taking off will be computer-aided navigation so minimal aviation skills are required.
"Now that person doesn't necessarily need to have the traditional stick and rudder operating skill that a pilot today has to have, and they may not need to know about cloud clearance and visibility requirements and Class E airspace, which a pilot absolutely has to know," Dietrich said. "They don't need to know that because all of that is programmed into the vehicle."
Computer-aided flying cars are still in development. Another goal is vertical takeoff and landing, similar to helicopters, to free operators from having to use airports.
Many other concepts and designs are in the works and at various stages of development. And some day, the cloak of secrecy at this stealth operation might lead to a kittyhawk-like event.