(Adds details, rivals including Airbus)
FRANKFURT, Sept 5 (Reuters) - Lilium, a German start-up with Silicon Valley-scale ambitions to develop a 5-passenger "flying taxi", has raised a second, $90 million round of financing from top tech investors, making it one of the best-funded electric aircraft projects to date.
The company has emerged as one of Europe's hottest start-ups as it looks to create a new category of aircraft capable of both vertical take-off and electric powered jet flight.
Lilium said on Tuesday the new funding, led by Chinese internet giant Tencent, also includes Liechtenstein-based LGT, Europe's largest family-owned investment firm; European venture firm Atomico; and Obvious Ventures, whose co-founder, Evan Williams, is a co-founder of Twitter.
Long the stuff of science fiction and futuristic cartoons such as "The Jetsons", aviation and technology leaders are now racing to develop new types of electric-powered flying vehicles, dubbed "flying cars", including Airbus, Uber and a range of start-ups including one backed by Google co-founder Larry Page, called Kitty Hawk.
In April, Lilium said it was developing a five-seat "flying taxi" after mounting successful test flights of a full-size, two-seat jet capable of a mid-air transition from hover mode, like drones, to wing-borne flight, like conventional aircraft. (http://reut.rs/2eVAcU4)
Wing-borne, electric-powered flight allows commuter aircraft to travel five or six times the distance of drones, a Lilium executive said. A 20-km (12-mile) trip from Manhattan to JFK Airport could take as little as five minutes, he estimated.
"The concept goes far beyond what you typically see from German start-ups," said Remo Gerber, the former European managing director of online taxi firm Gett, who was named Lilium's chief commercial officer last month.
Lilium said it plans to use the new funds to expand hiring and carry it through the next development stages of its 5-seater electric jet, buying it time to meet stringent regulatory approvals.
The 70-employee company has roughly as many outstanding job postings as current staff, and plans to rapidly scale up hiring of aeronautical engineers, physicists, computer science and electric propulsion experts, Gerber said.
Lilium, which was founded in 2015 by four graduates from the Technical University of Munich, is shooting for a manned test flight of its five-seat aircraft around 2019, and to roll-out "flying taxi" commuter services, subject to regulatory approvals, some time in the next decade.
The lightweight aircraft will be powered by 36 electric jet engines mounted on its wings via 12 moveable flaps. With a range of 300 km and cruising speed of 300 km per hour, Lilium will be the only electric aircraft capable of both vertical take-off and jet-powered flight, the company said.
Combining these two features is what separates Lilium from rival start-ups working so-called flying cars or taxis that rely on drone or helicopter-like technologies, such as German rival Volocopter or European aerospace giant Airbus.
The Larry Page-backed Kitty Hawk is an all-electric personal aircraft that can be operated over water without a pilot's licence, which the Silicon Valley company said in April it plans to launch this year. (https://kittyhawk.aero/about).
Airbus aims to test a self-piloted flying car in 2017 and is exploring a helicopter-style vehicle capable of carrying multiple passengers over cities. (http://reut.rs/2eXTgAZ)
Volocopter GmbH, a startup based south of Heidelberg, has won certification for an electric-powered two-seat helicopter to conduct manned flights tests in Germany. It plans autonomous air taxi test flights in Dubai later in 2017.
"Autonomous transport will come faster in the air. There are fewer objects to navigate, requiring less complex sensors and software than when compared to a car operating in an area with pedestrians," Volocopter Chief Executive Florian Reuter said in a recent interview. (Additional reporting by Edward Taylor in Frankfurt; editing by Stephen Coates and Jason Neely)