For now, nobody believes people are going to be zipping around in flying cars any time soon. Many hurdles remain, such as battery life, the need for regulations and of course safety concerns. But dozens of such projects are popping up around the world.

A flying car is defined as aircraft that is electric, or hybrid electric, with driverless capabilities, that can land and take off vertically, according to Ebihara.

These are often called EVtol, which stands for “electric vertical take-off and landing” aircraft. All the flying car concepts, which are like drones big enough to hold humans, promise to be better than helicopters, which are expensive to maintain, noisy to fly and require trained pilots, Ebihara and other proponents said.

“You may think of Back to the Future, Gundam or Doraemon,” Ebihara said, referring to vehicles of flight in a Hollywood film and in Japanese cartoons featuring robots. “Up to now, it was just a dream, but with innovations in motors and batteries, it’s time for it to become real,” he said.

US internet giant Google, Germany’s Volkswagen, Chinese drone company Ehang and car manufacturer Geely have invested in flying car technology.

Nissan Motor and Honda Motor said they had nothing to say about flying cars, but Toyota Motor Corp recently invested US$500 million in working with Uber Technologies on a self-driving system for the ride-hailing service. Toyota group companies have also invested 42.5 million yen (US$375,000) in a Japanese start-up, Cartivator, that is working on a flying car.

The hope is to fly up and light the torch at the 2020 Tokyo Olympics, but it is unclear Toyota will meet that goal. At a demonstration last year, the device crashed after it rose to slightly higher than eye level. A video of a more recent demonstration suggests it is now flying with more stability, although it is being tested indoors, unstaffed and chained so it will not fly away.

There are also plenty of sceptics.

Elon Musk, chief executive of electric car maker Tesla, has said that even toy drones are noisy and blow a lot of air, which means anything that would be “1,000 times heavier” is not practical.

“If you want a flying car, just put wheels on a helicopter,” Musk said in a recent interview with podcast host and comedian Joe Rogan on YouTube. “Your neighbours are not going to be happy if you land a flying car in your backyard or on your rooftop.”

Though the Japanese government has resisted Uber’s efforts to offer ride-hailing services in Japan, limiting it to partnerships with taxi companies, it has eagerly embraced the US company’s work on EVtol machines.

Uber said it is considering Tokyo as its first launch city for affordable flights via its UberAir service. It said Los Angeles and Dallas, Texas, and locations in Australia, Brazil, France and India are other possible locations for its services.

Unlike regular aeroplanes, with their aerodynamic design and two wings, Uber’s “Elevate” structures look like small jets with several propellers on top. The company said it plans flight demonstrations as soon as 2020 and a commercial service by 2023.

Uber’s vision calls for using heliports on rooftops, but new multi-floored construction similar to car parks is likely to be needed to accommodate so many more EVtol aircraft, once the service takes off.

Unmanned drones are legal in Japan, the US and other countries, but there are restrictions on where they can be flown and requirements for getting approval in advance. In Japan, drone fliers can be licensed if they take classes. There is no requirement like drivers licences for cars.

Flying passengers over populated areas would take a quantum leap in technology, overhauling aviation regulations and air traffic safety controls and major efforts both to ensure safety and convince people it is safe.

Uber said at a recent presentation in Tokyo that it envisions a route between the city’s two international airports, among others. Savings in time would add up, it said.

“This is not a rich person’s toy. This is a mass market solution,” said Adam Warmoth, product manager at Uber Elevate.

Concepts for flying cars vary greatly. Some resemble vehicles with several propellers on top while others look more like a boat with a seat over the propellers.

Ebihara, the flying-car chief at the Ministry of Economy, Trade and Industry, said Japan is on board for Blade Runner-style travel – despite its plentiful, efficient and well-developed public transport.

Japan’s car and electronics industries have the technology and ability to produce super-light materials that could give the nation an edge in the flying car business, Ebihara said. Such vehicles could be tested first in uncongested, remote areas or between islands, where public transport is less accessible and safety issues would be less of a problem.

Just as the automobile vanquished horse-drawn carriages, moving short-distance transport into the air could in theory bring a sea change in how people live, Ebihara said, pointing to the sky outside the ministry building to stress how empty it was compared to the streets below.

Flying also has the allure of a bird’s-eye view, the stuff of drone videos increasingly used in filmmaking, tourism promotion and journalism.

Atsushi Taguchi, a “drone grapher”, as specialists in drone video are called, expects test flights can be carried out even if flying cars will not become a reality for years since the basic technology for stable flying already exists with recent advances in sensors, robotics and digital cameras.

A growing labour shortage in deliveries in Japan is adding to the pressures to realise such technology, though there are risks, said Taguchi, who teaches at the Tokyo film school Digital Hollywood.

The propellers on commercially sold drones today are dangerous, and some of his students have lost fingers with improper flying. The bigger propellers needed for vertical flight would increase the hazards and might need to be covered.

The devices might need parachutes to soften crash landings, or might have to explode into small bits to ensure pieces hitting the ground would be smaller.

“I think one of the biggest hurdles is safety,” said Taguchi. “And anything that flies will, by definition, crash.”