IT may sound like something out of a sci-fi movie, but competition is heating up between firms desperate to become the first to introduce on-demand air taxis to revolutionise the way we live and travel.

Flying taxis?

Not your typical black or yellow cabs, of course, but - depending on the firm - either large drones or small jets.

To carry people?

Chinese firm Ehang builds drones big enough to carry human passengers. The firm has just filed paperwork with the US Securities and Exchange Commission to go public, offering $100 million shares to raise new equity.

But this is all years away from fruition?

Not so. Ehang says it plans to launch the world’s first autonomous air taxi service in the coming months.

There are other firms aiming to be first?

Around 20 companies are in the market, which Morgan Stanley estimates will be worth around $850 billion within 20 years.

Who are they?

Germany’s Lilium is behind the all-electric Lilium jet. With top speeds of 300km-per-hour and a range of 300km, it takes-off and lands vertically and fits five passengers. The firm wants commercial services to take flight in "several locations worldwide" by 2025.

The others?

Google’s billionaire founder, Larry Page, is backing Kitty Hawk, a firm operated by the team behind Google’s autonomous car. Airbus and Boeing are also developing projects.

Uber?

It’s developing an air taxi service that it plans to launch within the next three years in Los Angeles and Dallas in the US, as well as in Melbourne, Australia. The firm is working with Nasa and the US army on its flying taxis and is opening a laboratory in Paris to develop them.

But it all just sounds like the movies?

It easily brings to mind Marty McFly in 1985’s Back to the Future, with Michael J Fox taking to the sky in a Delorean, or what about the flying police cars in 1982's Blade Runner?

And Chitty Chitty…

..Bang Bang indeed. The magical car from the 1968 movie, co-written by Roald Dahl and loosely based on Ian Fleming's novel of the same name, certainly gets an honourable mention.

The benefits?

Relieving society from traffic and its environmental impact, allowing people to reach destinations far faster and changing options on how we live by offering to make commuting no big deal, for example, easing pressure on congested cities.

But the practicalities?

Building solid jets at a sustainable production cost is challenging, as is regulation and safety in the skies, as well as consumer affordability.

Hopes remain high, however?

Developers believe increased air mobility will address pressing issues in a world where population growth is leading to increased pressure on infrastructure.

Lilium founde, Daniel Wiegand, told the Web Summit in Lisbon this week that “this is why there is a desperate need for something that connects us faster…And this is why we think there is such a demand for something like we do.”

MAUREEN SUGDEN