SAN FRANCISCO — Flying cars are just starting to inch their way out of science fiction. But that is not stopping some companies from planning for flying taxi services.

A growing collection of tech companies, aircraft manufacturers, automakers and investors are betting that fleets of battery-powered aircraft will give rise to air taxi services, perhaps as soon as the next decade. Some of those taxis, the companies hope, may even use artificial intelligence to fly themselves.

The dealmaking, technology exploration and perhaps wishful thinking around this new sort of flying transportation — please, the companies ask, don’t call them flying cars — are reminiscent of the work done on self-driving cars just a few years ago.

No one can say for certain if these new vehicles will turn out to be a real business. But many companies are already worried about being left behind.

The European aerospace company Airbus said Tuesday that it was making an investment in Blade, an aviation startup in New York, and forming a partnership to expand Blade’s helicopter hailing service in more cities around the world. Last week, Dara Khosrowshahi, Uber’s chief executive, said he expected the ride-hailing company to start flying passengers on a service called Uber Air in five to 10 years.

In November, Boeing acquired Aurora Flight Sciences, a company specializing in flight systems for pilotless aircraft, for an undisclosed sum. Before the acquisition, Aurora had been working with Uber to develop a flying taxi. And Joby Aviation, a startup in Santa Cruz, California, building its own air taxi, said this month that it had raised $100 million in venture funding from a consortium of investors including the venture capital arms of Intel, Toyota Motor and JetBlue Airways.

“This is the natural progression of the vehicles we make,” said Ben Bridge, head of global business for Airbus Helicopters. “We want a seat at the table and a voice in the conversation that is happening.”

Flying cars even played a bit role in the recently settled legal fight over trade secrets between Uber and Waymo, the self-driving car service spun out of Google.

In court testimony this month, Travis Kalanick, Uber’s former chief executive, said he had heard that Larry Page — the chief executive of Waymo’s parent company, Alphabet, who has a side project building new types of aircraft — was upset because Uber was “doing their thing” with flying cars.

Whatever you imagine a flying car to be — stop. What these companies envision is something like a helicopter but much quieter and more affordable. Think of a hobbyist’s drone, but big enough to fit people. It would, in theory, be welcome in urban environments and affordable to more than well-heeled business people. At least, that’s the dream.

Rendering from Lilium

Before there can be too much enthusiasm for these flying taxi services, it’s worth noting that self-driving cars have yet to turn into a notable business for anyone, despite about a decade of research at tech giants like Google and billions in investment from Silicon Valley and the auto industry.

Regulators are just starting to agree on rules for large-scale tests of self-driving cars on public roads. How would they deal with flying taxis? The details of the future service are far — very far — from being ironed out.

Still, there are some reasons for the new enthusiasm. Battery improvements and the wide use of drones have spawned technological breakthroughs. The taxis would take off and land vertically like a helicopter, so they’d take up less room. Because they would be battery-powered, they would be more environmentally friendly.

For now, Airbus executives hope to gain from Blade’s experience with an app that allows customers to reserve a seat on a helicopter. Airbus is expected to invest up to $15 million in Blade, which would represent about a 10 percent stake in the company, according to a person who is familiar with the transaction but not permitted to discuss the investment details publicly.

Both companies see helicopters as an intermediate step until a new type of aircraft and taxi service hits the market. Rob Wiesenthal, Blade’s chief executive, said a quieter and less expensive alternative to helicopters “opens up a whole new world.”

Airbus said it was preparing for a test flight by year-end for its CityAirbus aircraft, which carries up to four passengers and can reach a cruising speed of about 75 mph. It plans to deploy the CityAirbus in 2023. Uber has said it expects to begin testing of its urban air taxis in the Dallas-Fort Worth area, Los Angeles and Dubai in 2020. The company has landed exclusive deals for vertical takeoff and landing spots with real estate companies, including in the Dallas-Fort Worth area.

Uber declared its interest with its Uber Elevate initiative in 2016, forecasting a future when it could offer 15-minute Uber Air rides from San Francisco to San Jose for $20. The 50-mile ride with Uber Pool, its car-pooling option, usually takes about two hours in rush-hour traffic and costs $83.

It did not put a date on that future.

In a concept video for Uber Elevate, a woman opens the Uber app, which gives her a choice of taking a ride with Uber Pool, UberX or Uber Air. She enters a nearby building and rides the elevator to the top floor, where she boards an air taxi in Uber Skyport.

Uber is also establishing performance guidelines for its flying taxis, including asking that the new aircraft make only one-quarter of the noise of a small four-seat helicopter. Uber also has supplier deals in place with five manufacturers, including Textron’s Bell Helicopter.

“We believe the best way to get this idea off the ground is to partner with world-class companies and stakeholders that have a diverse set of specializations,” an Uber spokesman, Matt Wing, said in a statement.

Daniel Wiegand, a co-founder and the chief executive of the German air taxi company Lilium, said investors considered him totally crazy when he pitched the company in 2015.

“It has completely changed,” Wiegand said. Like many of his competitors, he dismisses the phrase “flying cars” because other companies are working on cars that fly as well as drive on the road. In September, Lilium announced that it had raised $90 million from investors, including the Chinese internet giant Tencent.

And then there is Google — or, to be more specific, Page, Google’s co-founder and Alphabet’s chief executive. He has invested part of his personal wealth in Kitty Hawk, a startup that has demonstrated a personal aircraft that flies using propellers over water. A Kitty Hawk division called Zee Aero is also reportedly working on an air taxi concept aircraft.

Kalanick said he told Page that he believed a flying service “sounds pretty cool,” even though Uber wasn’t building one. But once the aircraft are available, he said, “I will make sure that our 50 million or so customers at the time can push a button and get a flying car.”