April 25, 2026

6 min read

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An electric air taxi passes its hardest test. When can passengers fly?

A British start-up recently pulled off a key maneuver for electric vertical flight—but certification, infrastructure and demand will decide whether air taxis fill our skies

By Deni Ellis Béchard edited by Eric Sullivan

Vertical Aerospace’s VX4 electric aircraft flies during a piloted transition test flight on April 14, 2026.

Vertical Aerospace

On the morning of April 14, 2026, at Cotswold Airport in southwest England, a test pilot rose straight into the air. He was testing the VX4—an electric vertical takeoff and landing (eVTOL) aircraft, or air taxi—built by the British firm Vertical Aerospace. During the test, the VX4’s eight propellers lifted it like a drone. Then the four front propellers tilted forward, and the aircraft accelerated, no longer hanging on its rotors like a helicopter but cruising on its wings like a small airplane. Moments later, it reversed the sequence: the propellers tilted back up, and the aircraft decelerated, returned to a hover and landed vertically on the same pad it had left.

In completing this test, Vertical—founded in 2016 and based in Bristol—accomplished one of the hardest feats in eVTOL development: its prototype changed from flying like a helicopter to flying like an airplane, then back again. But a prototype is allowed to fly because a regulator has agreed it is safe enough to test. A certified commercial aircraft, meanwhile, has to be safe enough for strangers to buckle their children into it.

Vertical is among the first Western developers to demonstrate piloted transition, but the April flight also matters because of the regulatory context. Other developers have flown to prove the technology works; Vertical is trying to build a case for certification. “The significance of this flight is that it has been achieved in a way that is aligned with the certification pathway from the outset,” says David King, Vertical’s chief engineer. In other words, Vertical is getting closer to the actual business of running an air taxi company.

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King’s journey to eVTOLs began with his work at Boeing in 1989, on a military aircraft called the V-22 Osprey. The Osprey was the first production tiltrotor—an aircraft with propellers that can swivel on their mounts, pointing up for vertical takeoff and tilting forward for horizontal flight. For most of the next three decades, at Bell and then at Italian aerospace firm Leonardo, King worked on civil tiltrotors, the passenger-carrying cousins of the Osprey.

Vertical Aerospace’s Valo, the company’s planned commercial eVTOL aircraft and successor to the VX4 prototype. Vertical unveiled the aircraft in December 2025.

Vertical Aerospace

King decided to join Vertical in 2023 because the VX4 is essentially a tiltrotor with electric motors. “The beauty of the tiltrotor is it takes you less than a minute from the time you apply power to cruising on a wing,” he says. “The basic magic of being able to transition from thrustborne to wingborne is proven.” What remains is to tune the system to carry different loads in varied weather and on different routes.

Daniel Pleffken, an assistant professor at Embry-Riddle Aeronautical University in Florida, who specializes in aircraft certification, is more measured about what the flight proves. “A successful flight shows that something can work,” he says. “Certification requires proving that it works safely, consistently and under all expected conditions.” The aircraft still must accumulate evidence from failure tests, repeat flights and design reviews before regulators will let it carry passengers.

Vertical’s situation is unusual. Since 2023 the U.K. Civil Aviation Authority (CAA) has overseen every test flight of the VX4. Most eVTOL companies fly their prototypes under research flight licenses, but the data they produce don’t count toward certification. Vertical flies under an arrangement that has been accumulating evidence toward certification for three years. “We are demonstrating to the regulator that we have the engineering capability, design assurance processes and internal governance required for full type certification,” King says.

Vertical Aerospace displays its Valo electric aircraft at the company’s London launch event.

Vertical Aerospace

The other two Western developers that have flown piloted transitions, California-based Joby Aviation and Vermont-based BETA Technologies, have done so under the U.S. Federal Aviation Administration&rs