Vertical Aerospace, the NYSE-listed electric aviation company, has completed what it describes as a historic first in aviation: a piloted thrustborne transition in a full-scale electric vertical take-off and landing (eVTOL) aircraft.
The milestone, achieved on 2 April at Cotswold Airport, saw test pilot Paul Stone fly the company's Valo aircraft vertically into the air before its front propellers tilted forward, accelerating the aircraft into conventional wingborne flight, with the rear propellers stowing during the transition.
Vertical says the achievement is the most significant technical milestone in its ten-year history and marks completion of the first half of what it calls the two-way transition sequence, in which an aircraft takes off vertically, flies on the wing, and then decelerates to land vertically, without requiring a runway.
The company says the flight was conducted under strict oversight of the UK Civil Aviation Authority (CAA), which is working in close collaboration with the European Union Aviation Safety Agency (EASA) toward certification of Valo, and that it is the first such piloted transition by a full-scale eVTOL aircraft of this class to be performed under that regulatory framework.
Thrustborne transition refers to the process of transferring lift from propellers to wings mid-flight, which Vertical describes as one of the most complex challenges in aviation, requiring the aircraft to move seamlessly between two fundamentally different modes of flight in real-world conditions.
The announcement follows Vertical's disclosure on 30 March that it had agreed in principle a financing package of up to $850 million, intended to provide immediate capital and access to additional flexible funding as the company progresses toward type certification and commercial operations.
Chief executive Stuart Simpson said the achievement demonstrates that Vertical has "solved the hardest engineering challenges" and now has both the regulatory relationships and financial foundation to reach commercial service.
Chief engineer David King said the aircraft "performed exactly as designed, transitioning smoothly and under full control," describing the result as proof of the core elements of Vertical's distributed electric propulsion and tiltrotor technology at full scale.
Stone, the test pilot, said the aircraft's response during the transition matched simulation predictions precisely, calling the engineering team's work "genuinely extraordinary."
The flight builds on nearly two years of piloted testing, during which the aircraft has demonstrated hover, vertical take-off, wingborne flight, and vertical landing, including what Vertical says was the first winged eVTOL flight in open European airspace and an airport-to-airport flight at the Royal International Air Tattoo.
Vertical says it is now expanding the transition envelope from both directions, accelerating from hover and decelerating from wingborne flight, with the remaining step being the deceleration-to-landing sequence required to complete the full two-way transition.
Each stage of testing is conducted under a Permit to Fly regime, with structural testing, systems validation, and simulator work submitted to regulators before further envelope expansion is permitted.