Vertical Aerospace, a global leader in pioneering electric aviation, has achieved a pivotal milestone by receiving its Permit to Fly from the UK Civil Aviation Authority (CAA). This regulatory approval authorizes the Company to commence ‘Phase 4 – Transition’ flight testing, the final stage of its VX4 prototype flight-test programme. This phase is dedicated to testing the aircraft’s defining manoeuvre: seamlessly shifting between hover, or “helicopter mode,” and efficient wingborne flight, or “airplane mode.”
The inaugural flight of this critical phase was successfully piloted by Paul Stone on 13 November 2025. This transition flight testing represents the culmination of a rigorous flight-test programme, building upon the successful completion of Phases 1-3 earlier in the year. Those initial phases confirmed the VX4’s exceptional flying qualities and included its first flights in open airspace.
Preparation for this milestone involved extensive collaboration with the UK CAA. Vertical’s engineering and test teams completed comprehensive simulation, ground, and flight testing to verify all 200 Minimum Safe Aircraft requirements. This robust approach to certification was supported by the submission of over 20,000 pages of updated safety and technical information to the regulator. The CAA is also working closely with the European Union Aviation Safety Agency (EASA) for the concurrent validation and certification of the VX4, ensuring it meets the highest safety standards required for future commercial use.
CEO Stuart Simpson hailed this as a “defining moment for Vertical Aerospace.” He emphasized that the team’s months of diligent work under close regulatory oversight reflect the Company’s unique and rigorous certification strategy. This step is a critical technical and certification unlock, demonstrating the real-world capability of the VX4’s unique tiltrotor technology.
The announcement follows the Company’s recent Q3 Business & Strategy update, where it shared an animation of the transition manoeuvre and offered a first look at its new certification aircraft’s leading cabin, highlighting its significant size and comfort. This progress marks a significant leap forward in Vertical’s mission to redefine urban air mobility.
