Technology & Innovation
Vertical Aerospace Targets Full VX4 Transition Flight in Early 2026
Vertical Aerospace advances VX4 flight tests with 10 piloted flights completed; full transition now targeted for early 2026 amid regulatory updates.
This article is based on an official press release from Vertical Aerospace and includes analysis based on publicly available financial filings.
On December 19, 2025, Vertical Aerospace released a significant operational update regarding the flight testing of its full-scale VX4 prototype. According to the company, the engineering team has successfully completed 10 piloted test flights since receiving a “Permit to Fly” from the UK Civil Aviation Authority (CAA) in November. While the company reports expanding the majority of the flight envelope, the critical milestone of full piloted transition, switching completely from vertical hover to wing-borne cruise, has not yet been achieved.
The Bristol-based eVTOL (electric vertical take-off and landing) manufacturer stated that weather constraints and limited testing windows have pushed the target for full transition into early 2026. This update comes shortly after the company unveiled “Valo,” its production-intent aircraft, earlier this month.
Since resuming flight activities on November 13, 2025, Vertical Aerospace reports that the VX4 prototype has undergone rigorous testing to validate its handling and safety systems. The press release highlights that the aircraft has successfully performed acceleration and deceleration maneuvers and tested various tilt positions for its rotors.
According to Vertical Aerospace, the Test-Flights campaign has achieved several specific technical milestones:
The testing program has successfully validated the in-flight deployment and stowing of rear propellers, propeller spin-up during wing-borne flight, and “prop-hold” functionality.
The company notes that the “majority of the transition envelope” has now been expanded, leaving only the final 10% of the tilt transition untested. The completion of this final phase is required to demonstrate the aircraft’s ability to fly purely on wing lift, a defining characteristic of viable eVTOL technology.
Alongside the flight test updates, Vertical Aerospace announced a regulatory achievement involving the UK Civil Aviation Authority (CAA). The Regulations has granted the company new privileges allowing it to approve its own “Flight Conditions” and issue Permits to Fly for specific scenarios.
In the press release, the company framed this development as a signal of regulatory confidence in their design and engineering processes. This authorization is expected to streamline future testing phases by reducing the administrative lead time required for certain flight approvals. It is important for industry observers to distinguish between the aircraft currently undergoing testing and the product Vertical Aerospace intends to bring to market. The operational update refers specifically to the VX4 prototype, which serves as a testbed for data gathering. However, the commercial future of the company rests on “Valo,” the production model unveiled around December 10, 2025.
While the VX4 validates the core physics and control laws, Valo features a redesigned airframe, updated wing architecture, and an under-floor battery system. The delay in the VX4’s full transition means that critical aerodynamic data needed to finalize Valo’s Certification profile, targeted for 2028, will not be fully available until the prototype completes its envelope expansion in 2026.
The delay of the full transition flight places Vertical Aerospace behind its primary United States competitors in terms of technical milestones. Competitors such as Joby Aviation and Archer Aviation successfully completed full piloted transition flights earlier in 2025. Furthermore, the European market saw a significant contraction earlier this year with the reported insolvency of Lilium in February 2025, highlighting the capital-intensive nature of the sector.
Financial-Results sustainability remains a key focus for Vertical Aerospace. According to the company’s Q3 2025 Business & Strategy Update, Vertical reported a cash position of approximately $117 million. Based on current burn rates, the company projects this capital will fund operations until mid-2026.
With certification slated for 2028, this creates a “funding gap” that the company will need to address. The shift of the transition milestone to 2026 may influence investor sentiment, as the market often looks to technical achievements as validation for further capital injection.
What is the difference between the VX4 and Valo? When will Vertical Aerospace achieve full transition? What is the company’s current financial runway?
Vertical Aerospace Updates VX4 Flight Test Progress; Full Transition Targeted for Early 2026
VX4 Flight Testing Achievements
Regulatory Developments
Strategic Context and Market Position
AirPro News Analysis: The VX4 vs. Valo Distinction
AirPro News Analysis: Financial and Competitive Landscape
Frequently Asked Questions
The VX4 is the current full-scale prototype used for flight testing and validation. Valo is the recently unveiled production-intent aircraft that Vertical Aerospace plans to manufacture commercially, featuring design improvements based on VX4 data.
The company has rescheduled the full piloted transition flight, where the aircraft switches from vertical lift to wing-borne flight, for early 2026, citing weather and scheduling constraints.
As of the Q3 2025 update, Vertical Aerospace holds approximately $117 million in cash, which is projected to sustain operations until mid-2026.
Sources
Photo Credit: Vertical Aerospace