Vertical Aerospace Expands Flight-Test Fleet Ahead of Critical Design Review

The UK-based eVTOL developer, Vertical Aerospace (NYSE: EVTL) announced that its latest prototype completed its first piloted flight on June 5 at the company’s Flight Test Centre. The aircraft, introduced in December of last year, becomes the second full-scale VX4 in Vertical’s current active flight-test fleet and arrives at a pivotal point in the programme as the company prepares for Critical Design Review (CDR), a major milestone that will establish the design baseline for certification. Having a second aircraft for certification testing can help Vertical accelerate in one of the industry’s most closely watched certification efforts.

The maiden flight was conducted by Vertical test pilot Paul Stone after the aircraft received a Permit to Fly from the UK Civil Aviation Authority following a series of ground testing and validation activities.

 Paul Stone

• Test Pilot at Vertical Aerospace
• Over 200 aircraft types
• 4,800 flight hours
• Former Royal Navy Pilot (20 years)
  • Sea Harrier pilot
• Empire Test Pilot School
• Former Chief Test Pilot at Volocopter
• BAE Systems
  • Typhoon Future Capability Director
  • Director of Flight Operations
  • Chief Test Pilot for Combat Aircraft
• Former Chief Pilot for the Shuttleworth Collection
• Education:
  • Southampton University
    • BEng (Aeronautical Engineering)
  • Lancaster University
    • Distinction (MBA)

“Getting our latest prototype into flight testing is an important milestone because it allows us to learn faster in real world conditions and keep building momentum towards certification. Expanding the flight test fleet will help us validate the aircraft more quickly, reduce risk, and move more efficiently towards bringing Valo into service.” – Stuart Simpson, CEO of Vertical Aerospace

• Headquartered in Bristol, England 🇬🇧
• NYSE: EVTL
• Established in 2016
• Founded by Stephen Fitzpatrick (Founder of Ovo Energy and former owner of F1 Manor Racing team)
• CEO: Stuart Simpson
• Former Chairman: Dómhnal Slattery
• Manufacturer of Valo all-electric eVTOL
• Plans for future hybrid-electric powered eVTOL capable of 1,000 mile range

While first flights are often viewed as symbolic milestones, the significance of this aircraft lies in what comes next. With two aircraft now flying, Vertical can conduct multiple test activities in parallel, increasing the pace at which certification-relevant data can be gathered.

The company’s original VX4 prototype continues to perform transition-flight testing after successfully completing multiple piloted transitions between vertical and wingborne flight. Meanwhile, the newly introduced second aircraft will progress through the same flight-test envelope, including thrustborne hover operations, conventional wingborne flight and transition testing.

VX4 Full-Scale Certification Test Fleet

• G-EVTA (First VX4 certification-representative prototype)
  • First VX4 built to certification-representative configuration
  • Completed piloted transition-flight testing across full flight envelope
  • Achieved historic full two-way piloted transition flight (vertical ↔ wingborne in a single mission, 14th of April 2026
  • Continues supporting flight-test and systems validation activities alongside second prototype
• G-EVTB (Second VX4 certification-representative prototype)
  • Latest VX4 aircraft to join the flight-test programme
  • Completed maiden piloted flight on 5th of June 2026
  • Will progress through thrustborne, wingborne, and transition-flight testing to expand certification dataset

Back in December, Vertical CEO Stuart Simpson, explained the significance of having another full-scale VX4 prototype for testing:

“As we look ahead to 2026, the addition of our final prototype marks an important step in closing out our prototype flight test programme and maintaining momentum towards commercialization. Our test pilots are eager to get this aircraft into the air.” – Stuart Simpson, CEO of Vertical Aerospace

For aircraft developers pursuing certification, additional flight-test capacity can have a meaningful impact on programme timelines. As test campaigns become increasingly complex, the ability to dedicate separate aircraft to different objectives helps reduce bottlenecks and allows engineering teams to validate systems, software and flight characteristics more efficiently.

The latest flight also marks the final prototype expected to join Vertical’s fleet before completion of Critical Design Review. In traditional aerospace development programmes, CDR represents one of the most important engineering milestones, confirming that an aircraft’s design is sufficiently mature to support certification and production planning.

Following CDR, Vertical intends to begin preparations for assembly of its first pre-production aircraft, moving the programme into its next phase of development.

The milestone comes as the broader eVTOL sector enters a more demanding stage of maturity. After years focused on concept development and prototype demonstrations, leading manufacturers are now being judged primarily on their ability to achieve regulatory certification and scale manufacturing.

Vertical’s strategy differs from some competitors by relying on full-scale piloted aircraft that closely resemble the intended production configuration. The company says its prototypes share the architecture, systems and flight characteristics planned for the commercial version of its Valo aircraft, enabling certification-focused testing earlier in the programme.

Valo

• 100 mile range
• 150 mph top speed
• Up to 6 passengers
• Airliner-level safety certification in 2028
  • Airliner-level safety standards (UK/EU 10-⁹; CAA/EASA, SC-VTOL Category Enhanced)
• Quiet performance (<50 dBA in cruise)
• Room for six cabin bags and six checked bags
• 550 kg / 1,200 lbs total payload

Planned Hybrid Retrofit for Second VX4 Prototype

Beyond supporting certification efforts, the new aircraft is also expected to play a role in public flight demonstrations during the coming year. Once testing in its all-electric configuration is complete, Vertical plans to retrofit this second aircraft for hybrid-electric flight testing.

The decision reflects a growing industry interest in hybrid-electric propulsion as developers seek to expand mission capabilities beyond urban air mobility. While battery-powered all-electric aircraft remain the primary focus for short-range passenger transport, hybrid-electric systems could offer greater range, endurance and payload capacity for applications such as defence, logistics and regional transportation.

Vertical’s hybrid-electric ambitions place it among a growing number of companies exploring how advanced air mobility technologies might serve markets beyond traditional air taxi operations.

The company continues to market its Valo aircraft as a piloted, four-passenger eVTOL designed to deliver zero-emission flights while maintaining the safety standards expected of commercial aviation. Vertical says it has secured approximately 1,500 pre-orders from customers including American Airlines, Avolon, Bristow, GOL and Japan Airlines.

With a second aircraft now airborne and Critical Design Review approaching, Vertical enters the second half of 2026 with increasing momentum. The next major challenge will be converting that momentum into certification progress as the drive to bring commercial eVTOL aircraft into service moves into a new phase.

More Info:

Vertical Aerospace (official website): click here

Vertical Aerospace’s Final Full-Scale Prototype Completes First Piloted Flight (9th of June, 2026): click here

Vertical Aerospace Doubles Flight Test Capacity With Final Prototype (22nd of December, 2025): click here