Vertical Aerospace VX4 Successfully Completes Phase 1 Flight Testing

The Vertical Aerospace VX4 eVTOL aircraft has completed Phase 1 flight testing, involving multiple piloted tethered flights and ground runs.

Vertical Aerospace (Vertical) [NYSE: EVTL] has passed a further flight testing waypoint in its quest for zero-emissions aviation. The company’s latest VX4 eVTOL prototype has successfully completed the first phase of piloted flight tests at the Vertical Flight Test Centre.

The Phase 1 testing involved multiple piloted tethered flights and ground runs. Over 20 piloted test sorties, the team completed 70 individual test points.

These tests simulated various flight and operational scenarios to validate the prototype’s safety in real-world conditions, including situations beyond normal operating parameters. By pushing the aircraft to its limits, Vertical demonstrated the robustness of its design.

Phase 1 Testing Complete

A crucial test involved simulating the failure of one Electric Propulsion Unit (EPU) during piloted tethered flight. This inoperative testing ensured the aircraft could respond correctly and maintain safety while airborne.

Throughout these tests, Vertical’s engineers collected and analyzed 35,000 flight and system parameters. This data verified that all systems functioned correctly and safely under different conditions, paving the way for expanded flight testing.

Alongside Phase 1, the team conducted advanced low and high-speed taxi tests. These included deliberately failing EPUs at high taxi speeds to confirm controllability and safety. These ground tests verified handling characteristics and aerodynamic performance at increasing speeds in a controlled environment.

Vertical is now collaborating with the UK Civil Aviation Authority (CAA) to expand its Permit to Fly. This will allow the company to move into Phase 2, which will include piloted thrustborne flight tests.

To accelerate the VX4’s flight test program and demonstration capability, Vertical is developing an identical full-scale prototype. Learnings from both prototypes will inform the design and development of the certified VX4 model.

Vertical Aerospace CEO Comments

Stuart Simpson, CEO of Vertical Aerospace, commented: “We progressed from our first ground test to our chief test pilot flying the VX4 in just one week. We’ve maintained impressive momentum since then.”

“We’re continually proving the safety and performance of our design, which we believe leads the market. Completing this first testing phase is a significant achievement for any eVTOL company. It showcases the strength of our aircraft, team, and partners as we advance through our flight test program towards our goal of revolutionizing travel.”

Phase 1 Flight Test Highlights

Phase 1 testing included:

Piloted tethered flight: Using closed-loop flight control for stability and safety. This included simulated failure testing to validate aircraft response when one EPU fails.
Ground vibration testing (GVT): Collaborating with ATA Engineering specialists, the team used eight heavy-duty shakers and 350 accelerometers to stress-test the aircraft in various flight scenarios.
Powertrain testing: Evaluating all components that generate and deliver power to the propellers, including High Voltage (HV) ripple tests to analyze voltage fluctuations.
Dynamic testing: Verifying correct system function before real-world flight conditions, including power-up checks and component installation verification.
Propeller testing: Balancing and spinning tests to minimize vibrations for smooth, stable flying.
Taxi testing: Low and high-speed ground tests to evaluate forward and backward movement, brake performance, and directional control using differential thrust.

This next-generation VX4 is more powerful than the previous full-scale prototype, with an impressive 20% increase in the power to weight ratio. This enables the aircraft to reach speeds of up to 150mph – the certification aircraft’s intended cruise speed.