Testing milestone advances certification readiness for integrated electric propulsion architecture

SION, SWITZERLAND — H55 has completed System Safety Function Verification Testing of its integrated Energy Storage System (ESS), marking a key step in its certification pathway and system-level validation.

SYSTEM-LEVEL VALIDATION IN INTEGRATED CONFIGURATION

The testing campaign validated the ESS in a fully integrated configuration, combining all critical subsystems into a complete operational architecture. These included battery modules, battery management units, an energy flow counter, protection and power distribution unit, and charge control unit.

The programme focused on system-level performance, communication integrity, and safety functionality under operational conditions. According to H55, results confirmed stable and predictable system behaviour, with consistent coordination across all subsystems.

SAFETY FUNCTIONS VERIFIED UNDER FAULT CONDITIONS

A central objective of the campaign was the verification of safety-critical functions at system level. This included the controlled and automatic disconnection of power under predefined fault or off-nominal conditions — a requirement for aviation certification and safe operational deployment.

The successful validation of these functions represents a step toward demonstrating system reliability within an integrated architecture rather than at component level alone.

PROGRESS TOWARD CERTIFICATION AND DEPLOYMENT

H55 stated that the milestone contributes to de-risking both its technology platform and certification roadmap. The system has been developed in alignment with certification requirements, including coordination with the European Union Aviation Safety Agency (EASA), and to aerospace-grade standards.

The company’s approach focuses on early detection, control, and mitigation of risks within the system architecture, supporting higher reliability levels required for certified electric propulsion systems.

With ongoing programmes and increasing demand for electric propulsion solutions, the completion of system-level safety verification marks a transition from validation toward deployment.

POSITIONING WITHIN ELECTRIC AVIATION DEVELOPMENT

H55’s Energy Storage System forms part of a broader effort to enable scalable electric aviation, with a focus on certifiable, repeatable platforms for aircraft manufacturers and operators.

The company traces its origins to the Solar Impulse programme and reports more than 2,000 hours of electric flight experience without battery-related incidents, supporting its certification-driven development model.