About H55 

As the technological spin-off of Solar Impulse, the first electric airplane to fly around the world, the mission of H55, is to make aviation clean, safe, and affordable.

The company’s strengths and competencies lie in developing propulsion and energy storage solutions which are modular, lightweight, and certifiable.

Having integrated and flown 4 electric airplanes, the Swiss start-up has been selected by Pratt & Whitney Canada to provide the battery pack for its regional hybrid-electric flight demonstrator. This recent announcement is a further illustration of H55’s position as a major enabler in the electric commuter market.

Your Role

As a Senior Electrical Hardware Engineer (Consultant), you will take a technical leadership role in the development, verification, and documentation of Electronic Control Board Assemblies (ECBA) for our Energy Storage System (ESS). You will operate under EASA Part-21J regulations, contributing to certification deliverables with a strong focus on compliance to standards such as:

• SAE ARP4754A – System Development Lifecycle
• SAE ARP4761 – Safety Assessment for Aircraft Systems
• RTCA/DO-254 – Design Assurance for Airborne Electronic Hardware
• RTCA/DO-160 – Environmental Testing
• AMC 20-152, RTCA/DO-178, DO-331 – As applicable for systems interaction and V&V alignment
• ASTM F3230 – Electronic Parts Qualification

Key Responsibilities

Design Ownership & Technical Leadership

• Define and review Board-Level Requirements with full traceability to system functions and safety objectives
• Guide the development of mixed-signal circuits including power supplies, protections, sensing, and control interfaces
• Support or lead preliminary and critical design reviews (PDR/CDR)

Documentation & Compliance

• Produce and review technical documentation including:

  • Design Descriptions, Functional Block Diagrams, and Interface Control Documents (ICDs)
  • Design Analysis Reports (e.g., Worst Case Analysis, Error Budget, Timing, Power Dissipation)
  • Verification & Validation Plans (VTP, VTPR) aligned with ARP4754A / DO-254
• Perform peer reviews and sign-off on engineering documents as per DOA procedures
• Ensure all development data complies with DO-254, internal configuration control, and certification audit expectations
• Contribute to safety documentation such as Failure Modes and Effects Analysis (FMEA) and Hardware Development Plans

Verification, Test & Certification Support

• Define and support Verification Test Procedures (VTP), Qualification Test Procedures (QTP), and ATP (Acceptance Test Procedures)
• Ensure compliance with DO-160 environmental testing including vibration, temperature, EMI/EMC
• Participate in SOI audits and interface with certification authorities on behalf of the hardware function
• ​​​​​​​Support integration and troubleshooting of boards during system testing and environmental qualification

Team Contribution & Mentorship

• Provide technical mentorship to hardware team members and promote a culture of excellence in documentation and analysis
• Review the team’s schematics, PCB layouts, and test reports
• Support the development and maintenance of checklists, guidelines, and standards used throughout the ECBA lifecycle
• ​​​​​​​Promote best practices aligned with ARP4754A and model-based/system engineering principles (DO-331)

Your Profile

Education & Experience

• Bachelor’s or Master’s degree in Electronics, Electrical Engineering, or a related discipline
• Minimum 7–10 years of experience in high-reliability electronic hardware development (aerospace, automotive, industrial, or medical)
• Strong experience with DO-254-based development lifecycles, ideally in certified programs

Technical Expertise

• Deep knowledge of analog/digital hardware design, including filtering, protection, power supply design (DC/DC), and measurement systems
• Proficient in circuit analysis, simulation (SPICE or Simetrix), and EMI/EMC mitigation
• Skilled in ECAD tools (Altium Designer preferred) for schematic capture and PCB layout
• Fluent in reading and producing engineering documentation, specifications, and test procedures
• ​​​​​​​Experience working with aerospace qualification and development standards:
  • SAE ARP4754A, ARP4761, DO-254, DO-160, AMC 20-152, ASTM F3230
  • Awareness of DO-178, DO-331 for multidisciplinary integration

Soft Skills & Consulting Mindset

• Strong analytical thinking, with a structured and rigorous approach to engineering problem-solving
• Excellent communication and documentation skills, with an ability to present clearly to internal and external stakeholders
• Demonstrated ability to work independently and act as a technical authority
• ​​​​​​​Fluent in English (oral and written); French is an advantage

Why Join H55 (as a Consultant)?

• Work on cutting-edge energy storage technologies at the core of tomorrow’s aircraft
• Bring your aerospace experience to a mission-driven, fast-paced environment
• Collaborate within a culture built on TRUST, TEAMWORK, COURAGE, and PERSEVERANCE
• ​​​​​​​Help shape the certification and engineering excellence of next-gen clean aviation systems

What we offer 

• An amazing work Location in Sion, Valais in the heart of Swiss Alps.
• A highly dynamic and multicultural environment where you can grow and learn by working on ambitious challenges to shape the future of Electric Aviation.

We hope this role sounds exciting and could be your next step, if so follow the steps to apply, we are looking forward to receiving your application.

H55 is an equal opportunity employer and welcomes applications from all qualified individuals regardless of race, sex, disability, religion/belief, sexual orientation or age. All aspects of employment including the decision to hire, promote, discipline, or discharge, will be based on competence, performance, and business needs.