Zeroavia are using a Dornier Do-228-200 to test their new hydrogen fuel cell and electric motor. One of the Dornier engines is to be replaced with a YASA stack of electric motors for test flights. They approached FIRMA in 2021 to assist in the structural justification of the required modifications, both from a static and fatigue perspective.
Zeroavia developed a static load set and FIRMA helped to develop a preliminary fatigue spectrum. The biggest obstacle was understanding the existing Do-228 structure, as only limited informations was available. FIRMA worked with Zeroavia to recreate the wingbox structure in CAD from repair manuals, laser scanning, NDT and photographs. We then used this CAD data to create s shell FEM model which was successfully verified using strain gauge data.
Working with limited information, and utilising decades of experience in airframe structural analysis, FIRMA were able to produce structural justification documentation (both static and fatigue) to support the test flight program.
