A Piper M Series aircraft being used by ZeroAvia as a flying testbed for its hydrogen propulsion system crashed on April 29 last year after electrical power was lost to both of its motors, according to a report by the UK’s Air Accident Investigation Branch (AAIB). The report found that an emergency procedure to clear an inverter lockout proved ineffective and that the company had failed to investigate previous loss-of-power incidents also caused by inverter lockouts that had happened three flights prior to the accident near Cranfield Airport in England.
In their summary of factors contributing to the non-fatal accident, in which the aircraft was badly damaged after a crash landing in a field, AAIB investigators said that ZeroAvia’s flight test team did not review the risk assessment of the testing following the loss of propulsion on two previous flights. “Ad hoc changes were made to the flight test plan, including the position where the electrical power source was switched, without the knowledge of the competent person,” they concluded.
In this article
