The first flights of a pair of hydrogen-powered technology demonstrators are now set to happen early in 2023. As 2022 drew to a close rivals ZeroAvia and Universal Hydrogen were making final preparations to begin their respective flight tests with Dornier 228 and Dash 8-300 twin turboprop regional airliners.
On December 23, the UK Civil Aviation Authority (CAA) issued a permit to fly for ZeroAvia’s 19-seat Dornier 228, which has been involved in ground tests at Kemble Airport in England for several months. One of the aircraft’s Honeywell TPE-331 turboprop engines has been replaced with the U.S.-based start-up’s hydrogen-electric powertrain.
ZeroAvia, which has received funding from the UK’s HyFlyer II program, is aiming to have finalized the production configuration for the ZA600 propulsion system by the end of 2023. The company is aiming to have the first aircraft converted under supplemental type certificates and in commercial service during 2025. It has reported “pre-orders” for 1,500 of the 600 kW engines and has been working with airlines preparing to begin operations.
The permit from the CAA was issued under the aviation safety agency’s Part 21 rules, which are more stringent than the experimental conditions that applied to ZeroAvia’s earlier tests with a six-seat Piper Malibu aircraft that started in 2020. That aircraft crashed during a flight in April 2021, with the UK Air Accident Investigation Branch’s report identifying errors in operational procedures for inverter lockouts causing a sudden loss of power.
Universal Hydrogen Aims to Convert Larger Aircraft
Like ZeroAvia, Universal Hydrogen also aimed to start flying its technology demonstrator by the end of 2022. In mid-December, the U.S. company confirmed to FutureFlight that the first flight with a converted Dash 8 had been rescheduled for January, following taxi tests to be conducted just before the holiday season.
"Regarding timing, the integration of the hydrogen fuel cell powertrain into the flight test aircraft took somewhat longer than anticipated,” said a spokesperson for Universal Hydrogen. “Integration is now complete and the aircraft is undergoing ground testing. We aim for taxi tests before the holidays and the first flight in January. "
Universal Hydrogen’s business plan calls for it to start delivering converted 70-seat ATR72 and ATR 42 twin turboprops in 2025 under an STC issued by the FAA. It also intends to produce hydrogen-powered versions of the 50-seat Dash 8 aircraft and has reported provisional orders for both types at its facility in New Mexico.