![XA100 adaptive cycle combat engine](/sites/default/files/styles/crop_freeform/public/2022-12/ad23-propulsion_1_ge-aerospace_2.jpg?itok=FYfZycMJ)
Adaptive Advances
General Electric and the U.S. Air Force began ground tests of the XA100 adaptive cycle combat engine in May, following similar tests of the rival Pratt & Whitney XA101 in 2021. In August, the Air Force awarded GE Aerospace and Pratt & Whitney contracts for the prototype phase of the Next-Generation Adaptive Propulsion engine program for the planned Next-Generation Air Dominance sixth-generation fighter.
![T901 Improved Turbine](/sites/default/files/styles/crop_freeform/public/2022-12/ad23-propulsion_2_ge-aerospace_2.jpg?itok=HsOdcofx)
T901 To Test
General Electric and the U.S. Army completed the “first engine to test” ground runs of the T901 Improved Turbine Engine, a 3,000-shp turboshaft that is intended to reengine the Sikorsky UH-60 Black Hawk and Boeing AH-64 Apache as well as power the Army’s planned Future Armed Reconnaissance Aircraft—a program for which the Bell 360 Invictus and Sikorsky Raider X are competing.
![GE Passport turbofan](/sites/default/files/styles/crop_freeform/public/2022-12/ad23-propulsion_3_herve-gousse-airbus_2.jpg?itok=-VNoF4qj)
Airbus Tests Its Options
In February, Airbus and GE/Safran joint company CFM announced plans to flight test a GE Passport turbofan modified for direct combustion of hydrogen fuel. The tests, on a modified Airbus A380, are scheduled for 2026. In July, the airframer additionally agreed to flight test on an A380 the open-fan propulsion system being developed under the CFM RISE program. In December, Airbus revealed plans to flight test a hydrogen fuel-cell engine (pictured) on its modified A380 testbed in the same 2026-28 period.
![Tier 1 Engineering modified eR44](/sites/default/files/styles/crop_freeform/public/2022-12/ad23-propulsion_4_tier-1-engineering_2.jpg?itok=DIF7MO0D)
Electric Progress
In an eventful year for electric aviation, Eviation flew its clean-sheet, battery-powered 11-seat Alice for the first time on Sept. 27 and Ampaire flew its hybrid-electric-powered Eco Caravan, a modified Cessna Grand Caravan, on Nov. 18. Also during the year, Harbour Air Seaplanes conducted the first point-to-point test flight with its electrified eBeaver, and Tier 1 flew an electric helicopter, a modified eR44 (pictured), between airports for the first time.
![Dornier 228 hydrogen-electric propulsion demonstrator](/sites/default/files/styles/crop_freeform/public/2022-12/ad23-propulsion_5_zeroavia_2.jpg?itok=fyK1nAVn)
Hydrogen-Electric Ready To Fly
ZeroAvia completed fast taxi testing of its Dornier 228 hydrogen-electric propulsion demonstrator at Cotswold Airport in Kemble, England, at the end of September, paving the way for flight testing. One of the Do 228’s two turboprop engines has been replaced by a 600-kW gaseous-hydrogen fuel-cell powertrain. Universal Hydrogen is also close to flying a hydrogen-electric demonstrator at Moses Lake, Washington, a De Havilland Canada Dash 8-300 fitted with a 1-megawatt fuel-cell propulsion system.
![AE2100 turboprop](/sites/default/files/styles/crop_freeform/public/2022-12/AD23-PROPULSION_6_Rolls-Royce.jpg?itok=gUQZT7ti)
Rolls Runs Hydrogen
Rolls-Royce and airline partner EasyJet in November conducted test runs on an AE2100 turboprop powered by liquid hydrogen rather than conventional jet fuel. The tests, on a rig at the UK Defense Ministry’s Boscombe Down, England, facility, used green hydrogen supplied by the European Marine Energy Center and produced using renewable energy in the Orkney Islands.
![Sustainable Water-Injecting Turbofan Comprising Hybrid-Electrics (Switch) program](/sites/default/files/styles/crop_freeform/public/2022-12/AD23-PROPULSION_7_MTU-Aero-Engines.jpg?itok=hc2jWJO9)
MTU Leads Switch
A part of Europe’s Clean Aviation research program, MTU Aero Engines is leading a project aimed at combining the benefits of its water-enhanced turbofan concept with a hybrid-electric architecture. The Sustainable Water-Injecting Turbofan Comprising Hybrid-Electrics (Switch) program includes Airbus, Collins Aerospace, GKN Aerospace and Pratt & Whitney. Together they are pursuing a 25% reduction in CO2 emissions from an engine that could enter service in the mid-2030s.
![Mach 1.7 Overture airliner](/sites/default/files/styles/crop_freeform/public/2022-12/AD23-PROPULSION_8_Boom-Supersonic.jpg?itok=B7vxapQj)
Boom Goes It Alone
Boom Supersonic in December unveiled an industry team to develop and support a purpose-designed propulsion system for its Mach 1.7 Overture airliner, having failed to find an established engine supplier. The Symphony, a 35,000-lb.-thrust medium-bypass engine, will be designed by Florida Turbine Technologies. Manufacturing will be handled by GE Additive. Maintenance and support will be provided by StandardAero.
![modified De Havilland Canada Dash 8-100 flight demonstrator](/sites/default/files/styles/crop_freeform/public/2022-12/AD23-PROPULSION_9_Pratt-Whitney-Canada.jpg?itok=ucq-CsBP)
Hybrid Flight Demonstrator
Raytheon Technologies in December began ground tests of the hybrid-electric propulsion system that will power a modified De Havilland Canada Dash 8-100 flight demonstrator starting in 2024. With a total output of 2 megawatts, the integrated powertrain combines a 1-megawatt electric motor developed by Collins Aerospace with a Pratt & Whitney turbine powerplant adapted for hybrid-electric operation.
The year saw major commitments to developing technology for future decarbonized propulsion systems ranging from advanced turbine engines through electric and hybrid-electric powertrains to hydrogen fuel systems.