The program to create a distributed-propulsion hybrid-electric airplane based on a Daher TBM light aircraft has reached a key milestone with the completion of the preliminary design review. The EcoPulse team is comprised of aircraft manufacturers Airbus as well as Daher, as well as engines group Safran and France’s CORAC civil aviation research council. 

With the initial design review completed, the EcoPulse’s baseline configuration has been validated and frozen, paving the way for final assembly and integration to commence at Daher’s factory at Tarbes in southern France. Final assembly is scheduled for late 2021, with a first flight planned in 2022.   

Airbus will be responsible for aerodynamic optimization of the propulsion and the battery system while Safran is developing the distributed hybrid-propulsion system.

The airframe will retain the Pratt & Whitney PT6 turboprop engine in the front, but this will act as a thrust-delivering powerplant. A turbogenerator will charge batteries and power electric thrusters mounted on the leading edge of the wing, three on each side.  

The electric thrusters consist of 50 kW Safran EngineUS electric motors driving DUC Hélices propellers, and the motors include integrated electronics and air cooling. Safran has validated the technical configuration of the thrusters and the installation interfaces for all propulsion system components, the power management system, turbogenerator, and high-voltage wiring. Safran also plans to seek European Aviation Safety Agency certification of its EngineUS motor.

Airbus will conduct wind tunnel and endurance testing of the electric thruster to prepare to qualify the unit for the first flight, and this should take place in the first quarter of 2021. The wind tunnel runs will include tests of the electric engine and evaluation of the performance of the propeller and engine cooling. Airbus is also working on aerodynamic modeling of the airframe and simulation of the nacelle’s aerodynamic behavior.