SINGAPORE—Following the recent completion of hybrid-electric tests of a modified Passport engine in the U.S., GE Aerospace is displaying a large-scale model of a CFM Open Fan configured with a notional hybrid power system at the Singapore Airshow.

The Open Fan model shows representative electrical power connections running from and to the high pressure (HP) and low-pressure (LP) shafts. 

The concept, which is being explored under the joint GE-Safran CFM International’s Revolutionary Innovation for Sustainable Engines (RISE) technology initiative, is being evaluated for potential incorporation for additional efficiency gains in the Open Fan.

Tests of the hybrid-electric system on the Passport were conducted at GE’s facility in Peebles, Ohio, and formed part of the Turbofan Engine Power Extraction (PEx) program under NASA’s Hybrid Thermally Efficient Core (HyTEC) initiative. The tests gave GE its first chance for measuring power transfer, extraction and injection, using a full-scale engine and will feed into RISE.

The work at GE evaluated the impact of electric power on engine operating parameters like temperatures and speed, as well as how hybridization affects steady-state and transient operating cycles. Both spools were also powered purely electrically during the program to evaluate a zero- or low-emission mode in which future hybrid aircraft would use battery or APU-provided electrical power solely for taxiing.

Hybrid elements involved in the tests include motor-generators on the HP and LP spools along with offboard motor controllers. Testing included runs of the Passport in full hybrid mode, which involved adding externally generated power into the engine.