The nacelle system developed by Nexcelle for COMAC's C919 jetliner has been put through its paces in ground testing - during which the joint venture's innovative O-Duct thrust reverser underwent more than 1,800 deployment cycles.

At the Peebles, Ohio facility of GE Aviation, the O-Duct was cycled a total of 1,855 times in conditions representing a full range of operational scenarios, from normal deployments to extreme situations such as simulated rejected take-offs and aborted landings. These ground tests were part of engine certification and maintenance validations for the CFM International LEAP-1C Integrated Propulsion System (IPS), which will power the twin-engine C919.

The unique one-piece composite O-Duct on Nexcelle's LEAP-1C nacelle replaces a traditional thrust reverser's two-piece D-Duct. With its kinematics, the entire O-Duct moves aftward to the reverse thrust position; and the unit is driven by an electrical thrust reverser actuation system (E-TRAS).

These features are key elements of Nexcelle's contribution to the LEAP-1C's Integrated Propulsion System design, providing benefits that include lower weight, increased efficiency and reliability, along with improved maintainability.

With the ground testing at Peebles completed, the nacelle has been disassembled and its components sent to Nexcelle's joint venture partner companies - Safran Nacelles and GE Aviation's Middle River Aircraft Systems - for detailed inspection.

"We have examined everything down to the smallest component, including hardware that was checked out at our build-to-spec. suppliers,” explained Olivier Rougelot, the C919 nacelle program manager at Safran Nacelles. “This is to confirm that the nacelle components performed as planned, and are ready for operational service."

The O-Duct concept was pioneered by Safran Nacelles, and evolved from the company's concept for a highly-efficient, advanced nacelle configuration and pylon.