Nexcelle has completed a demonstration of its advanced technology nacelle, a key component in the integrated propulsion system (IPS) for the CFM Leap-1C-powered Comac C919.
The pylon and nacelle advanced configuration for high efficiency (Panache) test took place in May on outdoor test stand 3E at GE Aviation's Peebles, Ohio facility, using a CFM56-5C engine with Nexcelle components. Included was the C919's electrical thrust reverser actuation system (ETRAS) and its composite one-piece O-duct.
Nexcelle's Panache demonstrator during May tests
The ETRAS, which slides the 0-duct rearward to divert bypass air in the reverse direction, was activated more than 200 times during the test series, simulating normal landings as well as aborted takeoffs, says Nexcelle president, Huntley Myrie. Nexcelle is a nacelle development joint venture between GE and Safran, similar in structure to the CFM engine joint venture between the two companies.
An integral part of the IPS, the Nexcelle nacelle itself is projected to reduce fuel consumption by as much as 2% through advanced design, lower weight and collaborative design efforts between the airframer, engine maker and nacelle provider.
The Panache test was chiefly designed to verify the performance of the O-duct, a monolithic structure that surrounds the thrust reverser portion of engine and replaces the traditional two-piece "D" doors typically used.
Key benefits of the O-duct include eliminating the latches on the bottom of the D-doors, parts that have been a persistent maintenance issue, and smoothing the bypass air flow path through the section, increasing reverse thrust efficiency by as much as 10%.
The system completed its preliminary design review in May and is slated for critical design review by year's end, says Myrie. The first flight test of the Leap-1C with the Nexcelle nacelle installed is scheduled for mid-2014, two years ahead of the anticipated 2016 entry in the service of the C919.
Below is a video of a test run at Peebles, showing the one-piece O-duct opening during reverse thrusting.