Pitch Change Mechanism Conceptual and Preliminary Design Activities. A principal contributor to affordable and sustainable public air transportation will be the introduction of more fuel-efficient propulsion systems, one of which is the Open Rotor Engine concept. Unlike turbofans, open rotors must vary blade pitch to accommodate power and aircraft speed range, so a key element to the viability of the concept is the actuation and control of the blade pitch via the Pitch Change Mechanism (PCM).

GE Aviation Systems Ltd (trading as Dowty Propellers) is engaged in specifying requirements and concept evaluation for PCMs for direct-drive pusher open rotors in the EU 7th Framework DREAM SP3 work package 3.1. Dowty Propellers has also participated in similar studies with GE Aviation Engine division to assess the viability of a number of PCM control and actuation concepts. GE Aviation proposed to build on this background to support the SAGE 2 engine PCM. The work packages proposed via this application will focused on developing the critical technologies associated with the selected actuation system concept. The proposal describes the activity supporting functional, architectural, failure mode, mass, and performance analyses, the creation of a preliminary bill of material and definition of system performance and safety verification.

The deliverables from the programme were the definition of the preferred PCM concept with 3D geometry, performance, functional, safety and reliability assessments, interface definition and power plant control system integration architecture proposal. The work packages were closely aligned to the engine demonstrator requirements, in preparation for the launch of demonstration hardware.