The Power Optimised Aircraft (POA) project is a technology platform within the European Community (EC) 5th Framework Programme. It is a four-year project with a budget of about 100 million Euros, jointly funded by the EC and the consortium, which is being coordinated by Liebherr-Aerospace. The aim of POA is to identify, optimise and validate innovative aircraft equipment which contributes to the reduction in consumption of non-propulsive power.
The right figure shows a diagram of the conventional power generation, distribution and use on a civil aircraft. Fuel is being converted into power by the engines of the aircraft. Most of this power is expended as thrust in order to move the aircraft. The remainder is converted into four forms of non-propulsive power known as mechanics, pneumatics, hydraulics and electrics, which are necessary to operate the aircraft systems. To mention a couple of the systems on-board an aircraft studied in POA, these are: environmental control, electric power generation and distribution, primary and secondary flight controls, landing gears and brakes, commercial loads (galleys, lighting, in-flight entertainment).
In the POA project, a contemporary large civil aircraft is defined as the reference. A set of so called “feasible architectures” is considered with the introduction of novel technology equipment, and several feasible architectures were defined having different levels of technological maturity. Within POA, the main focus is on several more- and full-electrical aircraft architectures having engine embedded starter/generators, reduced bleed or bleedless environmental control, reduced hydraulic or fully electrical flight control and landing gear actuation. These technologies are expected to be mature for an entry into service by the year 2010. All changes in non-propulsive power demand, weight, reliability, cost etc. involved with novel on-board systems and equipment are assessed in POA with regard to the reference aircraft.
Within the POA consortium, the aircraft manufacturer defines the top-level system requirements, the reference architecture and, together with the engine and equipment manufacturers, the feasible aircraft architectures which meet the top level systems requirements. The figure to the right shows an example of such a feasible aircraft architecture.
Every architecture is defined at aircraft level, which means that it comprises all systems and equipment to be installed in an aircraft. The central definition of the feasible architectures is the basis for the work of the engine and equipment manufacturers in developing novel equipment. The Institute has employed the definition of the reference and feasible architectures for developing the VIB model library.