Waiting in the wings

Future aircraft could be lighter, more energy-efficient and cheaper to maintain as a result of electromechanically controlled wing surfaces.

One of the goals of the EU-funded More Open Electrical Technologies (MOET) project is to include more electrical systems in the internal architecture of aircraft.

The research and development team from industrial partner Airbus hopes to replace the heavy, cumbersome hydraulic systems that now control the movement of ailerons, the hinged surfaces hinged at the back of the wings that deflect up or down to help aircraft bank and roll.

These surfaces are moved hydraulically, but in future the deflections could be controlled with an electrical motor and small mechanical parts.

Airbus is working with researchers from the Universitat Politécnica de Catalunya in Spain to develop a system for diagnosing the functioning of the electrical motor that moves the ailerons.

Xavier Alabart, one of the university's engineers, said the health of the motor would be determined by monitoring the current being driven from the electrical motors. The information would be processed and displayed to pilots in the cockpit.

Alabart said this monitoring is not possible with current hydraulic systems, which are predicted to have a finite lifetime and so are changed at a specific time regardless of their health. 'There is a lot of money lost there because if the hydraulic system components are OK you are replacing them when you don't have to,' he said. 'On the other hand, if you have a component that is degrading faster than you expect, you are changing it too late.' Aircraft companies need to know more than whether or not their motors are working, said Alabart. 'A diagnostic system will track all the small changes a motor goes through from being OK to having a failure.'

The electromechanically controlled ailerons would be a small part of the electrical architecture of future aircraft.

The MOET project, which includes 13 other academic teams and 46 hi-tech companies including Saab, Siemens and Rolls-Royce, aims to create an electrical design standard for aircraft that will make the European aeronautical industry more competitive.

Alabart claimed the enhanced aircraft design will also reduce emissions and improve operational capacity. 'Air traffic is going to increase a lot in the next 10 to 20 years and the EU is enforcing the entire airline industry to be more energy-efficient,' he said 'A more electrically integrated aircraft will help airlines achieve improved efficiency.'

The Universitat Politécnica de Catalunya team and Airbus are working on two large-scale prototypes of the electromechanically controlled ailerons that will be demonstrated on a grounded test aircraft in Toulouse, France, in 2010. Alabart cautioned it could be at least a decade before they are installed in commercial aircraft.

Siobhan Wagner