Europe’s Clean Sky R&D Advances Regional Aircraft

By Graham Warwick
Source: Aviation Week & Space Technology
May 06, 2013
Credit: Clean Sky

Regional airlines may have shed their humble origins as commuter carriers, but regional aircraft are still best known for their simplicity and economy, rather than their technology. But that must change if the sector is to make its contribution to the aviation industry's commitment to reduce its environmental impact.

The important reductions in fuel burn and greenhouse-gas emissions now possible with the latest long-haul airliners such as Boeing's 787, and promised for next-generation single-aisle aircraft such as Airbus's A320NEO, are harder to achieve with smaller regional types making many short hops a day.

Significant improvements in efficiency and reductions in emissions on short flights require new technology but, over the decades, there has been little research directed specifically at the regional sector. The airlines' demand for low equipment prices has made it hard to get a return on such investments.

But that is changing with the inclusion of regional aircraft under Europe's Clean Sky research program. Launched in 2008, Clean Sky is a seven-year, €1.6 billion ($2.1 billion) technology initiative funded equally by the European Commission and industry with the goal of developing technology for cleaner and quieter aircraft.

The result could be a new 90-seat regional turboprop with composite airframe, laminar-flow wing, low-noise landing gear and all-electric systems, or a new 130-seat small airliner with similar technologies and either geared-turbofan or open-rotor propulsion.

Clean Sky's Green Regional Aircraft (GRA) technology demonstration is lead by Alenia Aeronautica, a partner in the ATR aircraft consortium.

The GRA project's objectives are to mature new technologies in five domains: low-drag, low-noise aerodynamics; lightweight materials and structures; all-electric systems; avionics architectures and trajectory management; and new aircraft configuration. These technologies are to be raised to a readiness level of 5 or 6 through ground demonstrations, wind-tunnel and flight tests.

Combined with new powerplants developed under Clean Sky's Sustainable and Green Engines project, these technologies have been shown in simulations to enable advanced regional aircraft configurations to meet the Clean Sky target of reducing carbon-dioxide emissions by 10-20% and noise by 10 db relative to 2000 technologies, says Andrzej Podsadowski, GRA project officer.