Case Study

New engines offer ever-lower fuel burn and emissions

Environmental Technology

While aircraft efficiency has increased by well over 70% since the first jets, recent research has created new concepts that will continue delivering improved fuel-efficiency in the coming years.

CFM International, a consortium of GE Aviation and SNECMA, is developing its LEAP-1A/B/C advanced high-bypass turbofan engine for entry into service in 2016. The new engine will incorporate new aerodynamic designs, materials, coatings, combustion and cooling technology, and improved integration between the engine and airframe. These engines will cut fuel consumption, lower emissions of NOx and reduce the noise footprints 75%.

Pratt & Whitney’s Pure Power ‘geared turbofan’ is also due to enter service. In this new design a gear system allows the engine’s fan section to operate at a slow speed while hotter sections of the engine – the low-pressure compressor and turbine – simultaneously operate at much higher speeds. This increases engine efficiency, lowers fuel consumption, CO2 emissions and noise. It will offer around a 15-20% fuel economy improvement over existing engines. It is due to enter service in 2013.

Rolls-Royce’s latest Trent engine is currently under final testing for entry into service in 2014. The Trent XWB shows a 16% increase in fuel efficiency since the first Trent, which entered service in 1996. The new engine uses more advanced aerodynamics and materials as well as next generation clearance control, intelligent management of internal air systems, enabling next-generation bypass ratios and pressure ratios..

Around 2025, a new generation of ‘open-rotor’ engines will enter the market. These are gas turbines driving two high-speed propellers moving in opposite directions.  GE Aviation, Rolls-Royce and SNECMA are developing new aerodynamic and material technologies which could result in the return of propeller-driven engine on larger aircraft, but with higher flight speeds and lower noise levels. Wind-tunnel tests on prototype models have shown that, thanks to new propeller designs, these engines could offer a 25% to 30% fuel improvement over current production engines, while meeting advancing noise standards.