Leonardo I4N Innovation for Nacelles project engine nacelles
@ Leonardo

With the I4N – Innovation for Nacelles research project, Leonardo drives technological advances for aero engine nacelles

As a technology leader and global player in aerospace, defence, and security, Leonardo has extensive experience in manufacturing engine nacelles (the engine casing that incorporates systems and technologies essential for safety and flight comfort) for leading commercial aircraft such as the giant Airbus A380, the Embraer ERJ 170-175 passenger transport jet,  the COMAC ARJ21 regional transport jet, or the Dassault Falcon business jets.

Leonardo is one of the few global players able to integrate the complete engine nacelle system. Following the results of aeroacoustic tests performed at the AneCom AeroTest Facility in Wildau (Germany), one of the world’s most advanced engine test facilities, Leonardo has become the first aeronautical company to design, build, and test in a representative environment, innovative full-scale acoustic liner panels that can absorb engine noise efficiently over a wide range of frequencies.

With these tests, Leonardo is also the first company to reach Technological Readiness Level (TRL) 6 with such novel designs. The TRL scale is a technological classification first adopted by NASA, with TRL6 representing the highest technological readiness level before flight.

The ‘Innovation for Nacelles’ (I4N) Research and Development programme, launched by Leonardo in 2019, allowed it to achieve this ground-breaking advance and also to investigate other solutions for nacelle applications, such as a resistive composite material for nacelle anti-icing, along with an innovative sensor to detect ice, raising the technological maturity of nacelle development to an even more advanced level.

I4N benefited from a contribution from the ‘Innovation Agreement’ signed with MIMIT (formerly MiSE) and the Lombardy Region because it aimed to develop technologies to support the coming social and environmental challenges of air transport.

There are four streams of research in nacelle technology:

  • Noise reduction: development of new technologies based on new materials, new design concepts, improved prediction models, and advanced production technologies. AneCom tests have showed the ability to reduce inlet noise levels (cumulative over the three aircraft noise certification conditions) up to 7.3 dB EPNL (Effective Perceived Noise Level) compared to state-of-the-art solutions on today’s aircraft. In the acoustic panels with an innovative core, a cavity pattern with a complex geometry replaces the traditional honeycomb core used in current nacelles. This improves the sound-absorbing performance compared to conventional panels over a wide frequency band. Leonardo has filed two patents for these technologies and has already launched the second phase of industrialization.
  • Reduced energy consumption: development of new architectures and solutions for the design of engine air inlets and a low-energy electrical system for ice protection.
  • Thrust reversers (used on landing to decrease the aircraft stopping distance): developing new eco-friendly concepts and solutions that integrate innovative materials (such as nano-loaded composites) for exceptional fire resistance while ensuring structural capability.
  • ’Digital twin’ design and manufacturing solutions based on composite materials and robotic manufacturing technologies.

Through the I4N research project, Leonardo has defined and is implementing a technological road map that will allow the company to produce beyond state-of-the-art engine nacelles for all types of passenger transport aircraft.