Emissions of future conventional aircrafts adopting evolutionary technologies.

The current aviation sector has been shaken by COVID-19, but a few years prior, the industry was experiencing a time of prosperity never seen before. These years were marked by the introduction of new models and record sales. In particular, two cases stood out from the rest: the Boeing 737 MAX and the Airbus A320neo.

Damage Characterization of Bio and Green Polyethylene-Birch Composites under Creep and Cyclic Testing with Multivariable Acoustic Emissions.

Despite the knowledge gained in recent years regarding the use of acoustic emissions (AEs) in ecologically friendly, natural fiber-reinforced composites (including certain composites with bio-sourced matrices), there is still a knowledge gap in the understanding of the difference in damage behavior between green and biocomposites. Thus, this article investigates the behavior of two comparable green and biocomposites with tests that better reflect real-life applications, , load-unloading and creep testing, to determine the evolution of the damage process. Comparing the mechanical results with the AE, it can be concluded that the addition of a coupling agent (CA) markedly reduced the ratio of AE damage to mechanical damage.