The raising concerns towards the environmental impact of the air transport sector have led the international regulation authorities to put pressure on the aeronautical industry in order to achieve ambitious goals both in the short and medium-term. The expected growth in the aviation sector for the upcoming years poses a greater challenge to both airplane manufacturers and operators who need to adopt revolutionary solutions to provide an effective response towards a more sustainable energy supply, including steep reductions in pollutant emissions and a significant improvement in recyclability. Natural materials are a viable path to address this challenge as they rely upon sustainable production processes and offer considerable advantages in terms of renewability, recyclability and biodegradability. Furthermore, evidences from recent research suggest that some natural materials offer mechanical properties equivalent or even better than conventional materials used for engineering applications in the aerospace sector. This paper presents a review of the progresses achieved in the use of natural based materials in aeronautical structures. Most of these materials are in the form of polymer based composites with either the inclusion of natural reinforcing fibres and resins or other types of natural materials used as core constituents in sandwich components, such as cork based composites. The presented data were collected from different research works and cover a broad range of loading conditions as experienced by aircraft under normal operational scenarios and taking into consideration relevant airworthiness requirements, such as fire resistance and damage tolerance. Results are very encouraging and support the use of natural based materials in aircraft structural components, opening a window of tangible opportunities for the design of more fuel efficient and environmentally sustainable aircraft in the near future
