(239c) From Cradle to Grave: A Comprehensive Study of the Carbon Emissions of Aircraft Cabin Interiors through Life Cycle Assessment

A large amount of polymers and plastic composite are used in the manufacturing and production of nowadays modern aircrafts in an effort to achieve the desired light weighting airframe whilst sustaining robust performance. Plastics present an attractive option for airframe construction due to their exceptional properties, notably their high resistance to corrosion and fatigue. This resistance to corrosion is especially advantageous in harsh environmental conditions, making plastics an optimal choice for aircraft that are required to operate in such conditions. Moreover, the ability to engineer plastics with good fatigue resistance enables them to withstand repeated loading cycles without the risk of crack propagation or failure. Therefore, utilising plastics alternative in building the aircraft frames and interiors presents a practical solution for reducing fuel consumption and decreasing production costs when compared to traditional metal-based airframe. Unfortunately, due to wide range of plastic materials used in airframe construction, this renders their segregation and recycling problematic once the aircraft reaches the end of its useful life and is no longer deemed safe or financially viable to continue operating. As a consequence, this create a heterogeneous mixture of plastic waste where landfill disposal and energy recovery have become a prevalent waste management practices for these plastic materials due to the difficulties associated with accurately identifying and segregating the specific types of plastics. The intricate composition of these plastic amalgams presents significant hurdles for the attainment of sustainable exit for these polymers and further, the realization of a circular economy.

Therefore, in this study, assorted plastic parts from the cabin interior of an aircraft fuselage including passenger safety unit, window panes, in-flight entertainment cover and etc. were meticulously characterised according to dimensions, colour, weight and polymer composition using Fourier-Transform Infrared Spectroscopy (FTIR). FTIR results identified polyetherimide, polycarbonate, nylon, polyvinylchloride, silicon rubber, polymethyl-methacrylate and polysulfone among other types of plastics. This finding served as the primary data in a life cycle assessment (LCA) inventory analysis where LCA was carried out to assess the environmental burden and sustainability performance of the plastics used in the aircraft cabin interior from cradle to grave using SimaPro 9.4.0.2 software. Secondary data is supported by Ecoinvent 3 database and literature. This LCA was conducted in accordance to ISO standard 14040 and ISO 14044, where the goal and scope of the study (i.e., system boundary, functional unit, impact categories, assessment method, data quality and etc.) were properly defined. Our preliminary finding postulated a hypothesis where the carbon footprint of the embodied carbon of plastics are considerably greater than the greenhouse gas (GHG) emission of fuel consumption. The discovery enabled us to identify the environmental hotspots and cost-benefit trade-offs of material selection in the pursuit of creating an environmentally sustainable airframe.