Emerging in the domain of composite manufacturing, thermoplastic polymers can enable the reduction of process times, costs, and waste. In this study, lifecycle assessment (LCA) is used to evaluate a design for a carbon fibre-reinforced thermoplastic (CFRTP) wing rib, made from carbon fibre and polyetherketoneketone (CF/PEKK). The CF/PEKK rib is compared to several hypothetical alternatives, considering autoclave and resin transfer moulding of CF/epoxy and milled aluminium alloy.

The comparison uses novel and state-of-the-art techniques. Using scenario analysis, several perspectives are considered: recyclability, mass-induced energy demand, and alternative energy carriers. The analysis of energy carriers and end-of-life processes incorporates prospective methods to explore the effects of the energy transition. Across these scenarios, it was found that, when there is a mass difference among alternatives of 2% or more, the lighter alternative will be preferred, regardless of other factors. Through sensitivity analyses, potential was found for this margin to grow to 3% under extreme conditions, and to around 5-10% when shifting the whole lifecycle into the future. When dealing with smaller mass differences, material production and manufacturing waste become distinguishers of environmental performance.

These insights are valuable when exploring novel materials and manufacturing methods for commercial aviation. The approach defined in this thesis can be extended to any other application which has a lightweighting imperative, such as automotive, shipping, rail, or wind turbines. Building on this thesis, guidance can be provided on how and where to apply novel materials across multiple product lifecycles.

Climate change and greenhouse gas emissions have been at the forefront of both public and academic debate for some years. Although the shipping industry has managed to remain relatively free of climate regulation this is changing with the IMO goals for 2050. The military sector has also escaped scrutiny on sustainability issues. But this is also changing as the Dutch Ministry of Defence expressed the ambition to reduce its carbon footprint, with the eventual goal to reduce the operational dependency on a scarce resource, and to comply with national and international regulation. The direct aim, therefore, is to reduce the fossil fuel consumption by 70%, and to comply with IMO regulations by 2050.
In this thesis the possibilities for reducing fossil fuel consumption and greenhouse gas emissions will be examined. This will be done for the seagoing large surface vessels of the Royal Netherlands Navy by using alternative fuels.
This question is answered through the execution of two case studies of vessels with different mission profiles: the Zeven Provinciën class Air Defence and Command Frigate and the Landing Platform Dock Johan de Witt. For both vessels, a design process is carried out in which more detail is progressively
added whilst down selecting the most suitable technologies.
The first step in the design process is an operational analysis. This operational analysis uses the perceived missions profiles and the RNLN maritime doctrine to make a prioritization in a set of technical properties or measures of effectiveness. In the second design step, a systematic design variation is used to estimate the effect that different energy carriers have on the main dimensions of the vessel. The parametric design tool developed for this is an adapted version of the SPEC tool developed by Marin. The model estimates the required power and the weight of different weight groups of the vessel. The final design step continues with a more detailed proposal for a power plant configuration for both case studies. With this detailed design a final assessment of the fuel consumption, exhaust gas emissions, and operational effectiveness is made.
Throughout the design phases it was established that the displacement of both vessels would increase significantly due to the lower energy density of the selected fuels. In the case of the Air Defence and Command Frigate, the high top speed and relatively high fuel and system weight lead to a larger increase in required fuel and installed power due to the increasing resistance when using anything but the most energy dense fuels. For the Landing Platform Dock, which has a more modest power requirement and a relatively low system and fuel weight, the increase in displacement is smaller. In conclusion, it can be said that the goals stipulated by the Ministry of Defence are attainable. The effect on the operational effectiveness varies between vessels but the overall fuel consumption, cost, and displacement are sure to increase significantly.

Before an aircraft enters the Terminal Manoeuvring Area (TMA) a delay may need to be introduced due to capacity limits. An Air Traffic Controller (ATCo) has the opportunity to introduce a holding procedure. When multiple aircraft need to be delayed in this form a holding stack may be formed. This holding stack is formed above the Initial Approach Fix (IAF). Current industry standard is able to achieve an accuracy within two minutes of planned Estimated Approach Time (EAT), at which the aircraft is planned to fly over the IAF and proceed to the TMA. In this research a display tool to aid Area Controllers (ACC) in realising a more accurate delivery and improving their situational awareness is designed, called the Stack Planner (SP). The SP assists controllers with choosing an optimal holding leg time for aircraft in the holding stack to adjust their IAF flyover time. The display aims to assist ATCo by showing the possible space of their control actions as well as system constraints. In an initial proof-of-concept experiment, comparing the SP display with a baseline state of the art display, promising results are found; the SP display shows a more manageable workload with increased situational awareness that scales with scenario complexity. The new display also shows the potential to move from minute accuracy to second accuracy. Future studies would need to investigate the extent to which scenario complexity plays a role in accuracy of delivery for both baseline and SP displays.