Due to the complexity of aircraft spare part management, the aviation supply chain and ecosystem are not deemed as transparent as desired. As a result, participants face additional cost of communication and compliancy as proprietary component data is not made immediately accessible. To solve these problems, Maintenance, Repair and Overhaul (MRO) providers currently consider to use Blockchain to track and trace aircraft spare parts. Guided by Business Model Stress Test, this thesis evaluates the robustness of MRO business models when they use Blockchain as an aircraft spare part track and trace capability. Blockchain as an aircraft spare part track and capability is not only strategically relevant for cost-conscious innovating MROs, it also does not impose a risk to the robustness of their business model in most scenarios. MROs should engage in a regulatory-backed Blockchain consortium through which they share limited component data throughout the entire industry. If this is not possible, they can retreat from the consortium under the notion that their business model is threatened. Even though Blockchain could improve aviation supply chain and ecosystem transparency, the feasibility of the consortium is questionable. To remedy this concern, future research should focus on identifying strategic incentives for Original Equipment Manufacturers and aircraft operators to participate in the Blockchain consortium.