The design and planning of space trajectories is a challenging problem in mission analysis. In the last years global optimisation techniques have proven to be a valuable tool for automating the design process that otherwise would mostly rely on engineers’ expertise. The paper presents the optimisation approach and problem formulation proposed by the team Strathclyde++ to address the problem of the 9th edition of the Global Trajectory Optimisation Competition. While the solution approach is introduced for the design of a set of multiple debris removal missions, the solution idea can be generalised to a wider set of trajectory design problems that have a similar structure.