The aim of this work is to present the preliminary performance studies of the unmanned, lightweight (less than 10 kg), supersonic research aircraft. The studies comprise the typical mission for the aircraft's first supersonic version, based on the aerodynamic, thrust, and mass characteristics presented in a previous work. The aircraft, named as “Pohox”, is an Unmanned Air Vehicle, or “UAV”, and is intended to be the flying test bed for a multi cycle engine capable to provide thrust in subsonic, transonic and supersonic regimes. Different tools have been developed to perform the analysis. In the analysis, different flight paths are considered in order to provide insights in terms of fuel consumption, altitude and speed gain. Aircraft ‘excess power’ diagrams have been generated, to provide guidance for the definition of the flight paths to be analyzed. Drag dependency with Mach number is considered in the analysis. In addition, two important regions in the Aircraft's altitude versus speed diagram are determined: the “feasibility flight corridor” which is the region the aircraft can perform sustained horizontal or climb flight, and the “supersonic jump region”, which is the most suitable Altitude-Speed location to cross the sound barrier. The present analysis can be considered as the natural step, after aircraft first definitions, towards the aircraft detailed design; and the results obtained provide good indications of the technical feasibility of the aircraft.