Validation of the IXV Mission Analysis and Flight Mechanics Design

The Intermediate eXperimental Vehicle (IXV) is a suborbital re-entry demonstrator that will be launched in 2014 focusing on the in-flight demonstration of a lifting body system with active control surfaces. The Mission Analysis and Flight Mechanics of such mission is an End to End process from lift-off to splashdown which must be compatible with requirements and constraints in terms of Flying Qualities, aerothermodynamics, layout restrictions and capabilities, structure, launcher performance, Guidance Navigation and Control (GNC), visibility from ground stations and GPS and safety. The results of this design are used to support the specification of the vehicle subsystems, like GNC, Thermal Protection System (TPS) and Ground System. The main products are a database of trajectories, a Centre of Gravity (CoG) box, a trimline and a ground stations visibility network. This paper presents the methodology and results of the validation phase carried out in support to the Critical Design Review (CDR). Validation is a fundamental step not only to verify the suitability of the design but also to obtain the detailed envelope of performances of the mission. Mission and Flight Mechanics validation is mainly based on the performance evaluation against environment and system uncertainties using high fidelity end-to-end models, intensive simulations (Monte Carlo) and worst case analyses. The conclusion is that a feasible Mission Scenario for the IXV Mission from Lift-off to Splashdown has been validated at CDR level, covering Trajectory, Safety, Visibility aspects and a Robust Flight Mechanics solution, which validates the proposed design approach.