Mach 10 Stage Separation Analysis for the X43-A

This paper describes the pre-flight stage separation analysis that was conducted in sup- port of the final flight of the X-43A. In that flight, which occurred less than eight months af- ter the successful Mach 7 flight, the X-43A Research Vehicle attained a peak speed of Mach 9.6. Details are provided on how the lessons learned from the Mach 7 flight affected separa- tion modeling and how adjustments were made to account for the increased flight Mach number. Also, the procedure for defining the feedback loop closure and feed-forward pa- rameters employed in the separation control logic are described, and their effect on separa- tion performance is explained. In addition, the range and nominal values of these parame- ters, which were included in the Mission Data Load, are presented. Once updates were made, the nominal pre-flight trajectory and Monte Carlo statistical results were determined and stress tests were performed to ensure system robustness. During flight the vehicle per- formed within the uncertainty bounds predicted in the pre-flight analysis and ultimately set the world record for airbreathing powered flight.