Spacecraft break-up models for the atmospheric re-entry from highly eccentric and interplanetary trajectories

During the past decades space agencies, and more recent space industry and academia as well, have developed software models to evaluate the break-up and demise of spacecraft during re-entries. Due to limited observational data for validation of these models and the operational needs of the agencies, these models are focused on re-entries from nearly circular orbits or controlled re-entries. This in turn implies that their usability for atmospheric re-entry from highly eccentric orbit and interplanetary trajectories is based on extrapolation, in some cases ignoring the physical differences. This work reviews the limited available observational data on uncontrolled spacecraft re-entries with high flight path angle. It establishes a first order approximation for the predicted break-up altitude during the re-entry from given trajectory conditions postulated on an equivalence with circular re-entry cases via the aero-thermal environment along the trajectory. The equivalence is analysed by means of simulation and inter-tool comparison