Speaker
Description
Historically, re-entry risk assessment has followed a process which defines the calculations required to be made. Recently, the limitations of this relatively simple process, with respect to both the physical phenomena and the attempts to specifically alter the design of spacecraft to promote demise, have become evident.
Significant recent progress has been made in the understanding of spacecraft heating and break-up during re-entry though recent studies and test campaigns. This includes experimental testing of basic material properties, joint fragmentation phenomenology, and demise of complete spacecraft components. Theoretical work on aerothermodynamic heating to compound shapes has also provided further evidence that the local length scales drive much of the heating rate.
These new findings allow an improved assessment of the uncertainties in both the physics and the modelling of destructive re-entries to be performed, as well as the assessment of potential biases in the current generation of destructive re-entry tools. In particular, this provides a potential basis for the capture of relevant physics by which design-for-demise techniques could be properly verified.
Construction of a statistical tool which will allow this new knowledge to be captured, and the uncertainties to be respected, is part of a new ESA study. This study has the objective of assessing how a procedure for assessment of the casualty risk from destructive re-entry can be realised in a pragmatic way commensurate with the available research findings. To assure this, the activity will make use of the scientific experts in the field as well major system integrators. This procedure will be tested on a range of spacecraft and re-entry types, simulating the mission development phases, in order to ascertain its usefulness for risk assessment.
