Postflight Analysis of Inflatable Reentry and Descent Technology Blackout During Earth Reentry.

The Inflatable Reentry and Descent Technology flight performed in 2006 was not nominal. The flight was characterized by a blackout period shorter than expected. Here, we apply two methods that can be used to perform postflight analysis. The first, based on an engineering approach, has already been used for the preflight analysis. The second involves coupled calculations between a computational fluid dynamics and an electromagnetic solver. The main objective of this postflight analysis is to validate this advanced approach using flight data and to assess the validity of the engineering method. Numerical results show that the engineering method overpredicts the blackout duration due to the fact that this method is based on a severe on/off switch. The coupled approach leads to an underestimation of the blackout period. Several uncertainties, such as the influence of ablative material on ionization, could explain this discrepancy. Analysis establishes the validity of the coupled approach, but its accuracy depends strongly on the modeling used for the calculations. [ABSTRACT FROM AUTHOR]