A probabilistic paradigm for spacecraft random reentry disassembly

Abstract

A new probabilistic paradigm for calculating the uncertainty in casualty area of randomly reentering debris from orbital objects is presented with exemplar calculations of casualty area associated with elements of a reentering Delta II launch vehicle second stage. Sensitivity studies using a probabilistic paradigm for simulation of spacecraft random reentry disassembly have shown the importance of including uncertainties. The sensitivity of casualty area to spacecraft orientation and consequent free-flying ballistic element orientation is extreme. The notion of inherently stochastic processes during reentry is supported by recent data on recovered debris from the Space Shuttle Columbia. Casualty area standards for spacecraft that rely on deterministic estimates may not be providing the level of safety assurance that was intended.