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A series of shots are run in the T5 shock tunnel at California Institute of Technology to measure heating levels on a 70 blunt cone at angle of attack in an environment representative of the Mars Science Laboratory entry. Twenty shots are obtained in CO₂ over a range of enthalpies and pressures chosen to span the laminar and turbulent flow regimes. The data indicate that the lee side turbulent heating augmentation predicted by flight simulations is valid and must be accounted for during the design of the thermal protection system. Computational fluid dynamic simulations are generally in good agreement with the laminar data when employing a supercatalytic wall model, whereas turbulent simulations are in reasonable agreement when a noncatalytic wall model is used. The reasons for this discrepancy are unknown at this time. The turbulent heating augmentation is shown to be inversely related to freestream enthalpy. Changes in angle of attack between 11 and 16 are shown to have minimal impact on measured and computed heating. A transition criterion based on momentum thickness Reynolds number, analogous to that used in flight predictions, predicts onset with reasonable accuracy, although transition is observed to occur later than the current design criterion indicates.

This paper describes the Fast Air-Target Encounter Penetration (FATEPEN) model used in the design, development and evaluation of new anti-air weapon systems. FATEPEN is a set of fast running algorithms that simulate penetration of; and damage to, paced target structures by compact and noncompact warhead fragments, and long rods at speeds up to km/sec. Our paper begins with a discussion of the role of simulation in the development of weapons systems and more specifically in the design of anti-air missile warheads. The FATEPEN terminal interaction model is then described including our approach to penetration model development, illustrations of high velocity penetration characteristics addressed by the code, a listing of the models required for accurate effects simulations, and an overview of the FATEPEN computer code including sample model predictions. The paper concludes with brief descriptions of FATEPEN documentation, the current code validation database, the corresponding code prediction accuracy statistics and a summary of current FATEPEN usage in the weapons system effectiveness community., Prepared in collaboration with Applied Research Associates, Littleton, CO.