The Space Shuttle poses debris impact hazards to people and property during ascent, both during the initial liftoff phase of flight (Stage 1) and during the downrange overflight phase (Stage 2) where its projected debris impact footprint crosses over land areas. The assessment of the risks to the launch area from the initial liftoff debris impact hazard has been done routinely prior to Shuttle launches. However, the risks due to downrange overflight are only evaluated periodically to verify that the risk levels remain within acceptable limits. Recently a reassessment of the risks for Shuttle downrange overflight became a requirement for the returnto-flight of the Shuttle following the Columbia accident. The focus of this paper is on the methods and data used for the recalculation of the risks for downrange overflight, where the Shuttle poses hazards to Newfoundland and to areas of Europe, Asia and Africa. The Shuttle presents some interesting challenges for modeling the downrange overflight risks because of it’s various abort modes and the way the vehicle responds to various modes of failure. In order to improve the modeling of the overflight risks, NASA has generated new data; in particular new malfunction trajectories, guidance and performance dispersed trajectories, failure mode definitions, failure rates, and reentry breakup debris models. Based on this new data, new methods and algorithms to perform the downrange overflight risk calculations have been developed. This pap