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Debris Risk Assessment (DebRA) is an APT developed model for flight safety analysts that assesses the risks of RLV (Reusable Launch Vehicle) failure modes. DebRA first determines the hazard area from user input about nominal trajectory and failure mode information. DebRA then compares that hazard area with a population database to quantify the risks to the surrounding population. DebRA models major RLV failure modes from Malfunction Turns (trimmed or tumbling), Explosions / Breakups from any origin (onboard fuel explosion, dynamic loading, or destruct), to Engine Shutdown failures. For each time increment of each selected failure mode, DebRA generates a hazard footprint by propagating the debris to impact. The expected fatalities are computed separately for each failure mode in a risk table, which allows the analyst to quickly identify those failure modes which drive the overall mission risk.

DebRA Graphical Output Example

The following plot depicts a vehicle flight into a target area. The ellipses represent potential debris from various failure modes of that vehicle. The speed of this demonstration is faster than the real-time occurrence it simulates.

DebRA Example

Point of Contact

Bob Baker 256.327.3373