A Risk-Based Method for Evaluating NASA Technology for Use in the National Airspace System

The National Aeronautics and Space Administration’s (NASA) Aviation Safety Program relied on accident data to assess the safety of its technology in the National Airspace System (NAS). The approach compared accident rates before and after introducing new technology, using the decrease as a measure of improved safety. This method restricts analysis to accidents rather than incidents, which are precursors of accidents. Reliance on accident data makes NASA’s evaluation reactionary, based on changes in accident rates. This is not useful for evaluating new technology investments. A risk-based approach defines risk as the product of the conditional accident probability (given a set of related incidents) and its consequence in constant dollars. Probabilities are derived from the Aviation Safety Reporting System and National Transportation Safety Board data. These are modeled with a Poisson probability distribution. Consequences are derived from damage payments for aviation accidents reported by the Department of Transportation.