Probabilistic Trajectory Analysis of Debris Items for Crash Investigation

Air safety investigators must seek out all available sources of evidence from an aircraft crash incident in order to make informed root cause determinations. This is especially important when the incident aircraft was not equipped with flight and voice data recorders. Previous investigations have utilized trajectory analysis methods as a technique to determine where debris items may be found on the ground after an in-flight breakup. Alternatively, if the ground placement of debris items is known, then the airspeed and heading of the aircraft may be back-calculated. In this paper, a probabilistic trajectory analysis is developed to infer crash debris initial conditions at time of impact. Digital methods including computational fluid dynamics have been employed to calculate debris item aerodynamic coefficients and probabilistic sampling techniques to determine a likely range of initial angles and initial velocities. Finally, two example cases are presented to illustrate application of the technique and its utility for design making with respect to crash investigation.