The engineer designs, develops, implements, verifies and tests algorithms that perform guidance, navigation and control of aircraft, spacecraft, launch vehicles and upper stages during powered and coast phases of flight, earth orbit, interplanetary cruise and orbital insertion, as well as during staging events. Inertial Tracking: extended and unscented Kalman filtering, non-linear state estimation, inertial attitude and line-of-sight estimation, multi-hypothesis tracking, multi-sensor fusion, multi-hypothesis tracking, Bayesian inference, angle-only tracking, feature-aided tracking, image tracking.