This variance was outside the 3-sigma worst case, as estimated by the Pegasus program office. True Anomaly unconstrained 200.0 deg. Of Perigee unconstrained 241.9 deg. Longitude of Node 307.675 deg. Anomaly Response Unreliable GPS data used to update ACS propagator resulting in loss of attitude knowledge.
Spacecraft enters safe-mode aborting further burns.
Assist GPS and ACS subsystem engineers to generate state vectors following each burn. Replan groupings of burns to allow additional ground station contact and minimize possibility of ACS-induced aborts. Perform quick check real-time GPS state vector and confirm each burn execution. Alter predictive model to accommodate. Target slightly greater performance than required to achieve desired results.