Pioneer Venus probe targeting maneuver design

The Pioneer Venus probe targeting maneuver sequence, both as planned and as executed, and the design and reconstruction procedures are reported. The targeting objectives, the spin-stabilized multiprobe spacecraft (Bus), probe entry conditions, and maneuver modes are examined. Planned probe targeting sequence and predicted Bus entry dispersions are detailed, and the new software used because of the unique mission requirements is described. Design rules for the probe targeting maneuver, actual probe targeting event times, and the Bus trim maneuver are considered, and it is concluded that this mission demonstrated that the maneuvers that were executed were more precise because of inflight maneuver reconstruction, and that the a priori estimates provided to the orbit determination processing allowed an accurate orbit solution earlier than would have otherwise been possible.