The vehicle mission simulation program predicts vehicle and implement forces and presents a complete description of vehicle trajectory for a given mission (job cycle). Productivity and cost accounting is performed and summarized at the conclusion of the mission. The purpose of the program is to enable objective evaluation of engineering alternatives in designing agricultural tractors which work with attached implements. The vehicle operates on any given terrain defined in its work cycle. The user specifies the mission path by segments having constant conditions. Performance and cost factors are calculated for each user-selected time increment and summed over the total cycle to determine productivity and unit cost.