Farm machinery planning, design and operation are complicated undertaking due to time and cost constraint and due to prevalence of complicated interacting and overlapping field operations involving capacity constraints and cooperating units. The classical DSS models that applied in the past to machinery planning and policy analysis as well as to performance assessment and simulation of machinery demand, and supplies are criticized by limitations in programming and the difficulty in manipulation and storing the bulky data usually encountered in machinery records. In contrast by application of a web-based decision support system (DWDSS) the user can enjoy the facility to store the data in the server. (DWDSS), is a user-friendly interactive pr...