The first step in the design process is to review the requirements. After the design requirements have been review for completeness and clarity, ideas are formulated on how to meet the cited requirements. Here, producibility is considered as part of the design criteria to be evaluated for cost-effectiveness and ease of manufacture versus the degree of compliance with the functional requirements. Preliminary analyses should be made to tentatively select components, configuration, materials, and processes without locking onto the design of any tentative selections. These initial selections merely provide a basis for the designer to evaluate the concept. With a number of possibilities to consider, analysis is required to choose the approach that shows the greatest promise. As a minimum, analyses should be made of the risk involved in design alternatives, function versus cost, schedule versus cost, and components versus manufacturing capability.
Producibility is an engineering function directed toward achieving a design which is compatible with the realities of the manufacturing capability of a contractor. More specifically, producibility is a measure of the relative ease of manufacturing a product. Producibility often is identified as one of the items to be covered in a design review but is not discussed as one of the major cost drivers in the transition from development to production. Several DoD directives and MIL-STDs discuss the topic of production design but provide very little direction or guidance. Producibility, as a subset of production design, is usually not a major concern during the review activity. As a result, it is not given sufficient attention to impact the design process in the early development phases.
It should be recognized that the producibility effort must be performed by a team of specialists from across the project and supporting functions. One individual cannot possibly accomplish the total producibility effort without assistance from other functional areas. Considering the number of new processes and materials that are being developed, materials specialists should be brought into the areas of manufacturing, test and evaluation, and the design process. People from the various disciplines are necessary so that detailed interaction can occur between the product designers and the personnel who have specific knowledge of the available manufacturing technologies and their relevant costs.
Very often proof of manufacturing models are not provided or required, which results in tooling and process problems not being totally resolved prior to production. As a consequence, many producibility-type issues are not discovered until production, and depending upon the severity of these problems, rate production may be severely impacted. Retooling, new equipment, considerable redesign, exotics manufacturing processes, and the like are often require - at great additional expense and time - to allow for production quantities.
The achievement of production phase objectives usually requires the use of the most efficient, shop-proven processes for material transformation. These two process descriptors, "efficient" and "shop-proven," often tend to be mutually exclusive. New processes and approaches to manufacturing, such as computer-aided manufacturing, often do not have extensive shop experience. The challenge is to maintain maximum efficiency of manufacture within the risk levels deemed acceptable for the specific project. It is important to recognize that advanced manufacturing technology generally brings certain levels of risk to a program along with the potential benefits of improved efficiency.
A contractor design policy should be established which specifically outlines the considerations to be implemented during the production design process. Management participation in design and producibility reviews is critical to its success. Collocation of design engineers, production engineers, and the producibility function greatly encourages cooperation and participation in early reviews of the design to ensure its eventual producibility at rate. Producibility must be confirmed prior to the production decision to ensure that a stable, mature design is transitioned to the factory. In addition, it is mandatory for low risk that proof of manufacturing models be required and that all processes be proofed to ensure that the design is indeed consistent with production processes and capabilities.