At one end of the spectrum are COTS assemblies whose design, internal parts ² , materials, configuration control, and qualification methods are at least partially controlled, or influenced, by aerospace customers (either individually or collectively). An example at this end of the spectrum is a VME circuit card assembly. While the design, internal parts, materials, configuration control, and qualification methods are controlled by the assembly suppliers, the assemblies are targeted for ADHP applications, and thus the manufacturers expend considerable effort to understand their customers’ needs; and they design, produce, and qualify their products accordingly. VME assembly suppliers are sensitive to feedback from their customers, and are willing to make changes in response to that feedback. The response is only general, however, and it is not likely that a specific change will be made unless the supplier determines it to be beneficial to the product’s market performance.

At the other end of the spectrum are COTS assemblies whose design, internal parts, materials, configuration control, and qualification methods are not controlled, or controllable, in any way by ADHP customers (either individually or collectively). An example is a disk drive targeted for an industry other than aerospace. Aerospace customers are not likely to obtain any information beyond the published data sheet; furthermore, the data sheet, and other important information, may be changed without notice. Typically, it is not possible for aerospace customers to purchase these assemblies to a specific issue of a data sheet.