Impact of MIL-STD-461D on aerospace equipments

On January 11, 1993, MIL-STD-461D was released superceding MIL-STD-461C. While 461C was a multipart document, each part specifying EMC requirements of a particular class of equipment (based on application/installation), 461D is a single part document. However, a requirement matrix is provided in the document to identify EMC specifications and test applicability to various classes of equipment depending upon their installation. The new standard has added to, deleted and revised tests of MIL-STD-461C. The paper discusses such changes, specifically for the equipment used in space systems including launch vehicles. An attempt is made to rationalise the changes. The three new tests, i.e., bulk cable injection tests (CS114, CS115, CS116) will certainly call for design changes in the equipment. The paper discusses the impact of these changes on aerospace equipment as well as on EMC laboratories catering for these test requirements.