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30 PCB007 MAGAZINE I AUGUST 2018 Obviously, the Department of Defense is very interested in reliability. The DoD has been designing and using weapon systems since be- fore the B-52 bomber became operational 63 years ago. Reliability must be a prime consid- eration in defense design and manufacture. But just how does reliability get specified and designed into defense systems? Contrary to public belief, the DoD has no central engi- neering department watching reliability—just handbooks and/or guidelines for the various programs, prime contractors, and engineers. Central to DoD is the Defense Standards Pro- gram Office (DSPO). However, authority for system reliability does not rest with the DSPO; authority rests with the weapons program of- fices. A program executive officer (PEO) may be responsible for a specific program (e.g., the Joint Strike Fighter), or for an entire portfolio of similar programs. However, one metric of reliability within the DoD is obtained from using Handbook MIL 217—Reliability Prediction of Electronic Equip- ment, Revision F, note 2. That document dates originally to 1962 and was revised about ev- ery five years until 1995. Handbook MIL 217 contains 17 chapters on various IC/discrete components, and Chapter 16 concerns "inter- connection devices." Section 16.1 deals with through-hole mounting (remember that?) and section 16.2 for boards using surface mount devices. Various complicated Handbook 217 formulas give failures per million operating hours or in- verting to one-over failures gives "mean time between failures – MBTF." Reliability Thoughts at the Department of Defense Guest Columnist Feature Column by Dennis Fritz, FRITZ CONSULTING