Required to Use MIL-HDBK 217?
Join Chris and Fred as they discuss MIL-HDBK 217F contains lots of estimates of failure rates of different types of electronic components (tantalum capacitors, surface-mounted resistors and so on). Which was released in 1991 (i.e. … a long time ago) and is nothing but best guesses by faceless people. So what happens when customers demand you use it? Bad stuff.
- It makes your system less reliable. True story. If a customer demands you use MIL-HDBK 217F, then you are essentially forced to use the types of components in those handbooks that have the best failure rate. But the pecking order for today’s electronic components has changed remarkably (remember that MIL-HDBK 217F came out in 1991). So there are lots of manufacturers who knowingly take out more reliable components and replace them with components that have a better failure rate in MIL-HDBK 217F. Madness.
- It makes you stop thinking about reliability. Looking at you defense and governmental customers. Instead of you actually learning about what you need to look for in the products your suppliers give you, you just want a number that you can put in a report. So you essentially tell your suppliers that no matter how hard you work on the quality and reliability of your components, they will always be assigned the same arbitrary, outdated number. Lots of madness.
- Where did the numbers found in MIL-HDBK 217F come from? There is no formal answer to this question. But industry insiders know that it is based on the precious few companies (perhaps as low as five) who were willing to share their reliability data (without knowing how robust these numbers were). All the gaps were filled in by historical military data dating back decades (to the 1960s). So do you want to use MIL-HDBK 217F to estimate smartphone or desktop computer reliability based on an ad hoc smattering of data that was put together before anyone knew these products were even feasible? Incredible amount of madness.
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