Hi pwagner,

Thank you for your reply. This is as I expected with regards to the base component failure rates. If you wouldn’t mind, could you give me any more details on why the following wouldn’t work?

Example:
If I used the 217plus models to output a MTBF figure on a component-by-component basis, couldn’t I convert this figure from calendar hours to operational hours and then calculate the FITs for each component that way?

i.e. FITs (component) = 1000000000/MTBF (component)

Couldn’t I then use this FITs figure, convert to failure rate, and use this as an input for the component failure rate in the MIL-HDBK-217 models?

My research hasn’t uncovered anything but it would be best if I was able to prove it.

Thanks for your help.