My ?: I can see how one can allocate downward reliability however having
trouble grasping how anything with maintainability can also be allocated
downward. I can see allocating reliability to the lower levels and then
adding in respective downtime at that level to calculate Ao but again -
allocating Ao? Do? Tough one for me. Can you comment please?
Operational Availability can be allocated from the Top Down.
See https://acc.dau.mil/CommunityBrowser.aspx?id=637655 for a model developed to do just that. Note that a link is provided identifying contact information of the owner of the model. They should be able to speak more in-depth as to the algorithms used to perform the calculations.
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