The Ops manual is the Bible. Approved by your aviation authority for your companies specific operations. The only time it isn't gospel is if it countermands or conflicts with something in the
Limitations section of the RFM or dash 10.(rare these days)..Although this requirement can be overruled by a specific 'operations specification' ...Command seat position, or crew requirements in external load ops as an example...This may well be in the Limitations section but can be countermanded by Ops Specs in approved circumstances.
It used to be only in the US that the 'prudent man' rule applied, and if you were in Europe and following the written rules you were safe...But I was talking with a JAA ops inspector in Marseilles last week, and he said there are moves afoot in Europe that if you conduct an 'imprudent' operation they can still nail you even if it's in compliance with a written regulation, but that the written regulation would be considered imprudent by a jury of your peers (or words to that effect)
So it seems that prudence is the catchword! (wonder what it means?
170'