Actuator,
Good operators use Precision Timing Schedules. Google it. This is one of the first 3 URLs:
http://www.google.com.au/url?sa=t&rc...0gSfyIEPOpsPPg
Good operators try not to "cook the books" too much, as there are invariably operational and financial penalties that are attached to delays.
Not all regulators are like the CAAUK - not all regulators approve schedules for regular public transport operations and I suspect none worry about
ad hoc charters. So that leaves the door open for some operators to schedule unachievable turnaround times.
So, what to do about it?
That depends if you have an interested union, interested regulator or interested Safety Board. If you feel secure enough, you can always ask your Flight Ops Manager what his/her expectation of you is when the schedule begins to slip and what are the contingency arrangements in place if fatigue prevents discretion being exercised...
Oh, and it was a good question with a simple answer!
