When do you "dispatch"?
You are governed by the requirements of the aircraft MEL (with regard to aircraft deficiencies) up until the point at which you dispatch.
When does this happen?
My feeling is that is at the start of pushback, but have also been told that it is when the aircraft first moves under it's own power, or alternatively, at the start of the take-off roll.
Does anyone have a reference for this?
thanks
Jim