Well I can tell you from experience, a Chieftain will get out of Birdsville off the dirt runway with full flap. It won't accelerate much once airborne and it won't climb much until you bleed the flaps up...carefully, but it will do it.
Amazing what last minute distractions can do to you. I'm actually surprised that no-one commented at the time given there was a long line of us leaving after the races.
