Takeoff for a Mission Mode

Please describe the definition of “Takeoff waypoint” in the world of QGControl in relation to a quadcopter VS fixed wing. I am flying a fixed wing with PixhawkMini and it flies very well in stable, RTL modes, but mission mode works at sometimes and some times does not. I arm, flip auto mission switch on Tx, hand launch, motor kicks in, plane flies off perfectly, but rather than going to the waypoint #1, its start circling. I have done several auto missions on my quadcopter without any issue but fixed wing is hit and miss.

Just to further elaborate, should the takeoff point for a fixed wing aircraft be at the hand launch location or further away from the hand launch location (how far away, how high, pitch angle, etc.)?

It would be very helpful to have documentation describing the difference in mission mode for fixed plane and quadcopter.