I've been doing a lot of mapping using mission planner to set up the lawnmower pattern over the subject area. Things are going well, but most of these jobs need every bit of efficiency. To that end, is it possible to perform a banked turn at speed rather than slowing down and turning? We usually fly 11-12m/s at 60 to 90m. The copter slows down, does a turn and then heads to the next turn. Seems like things would go a lot faster if it could just hook around the ends.
Set up your survey grid as normal in Mission Planner. Then on the waypoint table at the bottom of the screen on each drop down change from WAYPOINT to SPLINE_WAYPOINT and it will change to curved turns. You probably won't notice much improvement depending on your overlap, however.