APM is an amazing piece of hardware and software. i was very impressed to see the prcise naviagation the aircraft does. To get precise navigation and stabilization the aircraft should be very well trimmed in manual mode by making long duration flights. How I do my trimming is I take the aircraft high in manual mode.Then i cutoff the power to zero. I keep it in head wind in glide and trim for yaw by rudder trim. do not trim in crosswind since crosswind causes yaw. I then i give throttle at cruise speed and then trim for counter roll by only aileron trim and this too in headwind. single engine aircrafts with big propllers have significant counter roll. Besides this most pusher aircrafts have downthrust on throttleup. Mixing Throttle with positive pitch with the Tx is a easy way to counter act the downthrust. The pitch mixing is typically +1% to +6% of elevator depending how high the motor is mounted above the CG. this would need some trial and error flights. If all the trimming in manual mode is well done the auto stabilizatoin and navigation is generally quite precised. The same throttle pitch mixing should also be done for automode using Mission Planner.
Agreed - APM is amazing - but it can only work with what you give it. I am a drone newbie and have spent a number of hours flying my APM around the room on a piece of wood to get my head around what it does. Although I have a shiny new toy still in its box in the corner, which will be the eventual home for the APM, it is going in my tatty old Bixler first on the basis that the plane is tried, tested, trimmed and - frankly - an expendable foam box protecting my $300 investment.
The APM will be software unmodified and with a low sensor count, just the GPS, when it flies for the first time (K.I.S.S). I will add airspeed later and get used to the various modes before the whole shebang goes into the new model. I might be adventurous and eventually programme a few of waypoints (most likely geofencing!)
Using this approach all those confusing variables (excuses), that spring into your head when you just miss the ground, have been reduced to pilot error.
Once it all works it will all go into the shiny new toy - another Bixler - just kidding folks - a Bixler 2.