First APM "fixed wing"

Hello all;

I sure hope I posting in the right place.

I want to build my first APM/FPV airplane. I have had no success with the APM on a Quadcopter even though I can fly my 4 KK2 board quads just fine.

I have been flying RC for about 10 years now and have mostly foam planes. I have several suitable (I think) platforms to put an APM 2.5 in. I have three APMs from RCtimer. GPS and telemetry (use 915Mhz).

I have a seaplane called a Great Planes “Seawind” that I have flown quite a few times. It has a large equipment bay and parts are available from Tower Hobbies. I ordered a replacement canopy and mounted a full size servo in the top of the canopy by cutting a hole to fit. I am mounting a 808 Keychain camera on top and drive it with the knob on a ER9X system.

I have several Windrider EleBee’s and they are actually my favorite planes to fly. I have seen some folks modifying these on another forum and think I will take my oldest, lowest airframe time, EleBee and convert it to a brushless motor and ESC. I think I can fabricate the new aluminum mount for the motors. This plane is still set up on 72 Mhz. I am told this is a good thing for longer range flights. I have a Futaba 7 channel with PCM function. (same camera setup except the servo will be on the Rudder channel. I think this will be very cool) :slight_smile:

The point.

Should I use the latest version of the firmware or one of the older versions?

Where do I find the settings for a Delta/Vtail airframe?

What flight modes are recommended for newbees?

Where should I start reading?

Does the APM need to be mounted right at the CG point in a fixed wing?


I’m sure I have a lot more questions!


CG - best to mount it as close as possible to avoid any funky influences.

Have a look here for configuration files … rframes-2/ you will of course have to tune them as they won’t be perfect.

Everything you need for tuning is here

Thanks, I’ll look over the info. I think my APM is going to end up a little forward of the CG. It will be on center-line and mounted in the correct axis. I think that will have an effect on pitch and yaw correction in the seaplane but the wing has no rudder. I guess tuning will take care of these issues.

Cool, let us know how you get on

Hi Sudsy, actually as long as the flight control board is squarely aligned with the fuselage and flat relative to the ground reference of the plane in flight (not tilted) it will work fine and should not require tuning for not being aligned with the CG.
If you think about it a bit you can see why this is true, say you have it located ahead of the center of gravity, OK when you pitch up the board is going to move up slightly, but that is completely irrelevant, what the controller is paying attention to is tilt and it is the same tilt no matter where the board is located on the plane.
This is also true for roll and yaw.
I think this is often misunderstood, but you can pretty much have your flight control board wherever you want it on the plane, because the effective displacement of the board in tilt and direction is the same.
Mostly you want to keep it away from vibration and to ensure that the GPS is in the clear and the Magnetometer is sufficiently far from any DC wiring so it is not adversely influenced.
generally you are better off keeping the flight controller located along the center line of the fuselage, because on GPS where the center of the flight controller is determines the middle of the airplane.
(If it was out on the tip of your wing and you were doing an auto landing you would be displaced 1/2 wing width to one side.)

Is it even possible to see an half a wing width of displacement when landing?? If so we need to talk. On a good day I might be able to land within 50 feet.