Not all main outputs work on Pixhawk


I am currently using the pixhawk to control a nutball plane. I am using a Spektrum DX8 with the DSMX satellite receiver to control the pixhawk. Using Mission Planner (version 1.3.5) I uploaded the ArduPlane V3.0.3 to the pixhawk. I then calibrated the radio and all the green bars move for all the controls I have programmed (channels 1-7.) However, when I power up the pixhawk using a 3s lipo, only the first four servos (channels 1-4) move.

I’m new to this and need some guidance. I’m sure there is something I forgot to do, but I cannot figure out what. Help please!

I would say that you are taking a chance using just the Spektrum Remote Receiver with a plane.
It does not have the same range as the Spektrum standard receivers.
You might want to consider using a PPM encoder with a standard Spektrum receiver in place of the Remote Receiver:

To be able to use the additional R/C channels, you will need to view all of the Arduplane parameters by using the Full Parameter List in the Mission Planner. In the Full Parameter List you can enable the other R/C channels.

Thanks for your help!