I have six FM’s programmed on my APM 2.5 in Mission Planner. Mode one(1) doesn’t behave like the other five modes. Modes 2-6 I can choose Stabilize, Land, Auto, RTL, and Land no problem. The box with the mode name is green color for modes 2-6. Mode one box with name is blue color. I want mode one(1) to be Position Hold. I put this name in the box and it indicates “unknown” at top of FM programming screen and also on Flight Data screen. PWM value for mode 1 = 1167 which is well within limits. I can get mode 1 to accept Altitude Hold but not Position Hold. Even with Altitude Hold the box is still blue color. APM is set for Quad in “X” configuration. Again, any help appreciated.
I seem to recall that we don't allow "auto" (GPS-guided) modes in position one, for safety's sake, in case GPS data is lost. (That's certainly the case in ArduPlane)