Mission Mode Rejected on Fixed-Wing

Hello,

I’m working with a fixed-wing UAV running PX4 and experiencing an issue where the aircraft does not enter Mission (Auto) mode, despite all primary preconditions appearing to be satisfied.

:white_check_mark: What I’ve Checked So Far:

  • All sensors and system calibrations are completed successfully.
  • After calibrating and before arming, I get the error “compass inconsistent by 136 degress”. When I change the angle of the plane, I arm when this error is corrected.
  • The aircraft arms without any issue.
  • GPS has 3D Fix with acceptable HDOP.
  • Telemetry connection to QGroundControl is solid.
  • A full mission is planned and uploaded, including a TAKEOFF command as the first waypoint.
  • The vehicle is in stabilized flight and can be switched into other modes, but does not accept Mission mode.

Error Messages / Critical Warnings Observed:

  1. critical: preflight fail: compasses 171 degree Inconsistent
    → There appears to be a compass inconsistency warning (possibly between internal and external compasses).
  2. Error: Mission rejected: the landing glide slope is steeper than the vehicle setting of 5.0 degrees
    → Mission is rejected due to an excessively steep landing profile.
  3. Error: Reduce the glide slope, lower the entrance altitude 33 meters, or increase the landing approach distance 449 meters
    → PX4 suggests modifying the landing profile (altitude or horizontal distance).

/// Additional notes

  • using pixhawk 2.4.8 and gps M8N module
  • Using QGroundControl (latest stable).
  • Autopilot hardware: [e.g., Pixhawk px4 v 1.15.4].

What do I need to do to fly autonomously?
Thanks in advance for any insight.

  1. Check your external mag and whether it has the right orientation. Something must be off. Share a log if you can (set SDLOG_MODE from boot).
  2. It complains about your mission, so that’s valid. You might have to adjust the mission, or adjust some parameters to get it to pass. Maybe others can chime in what they are.