Plane with GPS but no Compass EKF error

I am using Matek F405-wing FC with 4.0.6 FW. I have unchecked all the known boxes to associated with compass but I cannot shake off EKF errors.
My GPS is 3D-Fix (11 satellites) HDOP 1.04, I can arm it but EKF stays red.

Has anyone solved this problem yet?

image

Disable EKF and you’ll be happy

How do u do that, parameter address please?

AHRS_EKF_TYPE 0

https://ardupilot.org/plane/docs/parameters.html#ahrs-ekf-type-use-navekf-kalman-filter-for-attitude-and-position-estimation

Disable
EK2_ENABLE
EK3_ENABLE

https://ardupilot.org/plane/docs/parameters.html#ek2-enable-enable-ekf2
https://ardupilot.org/plane/docs/parameters.html#ek3-enable-enable-ekf3

Others EKF parameters :

https://ardupilot.org/dev/docs/extended-kalman-filter.html#extended-kalman-filter-ahrs-ekf-use

@RizHass mind that on setups with no compass, your EKF requires a GPS velocity vector to align yaw. this won’t happen until your airframe moves forward, so the final EKF yaw alignment will not happen until after takeoff, just a few moments into your flight:

ekfYaw

so i personally would suggest to not disable EKF. make sure to have your arming checks set to default 1 (= all enabled) and you’ll be good to go.

It’s different behaviour,
if you want to fly as plane 3.4 : straight on track when using mission planning > disable ekf
If you want smooth flight et large drift > enable ekf.
I personally hate ekf for mapping purpose …

@kikislater with respect to EKF being one of ardupilot‘s key features i just think opting to not use it should rather be a matter of individual use case and preference than a general support forum advice.

Up to you, it’s just my opinion … Make what you want with this !

Is its realy on-track or is is just showing that it is on-track but in reality is a bit off?
Youtr input is valueble because it comes from experice with real-world measurement equipment. Thanks.

It’s on track in log file after flight whereas with EKF two tracks could overlap