POS Alt USE GPS Instead of Baro (EK3_SRC1_POSZ is 1 = baro )

[moreba1]

Bug Report

POS Alt use GPS altitude Instead of Baro altitude . POS.RelHomeAlt is correct but POS.RelOriginAlt is not correct. I think EKF uses GPS ALT for calculating Origin alt and it causes altitude error and is not good for flight.

AHRS_EKF_TYPE = Enable EK3
EK3_SRC1_POSZ = 1 baro
EK3_SRC2_POSZ = 1 baro
EK3_SRC3_POSZ = 1 baro

Version
Arduplane V4.5.7

Platform
[ ] All
[ ] AntennaTracker
[ ] Copter
[ X] Plane
[ ] Rover
[ ] Submarine

[rmackay9]

Hi @moreba1,

Thanks for the report. Ideally these should go into the support forums first and also 4.5.7 is quite old now. Also it's best to include a log file.

I wonder if you could re-test using 4.8.0-dev (aka "latest"). We've recently merged this PR which may resolve the issue.

[moreba1]

I wonder if you could re-test using 4.8.0-dev (aka "latest").

Hi @rmackay9

I tested with 4.8.0-dev version. but the problem was not solved.
EKF calclated alt , POS.Relhomealt and BARO.alt is correct ,
but POS.RelOriginalt and POS.alt and NTUN.ALT Error is not correct and Use Wrong GPS Alt .

why POS.RelOriginalt and XKF.PD are different ?

Log:

2026-06-17 23-35-07.zip