FixedWingLandDetector: force to landed during runway takeoff

[mahima-yoga]

Solved Problem

Takeoff detection occurs when the vehicle is !_landed. During a runway takeoff, it's possible that one of the conditions to be landed is no longer met and premature takeoff is detected. This unlocks the integrator and can start introducing unwanted control surface deflections.

Solution

As we do with hand/catapult launch detection, we can use the knowledge that we are in an auto-takeoff mode inside the land detector. This PR:

• Adds the runway_takeoff_state to the FixedWingRunwayControl.msg
• Renames the fixed_wing_runway_control_s::STATE_FLY to fixed_wing_runway_control_s::STATE_FLYING. I think it's nicer and then it's the same as the launch detection state.
• Forces the vehicle to landed state to stay landed if runway_takeoff_state < fixed_wing_runway_control_s::STATE_CLIMBOUT
• Some minor cleanup

Changelog Entry

For release notes:

Feature/Bugfix Force fixed-wing vehicle to landed during runway takeoff

Test coverage

Flight Test

With LNDFW_AIRSPD_MAX=6 and LNDFW_VEL_XY_MAX=5. We stay landed until the climbout phase.

SITL Tests:

1. General takeoff test (log):

2. Force runway_takeoff_state to CLAMPED_TO_RUNWAY in code (log):

[github-actions]

🔎 FLASH Analysis

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Updated: 2026-01-14T15:40:14

[mahima-yoga]

Thanks @sfuhrer! I added your suggestions, once approved I will clean up the commits