diff --git a/plane/source/docs/quadplane-transitions.rst b/plane/source/docs/quadplane-transitions.rst index 1963165cca..a0599d23e0 100644 --- a/plane/source/docs/quadplane-transitions.rst +++ b/plane/source/docs/quadplane-transitions.rst @@ -40,7 +40,7 @@ Transition to Fixed Wing Mode from VTOL - If :ref:`Q_TRANS_FAIL` is not zero, then exceeding this time before reaching :ref:`AIRSPEED_MIN ` airspeed will cancel the transition and the aircraft will immediately execute the action specified by :ref:`Q_TRANS_FAIL_ACT`. The default is 0, which disables this timeout. -.. note:: if bit 19 of :ref:`Q_OPTIONS` is set and :ref:`Q_TRANS_FAIL` is not zero, and if the airspeed is greater than 1/2 of :ref:`AIRSPEED_MIN`, then the transition to fixed wing will immediately complete. This is useful if no airspeed sensor is being used, and the transition is into a headwind, which could prevent an accurate airspeed estimate from being obtained until a turn is made. Without using the :ref:`Q_TRANS_FAIL` timeout and this Q_OPTION, the transition could be indefinitely long since airspeed might be reported as below :ref:`AIRSPEED_MIN` due to low groundspeed. +.. note:: for tiltrotors only: if bit 19 of :ref:`Q_OPTIONS` is set and :ref:`Q_TRANS_FAIL` is not zero, and if the groundspeed is greater than 1/2 of :ref:`AIRSPEED_MIN`, then the transition to fixed wing will immediately complete. This is useful if no airspeed sensor is being used, and the transition is into a headwind, which could prevent an accurate airspeed estimate from being obtained until a turn is made. Without using the :ref:`Q_TRANS_FAIL` timeout and this Q_OPTION, the transition could be indefinitely long since airspeed might be reported as below :ref:`AIRSPEED_MIN` due to low groundspeed. .. note:: The airspeed used during transition can be found in dataflash logs as CTUN.As. This is a canonical value which will include the airspeed sensor if enabled, or use the synthetic airspeed if not.