The VTOL transition command was refused

What ArduPilot says:

• VTOL transition only in AUTO
• Invalid VTOL mode

DO_VTOL_TRANSITION tells a QuadPlane in AUTO to fly the mission on its lift motors (value 3) or on its wing (value 4). “VTOL transition only in AUTO”: the command arrived in another mode. “Invalid VTOL mode”: its value was neither 3 nor 4.

What to do, most likely first

1. The command was sent outside AUTO, for example from a ground-station button while in QHOVER.

   FixOutside AUTO, change the flight mode instead: a Q mode to hover, FBWA or CRUISE to fly on the wing; the transition happens by itself.

2. The mission item or the script sends the wrong value.

   CheckRead the item's first parameter.

   FixUse 3 for multicopter flight, 4 for fixed wing.

Where to do it:Mission Energy Check