Two settings both decide how RTL ends

What ArduPilot says:

• PreArm: unset one of RTL_AUTOLAND or Q_RTL_MODE

RTL_AUTOLAND (not 0) makes RTL continue into the mission's landing sequence; Q_RTL_MODE (not 0) makes it end with a VTOL landing at home. With both set it is not clear which should win, so 4.7 refuses to arm. 4.6 has no such check: there the outcome depended on which condition was met first.

What to do, most likely first

1. You want RTL to end in a VTOL landing at home.

   FixSet RTL_AUTOLAND to 0 and keep Q_RTL_MODE: 1 flies home on the wing and switches to QRTL near home, 2 adds a circling descent and an approach into the wind, 3 switches to QRTL at once.

2. You want RTL to fly the landing sequence planned in the mission.

   FixSet Q_RTL_MODE to 0 and keep RTL_AUTOLAND.

A mission that holds a DO_LAND_START item needs RTL_AUTOLAND set (another pre-arm check says so), so in 4.7 such a mission and Q_RTL_MODE cannot be used together.

Parameters to look at

Where to do it:Mission Energy Check