What is the difference of Q_RTL_ALT_MIN and Q_RTL_ALT

ArduPlane VTOL Plane
1

Hi friends, ı could not get what the use of Q_RTL_ALT_MIN is different from the Q_RTL_ALT. Is there anybody experienced with this?

I need clear explanation. The documentation was not cleared enough.

2

Q_RTL_ALT is simply the normal RTL altitude for the drone.

Q_RTL_ALT_MIN only works if you are already in VTOL mode, and you are closer than 150% of the the larger of the WP_LOITER_RAD or _RTL_RADIUS. It is the minimum height the plane will climb before it comes home.

For example: assume the following settings:

Q_RTL_ALT, 80
Q_RTL_ALT_MIN, 20
WP_LOITER_RAD, 100
RTL_RADIUS, 100

example 1: You are hovering in Q_LOITER mode, 10m alt, and 50m away from the home point. If you trigger Q_RTL the plane will only climb to 20m, stay in VTOL mode and return home.

Example 2: You are hovering in Q_LOITER mode at 10m alt 175m away from the home point. If you trigger Q_RTL the plane will climb to 80m before returning to home.

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