Plane 4.2 beta release

@tridge according to the docs there is no “-1” on RTL_AUTOLAND and QGC has no option to set it to -1.

Are we trying to implement a general solution for a specific problem? What exactly caused “it didn’t”, and what was the unusual flying location?

I don’t know if you’ve seen my post about a crash I had when my plane did an RTL after it had landed (caused by the geofence being too close to the runway). Geofence breach RTL after landing = crash

I’m not trying to change the subject, just thinking that the whole auto land design maybe needs some thought end-to-end, including input from @iampete and @WickedShell and others, rather than just patching individual issues with possible unintended consequences.

Sorry that’s the wrong post - hang on, I’ll fix it. Ok - fixed. Geofence breach RTL after landing = crash.

I could live with that. Then it’s a user choice one way or the other to set it up or leave it. It will need a wiki update. I should learn how to do that just to help out…


Are you sure? How about this? You are landing a quad on a ship … an unexpected large wave buffets the vessel just as you are about to touchdown with the quad. You abort the landing - but you still want to land - so - go around? (start again)?

@timtuxworth see the special ship landing mode in 4.2, which has abort

So does this mean we need to get QGroundControl changed? If it’s data driven I guess it might work, but right now there is no option in QGC to set RTL_AUTOLAND to -1

Admittedly I’m not a regular user of QGC. I mostly only use it from my iPad in the field with a few vehicles. But I think you can use the “advanced settings” in a parameter to override the basic choices.

Oh I see you can do that - you have to select “Advanced Settings” and then “Manual Entry” - so this means that for the wizard generated drag and drop landing in QGC, it will always throw this error on arming and the user will have to figure out that they need to manually override this value.

It kind of defeats the “user friendly” idea of having the landing setup wizard no?

I use QGC whenever I can, mostly because I got rid of my last Windows machine more than 10 years ago, I only have Macs, one in the office, one for the field.

i’ve updated the PR so there is a new RTL_AUTOLAND=3 that disables the arming check and allows for go-around usage of DO_LAND_START

So that would be the same as the -1 you mentioned before?

yes, both -1 and 3 will work, I just decided to make 3 the one that will appear in the dropdown menu when setting the param

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That makes sense. I’m good with it. Thanks!

I’m struggling with how to describe this in the docs. RTL_AUTOLAND = “Automatically begin landing sequence after arriving at RTL location.”

So the table would look like this:

Value Meaning
0 Disable
1 Home - Enable fly HOME or to a Rally point then land
2 Land - Enable go directly to landing sequence
3 Go Around - Disable but allow Arming with DO_LAND_START in the mission for go arounds.

This is because in QGC - only the first part of the text is shown, so the options will all look the same otherwise. Here is a screenshot:

close, but on (1) a rally point may be used

I just copied what was there

thanks, i’ve updated the PR to clarify

Are the docs generated from Parameters.cpp? If so can I suggest you use the text I have put above, including the rally point , I think (maybe), it’s clearer than just “OnlyForGoAround”. I added a screen shot to show why it’s important.

I’ve just released ArduPilot Plane 4.2.0beta4. Several important fixes are included since the previous beta, plus some new features.

  • added BATT_OPTIONS option to send resting voltage (corrected for internal resistance) to the ground station
  • fixed a bug when a blended GPS is lost, where the wrong GPS could be used for a short time
  • prevent rapid RTL/AUTO switching with DO_LAND_START and fence breach
  • added RTL_AUTOLAND=3 to prevent arming check about DO_LAND_START with no RTL_AUTOLAND
  • fixed yaw in AUTO mode on the ground on quadplanes when using rudder to disarm
  • fixed failover between IOMCU RC input and a secondary RC input on a uart
  • display source of RC input with protocol
  • fixed DShot reversal bugs with IOMCU based boards
  • fixed battery remaining percentage with sum battery backend
  • added KakuteH7-bdshot
  • added terrain reference adjustment and TERRAIN_OFS_MAX parameter
  • fixed param conversion bug (impacts airspeed enable)
  • changed MatekH743 to use a 32 bit timer

Happy flying!


Where can I find any details to “DJI FPV OSD multi screen and stats support” please?