Land Mode Not straight down

Hi All,

I been having some TX problems lately causing the copter to go into Land Mode (fail safe)

I found however that sometimes it does not go perfectly straight down, instead it descends diagonally (and when it does finally get close the ground usually flips over because of the sideways motion).

But it really spooked me when it start moving sideways at a faster rate then it was descending, making the copter go closer and closer to a fence that would make it difficult to get after.

Luckily I regained TX and managed to land it manually.

I though LAND was supposed to go straight down? is this correct?

Not to sure how to even start to debug this


I expect its triggering that land command whilst in motion says its moving several m a second when failsafe triggers land it will try and get back to that point where the trigger happened.

It goes without saying that you should sort your radio out before flying again.

Yes im not sure what’s up with the radio the range seems to be very limited about 20 meters. Don’t even know where to start on that one either.

BUT for land mode, the copter did not show any signs of even thinking or returning to where the trigger happened, in fact I had to chase after it, reset my TX, get control back and pull back the throttle or it would have jumped the fence.

If what you say is true then there is def something wrong.

There is no question that the copter knew where it was.
Here is the altitude graph and mode graph
It flipped from RTL to LAND and then decided to fly away!

Here is the google map of what happend. Purple is RTL, Red is LAND and Orange when i finally got control of it (which was more of a fall from the sky then control :slight_smile:)

So any idea what i shoudl be looking for?

Im taking a stab but im guessing that

RTL kicked in due to GeoFencing of top limit of 15 meter
Land kicked in when it dropped to 10 meters

Still dont know why land would take it course like that

I have the same problem.
The transmitter is a HK T6A V2. It worked well for two years and in spring suddenly it reaches not more than 10mtr. First I didn´t know what´s happens, the coper falls from the sky. So i activated failsave and I lose the contact direct after landing and the copter crashed while try to find the RTL position on the ground :frowning:.

Now I have a other transmitter and make some tests for failsave and have the same problem like you have. The copter runs away sidewards in case to land on the position where I turn the transmitter off.

PRoblem is the copter is NOT trying to go back to where it lost connection. IT flights towards a place it never been before.

I posted Telemetry and Data Flash logs at … ad-of-land