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Descending lower than your start height without landing? (Disable auto land?)

pfrogbot

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Hi I live on a hill and usually launch from the hill at some point. I would like the ability to fly down the hill at ground level however, due to the way the drone registers its starting altitude as 0, it ends up at like -5 or -10m below and then I keep pushing the stick (because it's not actually anywhere near the ground) and it goes into landing mode.

I was wondering if there was a way to either disable the auto landing mode when I pull the stick OR to reset ground to be lower somehow?

I contacted DJI support and they recommended resetting the home point however that's not super helpful because I would basically have to keep pushing it lower then, right before it tried to land, reset the home point and keep doing that I guess?

I did also try launching from further down the hill but I can only really get to like the halfway point on the slope so there's still a bunch of land below me I can't get anywhere near.

Ideally I'd just be able to flick some switch (in the DJI fly app) that instructs the drone to never auto land from stick input, then when I want to actually land, just flick the switch again. Not sure that's actually possible though in any way. Hoping y'all can advise.

Thank you!
 
I routinely fly below takeoff altitude, and have never had an issue with autolanding. Autolanding requires the visual and IR sensors to see ground, if I'm not mistaken. and a full down press and visual sensing is required to start landing.

How close to the ground are you staying as you fly downslope? If trying to skim the ground and that requires full down on the throttle control, then you are essentially trying to land.
 
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The drone should NOT enter that landing mode when NOT near the ground. I have not descended to significant negative heights with a Mavic but I have descended to near -200m with a Phantom without problem.

The drone should ONLY enter that sort of landing mode when sent to LESS THAN approximatley 50cm above the actual ground directly beneath it.

However, be aware that when descending into something if the drone loses sufficient GPS satellites it may enter a flight mode that can prevent it from climbing out of the something. There are a few threads in here where that caused the pilot considerable difficulty, i.e. keep an eye on the satellite count and don't go too deep into narrow valleys, canyons or gorges etc..

I do not know if the downward looking sensors of the MA2 can be disabled but a work around would be to cover them with tape and stop them working altogether. Or perhaps and possibly better, cover just the IR sensor, that was suggested in here? somewhere.

That said I would suggest it is more important to establish WHY your drone is entering that landing mode if it is truly well clear of the ground.
 
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This is interesting! I have seen this multiple times but didn't realize it wasn't normal. Here's a video of it happening the other day, I did edit the actual attempt to land out but the jump happens because it panned the camera up and started trying to land. Obviously the camera makes it a little hard to tell exactly how far it is from the ground but it appears significantly higher than 50cm. Like at the very least it's at least 3-4 deer in the air.
(timestamp 0:29 if it doesn't work)

There's no hill or anything underneath it. I was watching it but it was a decent ways away and getting pretty dark out. This was right before I flew back to land.

What ended up happening was I was trying to force it lower towards the deer and it turned the camera upwards and said "Landing" and I had to tap to cancel the landing. I do suspect the visual sensors were having some issues making sense of things since it was dark but the downward sensor is IR, right?

What I'd like to do is be able to get closer to the level of the deer and, rather than chase them, try to stay just outside of what'd scare them and be able to get some cool footage of them hanging out.
 
I'd suggest you either post the flightlog for that flight here or up load it to
DJI Flight Log Viewer | Phantom Help (there are also instructions on that page that tell you how to retireve the log)
and then post the URL of the resulting page here.
The log may allow some of the wizards to tell you what was happening.
 
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I'd suggest you either post the flightlog for that flight here or up load it to
DJI Flight Log Viewer | Phantom Help (there are also instructions on that page that tell you how to retireve the log)
and then post the URL of the resulting page here.
The log may allow some of the wizards to tell you what was happening.
Thank you I'll try to do that!
 
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Per the manual that comes with the drone, the vision system can see down about 60 meters, the IR as much as 8 meters. For precision landing the drone needs to ascend to 7 meters or more so it can record the terrain. These things hint that landings are done from 7 meters or 20 feet or so off the ground. Above 20 feet, I can't ever recall my Air 2 drone trying to land except when it was in RTH.

ps:
1647654942474.png
 
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There's no hill or anything underneath it. I was watching it but it was a decent ways away and getting pretty dark out.
The sensors were probably having trouble with the available light, that may have been the issue with the combination of down stick , negative altitude, and landing protection turned on.
 
The positioning sensor might have had problems with available light but I have a vague recollection that the 'visual/IR' height sensor or sensing works in the dark.
 
So this just happened to me yesterday morning. It was about 10am in Long Beach, CA, and I launched my new DJI Mini 3 Pro from the roof-top pool deck on the 17th floor of my friend's apartment building.

Got it up, ascended about 6 feet, moved forward over the railing, then pulled the stick down to descend. At that point it was hovering 17-18 stories above an empty parking lot with no obstacles anywhere nearby, but once it got down to its takeoff height, it refused to descend any further and the prompt kept saying "Landing" and I was like, "wtf, no!" and had to quickly hit the button to cancel the auto landing.

This happened over, and over, and over, and over and over. A good 20 times. Shut the drone down. Swapped batteries. Flew to a completely different area. Still, just kept hearing "Landing" when trying to descend. It would occasionally get down to maybe -3 feet from takeoff height, but that's it.

I did eventually figure out I could trick it into descending lower by popping it up, throwing it into sport mode, going forward over the railing and *immediately* down into descent. Even then, though, switching back to normal or cine modes, if I came back up above takeoff height and then tried to descend again, I'd hear "Landing" and once again, say "wtf, no!!" and quickly cancel the automatic landing.

I'm not sure what's going on with this?! Ideas?

The only thing I can remotely think of is that it was a little bit hazy with the marine layer, but it was clear enough that there was still pretty much perfect visibility all the way to the ground. So unless the water vapor particles in the air were interfering with the sensors and tricking it into thinking it was hovering directly above the ground, I'm sort of at a loss here. However, even if water vapor in the air does end up being the explanation, that's kind of unacceptable.

Attached is a frame from the video from that morning showing the building I launched from, along with the empty parking lot I was trying to descend toward.
 

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See post #5, the OP didn't bother posting his flight log, maybe you will.
It should show what's going on with the drone systems at least.

It really seems like you have a bug somewhere, possibly just a reload of firmware needed, but your issue is obviously not caused by lack of light.
Could be a defective aircraft thing, so too the OPs with a different model.

As a side noted, flying there is pretty risky with all kinds of thigs able to affect a drones systems.
 
So I looked at the Flight Report and it looks like the VPS and IMU weren't agreeing about the altitude, with VPS randomly going from "N/A" to showing between 0.5 and 3.5 feet, while the drone was WAY above ground level. So I'm pretty confident it was mistaking the reflections of infrared light off of water vapor particles in the air for proximity to the ground.
 
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