Flew today after the rain and fog was still lingering in an around the treetops. I am aware that haze and fog can throw of the sensors, so I paid close attention. Sure enough on the way up Spark engaged auto landing.
30 feet up and the sensor read 0.3 feet.

No problem, I still had full control and started descending, however I was entirely unable to cancel the auto landing, not by hitting the red X on my screen or hit pause on the remote. After ascending about half way down the warning disappeared.

This bugged me, I thought it was a fluke and tried to replicate this. About 30 feet up and the app prompted auto landing again, not being able to cancel it.

Given I was in line of sight and had full control over the bird this wasn't much of an issue, however if this would have happened a few hundred feet away this could potentially lead to a disaster.

Just curious why one can't cancel the auto landing in mid air.
I have tried to stress the battery once and continuesly and successfully canceled auto landing on low battery (hovering 2' over the ground) just to see how long it would stay airborne. No issues here.  

Anyone else experienced this? In my opinion you should always be able to cancel / pause / override anything the drone does.

Ps. Totally worth making out out after the rain though - Fall in all its glory.

When I did my dense fog test I didn't have any issues with auto landing, but when I started descending in normal mode I went into landing mode and descended very slow. Switching to Sport Mode allowed me to come down.  Now this was very dense fog and I went straight up from my deck.  Couldn't see Spark for about 300 feet of altitude, but I could hear it and had it on my map.  So very little if any lateral movement.  The fog was way denser than the beautiful photo is showing.  

Actually, after the topic "landing in a cloud" (falling from xxx feet, b/c auto landing) I was thinking about this.
And asked myself, if it could be overruled by rising again or flying it forward, backwards maybe even in sportsmode.
Seems, I found the answer.

Actually I expected this, since in another topic about it there was no reaction at all from DJI. If I recall it right!

JCStorbeck Posted at 2017-10-14 17:14
When I did my dense fog test I didn't have any issues with auto landing, but when I started descending in normal mode I went into landing mode and descended very slow. Switching to Sport Mode allowed me to come down.  Now this was very dense fog and I went straight up from my deck.  Couldn't see Spark for about 300 feet of altitude, but I could hear it and had it on my map.  So very little if any lateral movement.  The fog was way denser than the beautiful photo is showing.

Mhhh, now I am confused!

So you could "stop" landing mode, by switching to sport?
But thats interrupting a landing, not autolanding, mmmmhhhhh!

This also happened to me last weekend up at the lake near Birchwood Wisconsin. I wasn't sure at the time why I couldn't cancel autolander but now I think that it was the fog now that you shared your story. Wonder why the fog causes this. You can see the type of fog I was flying in at the very end of this video.  

I went back and looked at my flight into the soup.  I went up vertically 120 meters in sports mode.  Got to 120 meters and turned off sport mode since I didn't want to accidentally  travel laterally too fast and as soon as I did that Spark went into landing mode at 120 m.  I switched to sport mode after a short time once I figured out what was happening.  

Don't know hown thick the fog needs to be to affect this, but these two photos don't look like it was much fog.  

The downward looking sensors do like a pattern in texture and color and lighting in a certain fairly wide range, so fog is all wrong for those sensors.  

DJI recommends not to fly in fog or at least be very cautious..

Please check our user manual and fly in good weather for your spark safety. Please try to fly in recommended environment and see if the autolanding come up again. Keep us updated, thanks.

Elektra- the auto landing is not an issue - not being able to cancel it is.

As far as I am aware the only instance whereby auto land can not be stopped is when the battery reaches 10% power (critical level) or if there is a fault with the battery - I hope no moisture got into the drone/battery and caused a malfunction - you shouldn't fly in fog or rain - LiPo's can explode when exposed to moisture. Cool pic though.

From personal experience you can cancel the auto land on low battery until and passed the battery reaches 0% with no issues.
In the stated scenario the battery was fresh and at 90%.
Also the fog/mist was very light yesterday.
The issue was that auto landing blocked the screen and no user was completely denied.

My point is, as stated before - any auto feature should be able to be canceled by the pilot.

This was initially a problem with Mavic, the temporary solution at that time was to switch to sport mode this cancelled the landing, it has since been corrected with FW update, hopefully it will be the same for spark, you certainly don’t want this happening when flying over water.

Flying over water is my main concern with this, hopefully the engineers will put this in to consideration and fix this.

I had the same problem today.  Clear sky.  No wind.  It because "stuck" about a foot off the ground on cancelling the landing.  The red "X" cancel, then did nothing.  No other controls would respond.  I could put my hand under it, raise it up to 3 feet, the landing slider would appear, I'd slide it, it would descend, but still not land.  I had to wait until the battery died and it landed itself.

Dr Tony Burns Posted at 2018-8-12 23:12
I had the same problem today.  Clear sky.  No wind.  It because "stuck" about a foot off the ground on cancelling the landing.  The red "X" cancel, then did nothing.  No other controls would respond.  I could put my hand under it, raise it up to 3 feet, the landing slider would appear, I'd slide it, it would descend, but still not land.  I had to wait until the battery died and it landed itself.

You can grab the drone from underneath and be careful and turn it over (upside down) and it will stop the motors..   

The sensors do funny things on the Spark.   Don't like Fog , Don't like snow, Don't like shiny reflective surfaces.    I was flying in the garage and the front obstacle sensors were saying something was 2m in front of me and it wouldn't allow me to move drone at all with RC.  It was just stuck there.    I had to grab drone mid air and turn everything off..