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Flying up into the fog

larryc43230

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Columbus, Ohio
We had a very pretty fog settle into the neighborhood this morning. I got out my trusty still camera and got a few nice shots, then began wondering what I could get with my Mavic Air.

I sent the drone straight up from the driveway in front of my home. I was hoping to get it above the fog bank, but that never happened. My location is just a few miles from a major airport, and partly because of that I had the maximum altitude set to 400 feet. When the drone reached that height, it was still enveloped in solid fog. I couldn't see much of anything in the view from my remote (the view from the camera).

At that point, I decided to give up and bring the drone back home. I hit the RTH button on the remote, but after coming down just a few feet it slowed its descent and mostly just hovered in place. I used the joysticks to try to force it to descend. That worked, but the descent seemed agonizingly slow. It took much longer than usual to come back to earth. After it eventually descended to maybe 80 feet, it seemed to get its bearings again and landed normally. I figure that was when it started seeing structures again.

Is this normal behavior when a Mavic Air is launched into a fog? Is there a more effective, and hopefully quicker, method to bring it back home again under these circumstances? Maybe sports mode (which I pretty much never use)?

Larry

P.S. Just for fun, I had the drone take a couple of photos while it was at maximum altitude. I would post them, but they look like the view from the inside of a cotton ball. ;)
 
Could be that the fog is confusing the downward vision system when it's doing the RTH ... I'm a Mav' Pro pilot, so the Air is not as familiar, but I'd be surprised if the RTH function is not trying to use the downward vis' cameras as one factor in getting the Mav' Air back to you.
 
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Could be that the fog is confusing the downward vision system when it's doing the RTH ... I'm a Mav' Pro pilot, so the Air is not as familiar, but I'd be surprised if the RTH function is not trying to use the downward vis' cameras as one factor in getting the Mav' Air back to you.
I think you might have nailed it. I did get a couple of error messages about downward sensors. Checking the flight record on AirData, I see the following messages during the descent:

Downward infrared sensor failure. Land as soon as possible.
Downward Obstacle Sensing is not functioning.__Sensing system is blocked or too close to the obstacle.

Looks like the poor thing was lost in a fog. :-)

So, any advice regarding how to bring it back home when that happens?

Larry
 
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You need to disable the downward sensors becasue to the IR sensor fog looks just like the ground, and their purpose is precisely to prevent going into the ground.
Guess I need to find out how to disable those downward sensors. Never had the need to do that before now. :-)

Larry
 
Guess I need to find out how to disable those downward sensors. Never had the need to do that before now. :)

Larry

Bad idea. Better not to fly in the fog to begin with. You dont know where the drone is, cant see where it is, and cant see anything from the camera. Accident waiting to happen, sorry.
 
We had a very pretty fog settle into the neighborhood this morning. I got out my trusty still camera and got a few nice shots, then began wondering what I could get with my Mavic Air.

I sent the drone straight up from the driveway in front of my home. I was hoping to get it above the fog bank, but that never happened. My location is just a few miles from a major airport, and partly because of that I had the maximum altitude set to 400 feet. When the drone reached that height, it was still enveloped in solid fog. I couldn't see much of anything in the view from my remote (the view from the camera).

At that point, I decided to give up and bring the drone back home. I hit the RTH button on the remote, but after coming down just a few feet it slowed its descent and mostly just hovered in place. I used the joysticks to try to force it to descend. That worked, but the descent seemed agonizingly slow. It took much longer than usual to come back to earth. After it eventually descended to maybe 80 feet, it seemed to get its bearings again and landed normally. I figure that was when it started seeing structures again.

Is this normal behavior when a Mavic Air is launched into a fog? Is there a more effective, and hopefully quicker, method to bring it back home again under these circumstances? Maybe sports mode (which I pretty much never use)?

Larry

P.S. Just for fun, I had the drone take a couple of photos while it was at maximum altitude. I would post them, but they look like the view from the inside of a cotton ball. ;)
Very interesting because I was thinking about the very same thing, taking it up in the fog. I guess I won't be doing that.
 
It was straight over my head. I could barely make it out above me visually, but I could still hear the thing. :)

Larry
At that point, you could have cancelled the RTH and manually brought it down to you ... ??? That would have overridden its auto-landing sequence that was struggling with the lack of 'ground'.
 
At that point, you could have cancelled the RTH and manually brought it down to you ... ??? That would have overridden its auto-landing sequence that was struggling with the lack of 'ground'.
That's exactly what I tried to do, but the drone didn't want to come down, either via RTH or manually. I'm coming to the tentative conclusion that it was the inoperative downward sensors that made the drone behave that way. I had the joystick jammed in the "down" position, but It still descended very slowly, until it was able to "see" its surroundings. After that, it landed normally and exactly at the RTH point.

Larry
 
I’ve been wanting to get a shot of redwoods in fog, but was worried about moisture. Was there much of a issue with it on the camera?

Oh yeah- To be legal, dig at least a 401’ hole to fly in if there’s ground level fog! :P
 
I’ve been wanting to get a shot of redwoods in fog, but was worried about moisture. Was there much of a issue with it on the camera?
I'd read about problems other drone pilots have had with moisture after flying in the fog, so I checked the drone (and camera) after it landed. I didn't notice any problem at all in this case. I should mention that the weather wasn't really that wet overall, there was simply some ground fog that disappeared later in the morning.

Larry
 
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