New Member saying Hi - Herefordshire

So hi to everybody

My name is Leigh Martin

Lockdown put me into a bit of a spin with being self employed and my contract being ended rather abruptly. Mid 50’s isn’t a comfortable place to be in this situation!

Any way used my Govt. help package towards buying a Mavic 2 Pro and PfCO course.

I have now completed the theory and practical assessments yesterday and am waiting for the required paperwork to apply for my ticket with the CAA.

Now it’s time to look for work, gulp.

Any way I posted my first attempt at a video with the Mavic yesterday in Drone Discussions, [First Video With my Mavic 2 Pro].

Let’s see where this new journey may take me.


Hi Leigh, welcome to GADC , hope you find lots of interesting things on the site , its a great place with loads of friendly advise. Congratulations on passing the PFCO . Loved your video , I would just say I’ve seen some horror stories on here about flying to low over water where people’s drones just land but as I said its just what I’ve read on here so thought I should mention it . Anyway have fun and keep the videos coming.

Thanks Scotty

I have heard somewhere about drones trying to land on water too but being new I decided to be stupidly brave.

I figured as long as I went into the flight with a full battery and left plenty in there when I finished I should be ok. Had plenty of sat locks so put it out of my mind and trusted the kit. I have to say it hovered really well over water and didn’t move for me.


I think it’s more to do with the downward sensors , if I where you I would search on here as I’ve read a couple of posts where drones just land , one poor guy was on his first flight with his new I think it was a mavic 2 pro , yours might well be fine but I would search it just in case , I remember it’s nothing to do with battery , signal or sats it’s a sensor thing when near to water. Just saying as would hate to see anyone loose theirs.


Thanks again Scotty

I will certainly read up on that

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Welcome, congrats and good luck!

Yeah, I’ve seen something about that too… From what I can remember, the IMU (downwards sensor) gets upset when flying over surfaces with very little pattern/contrast e.g. still water, and then has a fight with GPS, wins the fight, and takes your bird down.

Something like that… Don’t quote me :slight_smile:

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Hi there.

Hi Leigh. Welcome to GADC!
Where abouts are you in the UK?

Hey Ptero

Im based in Herefordshire

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Close… you’re on the right track :slight_smile:

The IMU (inertial measurement unit) looks after the stability of your drone in the air, while the VPS (vision positioning system) looks after what’s going on underneath you when you’re at low altitudes or coming in to land.

It’s that VPS, as you rightly eluded to, which can get confused over water and other weird looking / repetitive surfaces. Which is also why sometimes the precision landing can be a little bit off when landing on grass and also why hovering at low altitudes might not keep your drone that steady as the VPS can’t get a lock on something decent in order to provide the right flight corrections.

Turn VPS off when flying low over these types of surfaces :+1:t2:

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So I have watched a few YouTube opinions on this IMU “on or off” debate and it seems that opinions are finely balanced.

It seems that it depends a lot on how close you are to the water because “ground effect” (I know water) also comes into play when the drone is trying to figure out what to do.

On balance reports suggest that most drones tended to go up but thought they were at the same height on the controller display and one drone moved sideways as the waves drew back down a beach it was hovering over. One or two did go down but could be corrected out of that situation.

I cant find any good reports of the drone announcing it was “landing” though so will keep searching.

I guess the point is don’t fly over water unless you have to and then keep a very close eye on the drone not your controller so you can quickly feed in a thumb load of correction.

VPS? :blush:

Indeed, the VPS will only play a part if below X height.

You’ll be perfectly fine flying (low) over water if you turn off the VPS :slight_smile:

With a DJI craft I’m not sure any amount of left-stick-up will override an automated landing sequence, will it? :thinking:

If low battery is set to land, you can intervene … but not for long. You can actually go up … briefly. (Well - on the MP, at least, with whichever firmware version I’m on. :man_shrugging:) So I can’t imagine the auto land is that different in this “over water” instance, either.

But - then again - all my sensors are always off these days, in any case.

Do you need to press the Pause button on the MP controller first? And then it lets you take manual control?

I’m not sure I’ve ever tried this…

:thinking: I can’t think that I would have bothered with pause.

One for my list of things to specifically test. (The low battery - not the landing on water!)

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