rolling56 Posted at 2017-12-28 12:24
Here's something to throw in the mix

interesting. Not once did i see it "auto land" like people were saying would happen.

apparently this topic is highly debatable as you can read from these links below. All the pages of talk and no one has a clear answer on it.

https://mavicpilots.com/threads/ ... -about.13128/page-6

https://www.reddit.com/r/djimavi ... to_ensure_my_mavic/
One thing i know is i never had a problem over water. Whether hovering or flying feet above the surface. Looks like if anything happens it ascends (which could cause its own issues based off where you are flying)

Let's not forget the much earlier reminders that the downward positioning is also sensed VISUALLY by the downward facing cameras, not just ultrasonic sensing.  When the surface of the water is very smooth, it can sometimes see the bottom of the body of water and make judgements based on how far it thinks it is from that surface, ignoring the water surface because it doesn't see it.

AG0N-Gary Posted at 2017-12-28 12:58
Let's not forget the much earlier reminders that the downward positioning is also sensed VISUALLY by the downward facing cameras, not just ultrasonic sensing.  When the surface of the water is very smooth, it can sometimes see the bottom of the body of water and make judgements based on how far it thinks it is from that surface, ignoring the water surface because it doesn't see it.

That makes sense and also goes along with one members video flying over water and then dropping onto a shallow area and then flying back out without pilot interaction. To bad the pilot did not have line of sight to see it happen

rolling56 Posted at 2017-12-28 12:24
Here's something to throw in the mix https://www.youtube.com/watch?v=FihnvkaN83M

Well, there is real life evidence from a part 107 qualified pilot - you can fly low over water but you better be able to see the drone very clearly and be experienced enough to react in a second as the VPS is basically ineffective at that altitude over water. As I said, the risk of loss increases. I've flown over water many times but never that low and I wouldn't recommend doing so to anyone.

A CW Posted at 2017-12-28 13:53
Well, there is real life evidence from a part 107 qualified pilot - you can fly low over water but you better be able to see the drone very clearly and be experienced enough to react in a second as the VPS is basically ineffective at that altitude over water. As I said, the risk of loss increases. I've flown over water many times but never that low and I wouldn't recommend doing so to anyone.

Exactly i agree with or without sensors turned on.

rolling56 Posted at 2017-12-28 13:57
Exactly i agree with or without sensors turned on.

The drones' reaction without VPS on is a surprise but thats prob because it's controlled entirely by GPS/GLONASS and can have a variance in altitude of a few feet without VPS turned on. Yep, the bottom line here is do it at your own risk I guess. I'd rather go home with my £1200 drone in the bag than run the obviously high risk of leaving it in the drink. TBH if I want a shot that low I'll just use a hand held camera - drones are designed to be flown in the sky the last I checked rather than being used as a hovercraft.

I fly over water regularly with no issues. Wouldn’t recommend for new pilots

Woe Posted at 2017-12-28 14:07
I fly over water regularly with no issues. Wouldn’t recommend for new pilots

The debate isn't just about flying over water (no harm in that when you know what you're doing) but flying over water at very low altitudes.

Thanks for all the replies people.

So, flying 2 ft over the water level at my local lake is no bueno huh? Noted, thank you.   

It sounds like the answer here is anything below 2m traveling at 22mph could cause problems, according to A CW's post, thank you. Can I assume then, that flying over....... o lets say 30 ft, at any speed, is safe? Sports mode I hit 40 mph, does that mean double the recommendations from the 22mph? 4m = 13.1 ft, so 30 ft seems like a safe height to fly? Not many boats 30 ft high on my local lakes either, so it's safer than 5 ft off the water and potentially hitting something.

Not a newbie here, but also not experienced by any means. I just like to fly!

@Dirty Bird          You are a beast! I noted on your channel, but I thought I would mention it here. In your third video you posted in this thread, you not only fly over water like a beast. You also fly miles past bridge antennas, cruise ship antennas but you even had enough battery left to chase some kids around the park. I watched the whole thing, start to finish and my palms were sweaty cause I was nervous watching the flight. You sir, are a beast! (good thing in America, don't want to offend)

rolling56 Posted at 2017-12-28 12:24
Here's something to throw in the mix https://www.youtube.com/watch?v=FihnvkaN83M

Good one to add there. Ed Ricker does good viddies; I've prolly watched 'em all.

Bulldog Posted at 2017-12-29 07:01
Thanks for all the replies people.

So, flying 2 ft over the water level at my local lake is no bueno huh? Noted, thank you.   

The way I see it is the higher you fly and the slower you fly the more space and time you will afford yourself to react to a potential malfunction. The more experienced you become the more control you will have in flying the drone lower and faster. Your Mavic can fly 2' over the sea at 40MPH+ if you wanted it to but I wouldn't recommend it... The VPS sees the ground at altitudes of 2-13m so at around 15m AGL the VPS won't be effective anyway. Ensure you have a good GPS connection too as without VPS this is what will prevent ATTI mode. Hovering a few feet over water in ATTI mode is not a good idea - flying fast is as good as throwing your drone away. It all comes down to balancing out the risk. The main factor between water and land is that if the drone crashes into the water there is a 99% chance you'll never see it again and as I said before, most insurance providers will need evidence of the crash by producing the broken drone to tick off the potential of insurance fraud - you can't do that with your drone in a lake or beneath the waves. I fly over 50' when above water at any speed I wish. I've never lost a drone.   

Hi for my experience if you flight over the water and MP falls in the water for an HW or SW problem you’ll have no way out. My drone falls in the water because forward sensors didn’t work. DJI Europe did’n’t e pair my MP and so I bought another one!

ny300z Posted at 2017-12-28 10:25
The mavic auto lands when its within a couple feet of the ground? i never heard that or saw that happen.
As far as i know the mavic lands when very close to the ground and you HOLD the left stick down. It never autolands

It sure does, if you have Precision Landing / Landing Protection enabled, when you land manually, not talking auto land here, when it pauses to check the landing area, if you continue to hold the left stick down, it then starts to land, let go of the left stick and it will continue to land and shut off.

Up left stick will prevent this behaviour, it was updated an a previous release as originally once the landing commenced there was no way of stopping it.

Yep, that is exactly what it does!

Buzzyone Posted at 2018-1-2 07:53
It sure does, if you have Precision Landing / Landing Protection enabled, when you land manually, not talking auto land here, when it pauses to check the landing area, if you continue to hold the left stick down, it then starts to land, let go of the left stick and it will continue to land and shut off.

Up left stick will prevent this behaviour, it was updated an a previous release as originally once the landing commenced there was no way of stopping it.

I know this 100%. What i was talking about was that people in this thread were clearly saying it could just auto land on its own if the VPS or landing protection malfunctions from flying or hovering close to the water. Which it does not.

ny300z Posted at 2018-1-2 08:11
I know this 100%. What i was talking about was that people in this thread were clearly saying it could just auto land on its own if the VPS or landing protection malfunctions from flying or hovering close to the water. Which it does not.

Feet over the ocean with sensors turned off with my P3A with no issues.

https://youtube.com/watch?v=vRzP8RpunCE here the video

ny300z Posted at 2018-1-2 08:11
I know this 100%. What i was talking about was that people in this thread were clearly saying it could just auto land on its own if the VPS or landing protection malfunctions from flying or hovering close to the water. Which it does not.

What i was talking about was that people in this thread were clearly saying it could just auto land on its own if the VPS or landing protection malfunctions from flying or hovering close to the water. Which it does not.

You're correct; the Mavic does not spontaneously try to land while flying close to the surface of water or solid ground. I know that from personal experience and I've never seen any log data to suggest that others have experienced different behavior.

DroneFlying Posted at 2018-1-2 09:46
What i was talking about was that people in this thread were clearly saying it could just auto land on its own if the VPS or landing protection malfunctions from flying or hovering close to the water. Which it does not.

You're correct; the Mavic does not spontaneously try to land while flying close to the surface of water or solid ground. I know that from personal experience and I've never seen any log data to suggest that others have experienced different behavior.

Agreed, I have done flights like that over 30 times. Did one yesterday feet off the water with everything turned on.

Someone should make a drone life jacket that inflates upon getting wet.

Larry Drone Cal Posted at 2018-1-2 17:14
Someone should make a drone life jacket that inflates upon getting wet.

I've seen a few people say they use this:

GetterBack GRB Depth Activated Underwater Recovery System

So, I'm late to this party but here's my preventative 2 cents.
I do fly over water a whole bunch, usually take off from a boat, video surfing or wake boarding, and hand retrieve from the boat.  Previously did this with a P2V+, skipped a whole lot in between and got DJI Care refresh with the Spark.  My biggest issue was the chirping in my ear from my wife the whole time while flying, about how I was just going to throw $1300+ in the water with the P2V+...adding to the stress of my flights.  She would actually preemptively say nothing needed to be videoed when we went out and would pretty much discourage all flying, over land or water, for the cost.  Now, with the Spark, I really don't care to get into the brass tacks of what would be covered in the event of a water incident, but it did get my wife to shut up with the constant discouragement to fly over water especially.  The argument then was how I was going to get it back to submit for coverage.  Getter Back Rod Recovery system, I swear, it saved my persistent interest in flying with her dogged interest in stopping me.  Best $15 I ever spent...plus however much it was for the DJI Care Refresh.  There was little to no impact on the performance of the Spark with this velcroed to one of the back arms of the Spark and I hope to find that it does well on the Mavic Air.

Griffith Posted at 2017-12-28 08:35
Just beware that winds over the ocean may be different than over land.  Be prepared to switch to Sport Mode to get the bird back to terra firma.   Make sure you'r height will accommodate swells :-)

True.  I shoot over water and ocean waves all the time.  Just make sure you account for the swells coming in.  Makes for great shots flying backwards over waves.  I enjoy flying 'low' to get some great footage.  

Oh, and watch out for the birds!  

We fly our phantom 4 pro very low over the ocean. In that case I bring a spotter who warns me for swell and waves. to get the settings right, I did this test on a lake. I had to swtich VPS and landing protection off to be able to catch the bird on a small boat. When we fly your drone over the ocean and fly really low, we switch all sensors off. It is risky though.
Video of the test to get the settings right: https://youtu.be/EYtD9gQ7iYE

Griffith Posted at 2017-12-28 08:35
Just beware that winds over the ocean may be different than over land.  Be prepared to switch to Sport Mode to get the bird back to terra firma.   Make sure you'r height will accommodate swells :-)

oh so true,  birds are the worst problem!

I wish people would stop saying it will auto land while flying low over water. IT DOES NOT, you can fly low over water. RTH is a different story but I never use that anyway.

Larry Drone Cal Posted at 2018-1-2 17:14
Someone should make a drone life jacket that inflates upon getting wet.

Here's my new design to get my Mav back.  Lost one already, not due to hovering over water.  I'm going to simulate a mav(weight and shape, for buoyancy purposes) and test and film it.  I'll post it when I'm done.  I bought a few of these for testing.

Little info on "water-buoy".  It inflates upon submersion and floats 1Kg.  It also has a strobe that flashes inside the balloon for 24 hrs. which is kinda cool.  Like I typed, I'll post the test vids I will do soon!!

Bolton