Height stability over water

[tcope]

DJI says it in the manual. Note the AND below. But we all know that DJI manuals are sometimes vague/inaccurate.
I haven't tested with the M2P having these sensors switched on since over water I always switch downward sensors off due to my experience with the P4P:
It tends to get sucked down over water with its ultrasonic sensors being on.

View attachment 48489

I reread your post and did not read it correctly before. It helps _positioning_ with no GPS but still, it does not change altitude.

 

[tcope]

As far as I know the Mavics use GPS for normal height data outside of some specific flight modes so it shouldn't matter much what you're flying over as long as you follow best practice for GPS (12 satellites or more before take off).

It does not use GPS for altitude, it uses it's barometer.

 

[Turn11]

The operative words are MAY NOT not will.

 

[CanadaDrone]

It does not use GPS for altitude, it uses it's barometer.

Yes my mistake, I mis-typed thinking of drift - no coffee today Thanks for the correction.

 

[DanMan32]

M2 doesn't have terrain mode.
Vision sensors would have to play a part. Note in your telemetry that it shows VPS height when you're close to the ground.
I also flew in normal P node close to the ground along my lawn which has a gentle slope. The AC rose up the slope, not getting any closer than 1.6' VPS from the lawn. The H indicated a negative value, which was an accuracy drift since I launched from the lowest point in my driveway.

 

[Chopstix Kid]

I calmed my nerves about losing my M2P in my lake and being unable to then file a claim by using the flotation skids from iRepairMD.

Huh? What I miss?

 

[LakeTravis]

I calmed my nerves about losing my M2P in my lake and being unable to then file a claim by using the flotation skids from iRepairMD.

I live on a large lake and frequently fly over water, My iRepairMD skids are on their way--I'm looking forward to their arrival. I had a homebrew set made out of fun noodles that I frequently used on my original Mavic Pro. The bright orange increased LOS quite a bit, as well,

 

[tcope]

M2 doesn't have terrain mode.
Vision sensors would have to play a part. Note in your telemetry that it shows VPS height when you're close to the ground.
I also flew in normal P node close to the ground along my lawn which has a gentle slope. The AC rose up the slope, not getting any closer than 1.6' VPS from the lawn. The H indicated a negative value, which was an accuracy drift since I launched from the lowest point in my driveway.

This will work as you go very slow. The affect is from the forward sensors, not the downward sensors. Speed up and you will get a collision warning.

 

[Turn11]

Speed up and you will get a collision warning.

In an open area I would run it up to flank speed and watch what happens when. Better to know now than when the rubber meet the road for the first time.

 

[GeraldV]

Don't let people scare you.
DJI drones are perfectly over water. Read the post of 'CanadaDrone' above.
I have done more than 1200km with my P4P and 85km with the M2P by now, approx. 25% over water.
And sometimes as low as 1ft. The latter one only over calm water and at low speed obviously.

The following I recorded at approx. 6ft above the water line with the MP2.
Main Rule for me: NEVER have downward vision sensors on being low over water.

Now a bit confused but will try to get those skis for safety.

Btw where did you take this shot? That cruise ship docks close to my house every couple of weeks or so. Can see it from my apartment in the harbour. ,=)

 

[MaxHam]

Now a bit confused but will try to get those skis for safety.

Btw where did you take this shot? That cruise ship docks close to my house every couple of weeks or so. Can see it from my apartment in the harbour. ,=)

That's funny. I shot this in Hamburg, Germany.

 

[Elton Hammonds]

The Android app named Marine Radar is how I track ships.

 

[GeraldV]

That's funny. I shot this in Hamburg, Germany.

Well I can tell you it comes over to Matosinhos close to Porto in Portugal often. :=)

 

[MaxHam]

Well I can tell you it comes over to Matosinhos close to Porto in Portugal often. :=)

That is amazing! I was in Matosinhos in July 2015.
We shot a Mercedes commercial at the new cruise terminal just weeks before official opening.

Still dreaming of the fish restaurants on Rua Herois de Franca. We went there every day

 

[GeraldV]

That is amazing! I was in Matosinhos in July 2015.
We shot a Mercedes commercial at the new cruise terminal just weeks before official opening.

Still dreaming of the fish restaurants on Rua Herois de Franca. We went there every day

Yeah you are spoilt for choice around here for the fish restaurants; glad you enjoyed your stay!

 

[Elton Hammonds]

Good to hear. Have fired them an email asking if they can ship to Europe. Worth it for the piece of mind.

Let me know if you would like me to assist you in any way. I'm just an old military officer with too much free time. LOL

 

[GeraldV]

Let me know if you would like me to assist you in any way. I'm just an old military officer with too much free time. LOL

Many thanks Elton and appreciate the offer of help. They replied to me and will ship to Portugal; total price of around 120$. Its really tempting...

 

[Rastus]

Main Rule for me: NEVER have downward vision sensors on being low over water.

This means you turn the downward vision sensors off before you fly over water correct? How do you turn them off?
Thanks

 

[DanMan32]

This will work as you go very slow. The affect is from the forward sensors, not the downward sensors. Speed up and you will get a collision warning.

I'd agree if APAS is on, but with APAS off, the Mavic will stop on obstacle, not avoid it. It took me a while to understand the point of APAS until I understood the difference.

Side note and observation: although VPS/clearance was accurate at low altitudes, height which is based on barometer would quickly drift negative. It's possible air pressure was going down but I suspect it wasn't.

 

[Goof]

This means you turn the downward vision sensors off before you fly over water correct? How do you turn them off?
Thanks

There's a toggle in the Go app settings, in the top tab somewhere I think.