One thing I have to say is that the stability of my P4 has been excellent since the day I bought it.  I had some minor issues with altitude drop, which has been corrected with the last firmware.  My only issue so far is Video transmission and Range.  As a result I have been experimenting with range extenders.

But today, I witnessed something that "shook me up":

Please see the video below, at the 1.1 minute.  It was not windy today, it was only about 4 MPH and wind gusts to 8 MPH.  I was flying about 170 feet over water, and the P4 was making a 30 degree turn to the left, while flying straight ahead, flying a WP mission.  I have never experienced this before, so I cancelled the mission and went back home.

Any ideas?


I was flying 31 MPH.  When I flew the mission backwards manually, it was smooth as you can see.
H.D. logs show no issues.  Everything is green.

No video attached.
Were you using the GO app?
Did the aircraft yaw 30° or did the direction of travel change 30°

DJI-Ken Posted at 2016-9-14 17:47
No video attached.
Were you using the GO app?
Did the aircraft yaw 30° or did the direction of trav ...

Yaw 30 degrees. I was using litchi WP.  I flew the same exact mission yesterday and it was smooth.  I will try to find the same video from yesterday, and it was 15 MPH wind yesterday.  I was just adding more distance today, but that event stopped me short!

I don't see a yaw at 1:10 but the moving I see at 1:20 is from the wind, you can even see the arm a few times in the video and the camera is still pretty level so it wasn't smooth.

It looks like there is more wind past the point you're approaching. Maybe the aircraft started buffeting from the slope currents...
...or possibly a bird, but there aren't any in the video. I know the uneasiness that follows an unknown event.
Good luck figuring it out... OVER LAND!

It's with a course lock, isn't it? Or waypoints or similar. At least seems to me like the camera is looking bit to a side - the craft is flying diagonally? Then it may be just a wind gust because this flying sems to me very tricky.
I did try course lock first time today and was experimenting with turning, backward flying, attitude changes, couple things together....and at one moment I was looking at my P4 in nearly vertical position, really like standing on one propeller...I stopped touching anything of course, craft was solid for a brief second in this absolutely awkward position until I cancelled course lock, Phantom get leveled, calmly hoovered and was looking at me like nothing has happened :-) I was flying in 10 maybe 20 m/s wind (need to get the wind measure thing), which is nearly permanently these days and I got no choice so I did experienced quite interesting things and you know what - this should not shook you, P4 can withstand much much more ;-)
You were also getting bit to an open sea, over deper - colder water, air streams up or down are perfectly natural....

Same Flight yesterday with higher wind 15 MPH max gust.

I see a slight wobble as it completes the yaw of 30° at the first waypoint, at about the same time about 1.2 min, and the right prop gets into the video.   And then again at about 2.5 min when it is yawing left and also making a U turn of 500 feet.

benjamin.tichy Posted at 2016-9-14 18:27
It's with a course lock, isn't it? Or waypoints or similar. At least seems to me like the camera is  ...

No Course Lock; just Waypoints to control the range testing I am performing, so it stays consistent between the 2 set ups I am evaluating.

It is from the wind.  Have a look at this flight of mine where I have exactly the same symptoms on my P4

MAD35 Posted at 2016-9-15 11:58
It is from the wind.  Have a look at this flight of mine where I have exactly the same symptoms on m ...

I admire your courage!  Would like to know how much battery power was left on landing....

Thanks Mate, surprisingly I still had 41% battery left.

MD_Icarus Posted at 2016-9-14 14:48
No Course Lock; just Waypoints to control the range testing I am performing, so it stays consistent ...

Aloha Icarus,

     Hairy nailed it, you were approaching a wind line.  It can easily be seen in the video coming off the point.  Also look at the tops of the wavelets as you start getting buffeted by the wind.  There are now whitecaps before you stop.  When you stop and then reverse, you reduce the wind effect that is causing the buffeting.  Look at the whitecaps as you reverse.  They go away.  There were some really strong gusts buffeting your P4 because you were still over a hundred yards away from the wind line.  Look at the wave directions.  One set is coming abeam from starboard and the other is almost coming straight at you but you are yawed to port.

     It appears that the hot air you were flying in was heated by the land to your port and possibly being blown from your left rear.  The denser cold air that was coming in from the open ocean was being forced over the hot air you were flying in causing an inversion.  The inversion was creating the wind line.  At the front, where the two meet, the turbulence was severe enough to create whitecaps and buffet your P4.

     Your P4 was all shook up, but no need for you to be all shook up because it was natural not mechanical.

Aloha and Drone On!

MAD35 Posted at 2016-9-15 05:58
It is from the wind.  Have a look at this flight of mine where I have exactly the same symptoms on m ...

I feel better now after seeing the same behavior and you had no issues later on.

BTW: How low were you flying back?  That looked too close to the water!!  I guess if there are waves, the sensors should not get confused. But the seaguls may get confused and some may think it is a mate in heat!

Cetaman Posted at 2016-9-15 08:46
Aloha Icarus,

     Hairy nailed it, you were approaching a wind line.  It can easily be seen in t ...

Thanks for the detailed analysis!  I am going to change course slightly as I increase my test range slowly....I chose the route because my last 1 mile is over soft terrain!

MD_Icarus Posted at 2016-9-15 04:47
Thanks for the detailed analysis!  I am going to change course slightly as I increase my test range ...

Aloha Icarus,

     You are welcome!  Soft is always good!

Aloha and Drone On!

Thanks for the feedback,

You helped me regain my confidence to go on with my range tests!

I did my 2 mile test with no issues today. Smooth as Silk...... 100% 100% only minor video streaming issues....

Definitely wind! The little motors on the Phantom 4 cameras just aren't gained highly enough to handle excess wind or hard banks in sport mode.

Tuning gimbal motors is a tradeoff and balancing act (a really delicate one) - if you over gain the motors it causes vibration, which causes jello. The gimbal holds solid, but jello is jello. If you under gain the motors too far, the gimbal has stability issues all the time, never mind in high winds. DJI chose the motors and tuning they pre-configured on the P4 gimbal to handle most situations but the motors are just too small for the kind of forces the P4 can put out at high speed. Not much can be done - bigger motors would cut the flight time and make the aircraft larger and the whole point of the P4 is to be a small copter you can fly anywhere.

It's not a "problem" per se - just the trade off of such a small gimbal on such a fast aircraft. DJI has done a really really good job with these little gimbals in my opinion (I've spent hours hand tuning Alexmos gimbals for custom camera loads and it's not even a little bit fun).

So you can probably relax and know your P4 is all good.

FWIW this has been an issue with the little Zenmuse gimbals going back to the H3-2D (GoPro). This video is my Phantom 1 and the Gimbal taking a wild power nap mid flight. You better believe the first time it happened (I was wearing FatShark goggles) it scared the crap out of me because you assume the copter is upside down rather than the camera.

SimplePanda Posted at 2016-9-15 21:37
Definitely wind! The little motors on the Phantom 4 cameras just aren't gained highly enough to hand ...

I have been enjoying smooth video so far, and I have flown with 25 MPH winds before; so the first time it gets bumpy like that it can be scary, especially if it's flying 170 feet over the ocean!  Your experience was more extreme.

Great video, great location, your shakes are a mystery .  If I had been flying, that would have been the time I dropped my beverage and tried to chatch it. All kidding around, glade you got her home safe.

Well, the wife liked the 2 mi test video so much, she made a short video clip out of it!

Where is this, by the way?

SimplePanda Posted at 2016-9-15 22:54
Where is this, by the way?

Long Island NY.