Not a noob, Had a malfunction, Need advise please

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As I motioned in the title I'm not a noob. Do everything by the books every flight. Never seen this with my two Phantom 2's or Phantom 3 Pro until tonight.

Normal take off, with 17 sats, all green, with 4 mph wind...and within about 350-450 feet my P3 starts "wondering about." Phantom just started spinning in semi-tight yawing circles with ZERO stick input. When I notice it's random movement on my iPad screen I made quick movements with the sticks (yawing) to see if the P3 was receiving my input. It was BUT it kept spinning maintaining current altitude for the most part. Immediately switched to Atti mode and regained control. Brought it in closer, flipped back to P-GPS and all was normal so I landed right away.

What the devil happened? I powered down, powered up, took off and tested again....twice. No issues.

• 174 P3P flights with zero issues
• Latest firmware install since the day it was released
• Did a cold IMU calibration last night since I hadn't done one in about 3 weeks. Did it in the same spot as before. No issues. Mod reading was at 1500 when complete.
• Did a successful compass calibration right before the flight (Mod reading was at 1520-ish right before flight)
• No power lines around. (I've taken off and tested from this home point site 70-80 flights at least with the P3P.)

I checked the fight within the Pilot App to confirm my stick movement and more importantly my LACK of stick movement while it did it's little walk about in the air. Pict attached with notes...

Any advise would be warmly welcomed.

Image-1.jpg
 
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Based on DJI forum, if you recalibrate IMU after update - you will have issues, if you do not you will not.
 
I'd dig for gold in them there hills if I was you...it's an obvious sign.

But seriously, interesting. I'll follow to see what others have to say.

At what height were you flying when it happened?
 
I'd dig for gold in them there hills if I was you...it's an obvious sign.

But seriously, interesting. I'll follow to see what others have to say.

At what height were you flying when it happened?

Just checked the flight record. At about 118 feet.
 
It appears, to me, once you flew past those trees below waypoint 1 your aircraft starts to lose control. It isn't until you return to waypoint 5 where you did your atti-gps switch-over and gps started working. I'm leaning towards the gps malfunctioning.. I see the trees are missing there as if they have been cut down. Perhaps they are building something there, something underground? The map we see, is it up to date, or has some sort of development taken place? Or maybe it was a very heavy cloud? Have you tried flying at the exact same spot again?
 
It appears, to me, once you flew past those trees below waypoint 1 your aircraft starts to lose control. It isn't until you return to waypoint 5 where you did your atti-gps switch-over and gps started working. I'm leaning towards the gps malfunctioning.. I see the trees are missing there as if they have been cut down. Perhaps they are building something there, something underground? The map we see, is it up to date, or has some sort of development taken place? Or maybe it was a very heavy cloud? Have you tried flying at the exact same spot again?

Thanks for the reply.

This is an old satellite map photo. The tree line is full and lush. The construction there are finished houses now. It's my backyard. So with two P2's and a P3P I've probably taken of from the exact spot hundreds of times with not one issue. Tried two more very low and close tests after this... no problems at all. GPS worked fine, craft hovered and stopped on a dime. Nutty. And makes me nuts! I'm just glad it was so close and I maintain a LOS. Switching to ATTI stopped the "issue" but it took a few seconds of moving sticks for me to visually orient myself to know which way I was facing. Tonight I learned seconds can be precious!
 
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Did the gimbal horizon go bad at the same time it started circling? Loss of control and circling is usually TBE. Switching to ATTI removes the compass and GPS which is where the conflict lies.

Most likely bad compass calibration and/or magnetized take-off point.
 
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Did you figure anything out? I had my third tonight and just after my P3P took off, I was hovering around 10ft and it just started drifting one direction to another. Mine was in P-gps mode with 15 satellites and a safe to fly gps notification at the top of my screen. I was constantly countering its actions so I just landed it. I have a very powerful wireless network but it hasn't interfered thus far but I immediately cut off the 2.4ghz side of the network and power cycled the P3 and it worked fine. 2.4 ghz wifi actually has 11 channels (1-11) and with the P3 only having 8, I'm thinking there was interference due to frequency overlap on the channel the P3 selected during initialization. Needless to say I was freakin nervous during my next flight but all went well.
 
Btw, latest firmware uploaded, compass and IMU were calibrated. Now my remote will not charge all the way. It will flash like it's charging for about an hour and it just stops charging. Only two full lights and a partial third light indicated.
 
Like a motioned in the title I'm not a noob. Do everything by the books every flight. Never seen this with my two Phantom 2's or Phantom 3 Pro until tonight.

Normal take off, with 17 sats, all green, with 4 mph wind...and within about 350-450 feet my P3 starts "wondering about." Phantom just started spinning in semi-tight yawing circles with ZERO stick input. When I notice it's random movement on my iPad screen I made quick movements with the sticks (yawing) to see if the P3 was receiving my input. It was BUT it kept spinning maintaining current altitude for the most part. Immediately switched to Atti mode and regained control. Brought it in closer, flipped back to P-GPS and all was normal so I landed right away.

What the devil happened? I powered down, powered up, took off and tested again....twice. No issues.

• 174 P3P flights with zero issues
• Latest firmware install since the day it was released
• Did a cold IMU calibration last night since I hadn't done one in about 3 weeks. Did it in the same spot as before. No issues. Mod reading was at 1500 when complete.
• Did a successful compass calibration right before the flight (Mod reading was at 1520-ish right before flight)
• No power lines around. (I've taken off and tested from this home point site 70-80 flights at least with the P3P.)

I checked the fight within the Pilot App to confirm my stick movement and more importantly my LACK of stick movement while it did it's little walk about in the air. Pict attached with notes...

Any advise would be warmly welcomed.

View attachment 24526

There was very strong electromagnetic activity yesterday. I had my bird move on its own last night. I checked my app and it indicated K7, but I took off any way just to see if I would notice an effect on flight control. So, for now on if the app is K5 or above the bird is grounded.
 
There was very strong electromagnetic activity yesterday. I had my bird move on its own last night. I checked my app and it indicated K7, but I took off any way just to see if I would notice an effect on flight control. So, for now on if the app is K5 or above the bird is grounded.
In my opinion, that can do it.
 
Was your gimbal issue resolved? (thinking to the weight of the filters you installed)
 
There was very strong electromagnetic activity yesterday. I had my bird move on its own last night. I checked my app and it indicated K7, but I took off any way just to see if I would notice an effect on flight control. So, for now on if the app is K5 or above the bird is grounded.
Whatever this was caused by, it had nothing to do with solar flare activity.
If space weather influences were high enough to have any effect, it would only make the Phantom's GPS position slightly inaccurate. It would not make a Phantom fly off anywhere, do circles or anything else the pilot hasn't input.
 
I've kept reading on some forums here, about phantoms erratic behaviours with no bad consequences. But reading your post here...I can say you are the 4th pilot that has had similar situation. The common denominator in these 4 cases (that I've read so far) is that pilot was over houses and at relative height of 100-200' alt or so. I'm no expert in electronics, but could it be the houses and appliances. So many wifi's...microwaves...remote control...other remote control vehicles...etc.

It's just a thought. Nothing substantiated.

Calm winds and good flying to you!
 
Did the gimbal horizon go bad at the same time it started circling? Loss of control and circling is usually TBE. Switching to ATTI removes the compass and GPS which is where the conflict lies.

Most likely bad compass calibration and/or magnetized take-off point.

Yes the gimbal went out of whack at the same time. I'll try a fresh cold IMU calibration, compass calibration and a new pair of shorts.

Thanks for all for your responses. I really appreciate it. I'll post an update.
 

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