If you get the prompt, first try powering off the drone and moving to a different spot and then power back on. If it prompts you to calibrate again, then calibrate it yes.
Worst flight ever with p4p I'm still shaking, no control but got it landed
- Thread starter Snowwolf
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I haven't read every post in this thread. But has anybody noticed that gpsHealth is inversely proportional to the height. Would expect just the opposite. Very strange. The same is true for number of satellites.
Meta4
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Wonder why I could not keep control of the drone ? When I got it under control it then shot off doing whatever it wanted to, I remember having full forward stick just to keep it stationary, then all of a sudden it would shoot off, all very strange
Because your compass and IMU and gyro were failing. I've told you this.
No drone will fly right with those having issues.
ianwood
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OK. You had errors from the very beginning. If you see a compass error, land. If you see you GPS going to zero, land. Both of those happened almost immediately. The "J hook" you saw in previous flights is indicative of a bad compass calibration. That needs to be fixed.
Follow these steps:
Follow these steps:
- Take the tracker off. It is likely emitting a ton of RF and probably screwing up your GPS. You can put it back later if it's not the problem.
- Do a compass calibration. Yours is likely to be bad. Read this first: Compass Calibration, A Complete Primer
- If you have another drone and you know an area where it works well, do a quick flight test there. Up, down, forward, back. If you see any compass warnings or GPS errors, land. If it doesn't fly accurately, land.
It's likely that your craft was going in and out of GPS mode for control. When it took off with a mind of it's own, it was likely remembering where it was before losing GPS and wanting to go there once it got it's bearings. Had you switched to ATTI mode immediately when you saw things going bonkers, most likely you wouldn't have had as much trouble bring her back. So next time keep that in mind, but you definitely have something awry going on with your craft. Flying ATTI isn't that difficult if you practice. The altitude will still keep you level using the barometer, but you simply have to point the craft home to return. If you can't see the craft with VLOS, and you can't figure out which way home is through the FPV, you may have difficulty navigating home. If the radar screen is working, that will help you point her home, but the radar screen direction indicator might not work in some scenarios, such as compass error situations. Flying ATTI isn't difficult, but landing with wind can be difficult without tipping upon landing, and catching very dangerous so you don't want to try that. In that case find some bushes or tall grass to salvage a bad situation.
It's really odd that your GPS reception was so spontaneous. I've never seen that. I think the GPS hardware has a problem, seems like a hardware problem to me, unless you were flying around high tension wires. I've had GPS issues flying below high voltage (450KV) lines. Never had an issue flying above them though. It could be your tracker if that particular tracker is always broadcasting real time positioning, but I don't think that's the issue, IMHO. If you have a mode in the tracker that restricts positioning from being transmitted until you call the phone# of your sim, that may be an experiment to try.
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Meta4
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Switching to atti isn't the magic cure-all.
In this case the Phantom was in atti for much of the flight anyway and still hard to control because of all the other error conditions.
The whole flight record is a mess of error messages.
I agree, it doesn't fix things, it only mitigates the root problem. I was just suggesting ways to land faster and safer in this scenario. Given the data it appears the craft was getting it's bearings, and losing it's bearings, over and over, resulting in spontaneous uncontrollable flight each time it would get it's bearings. I think ATTI would have removed the spontaneous flight symptoms, but it doesn't fix the root problem of course.
DJI has him sending his drone in for repair. Which doesn't surprise me given the multitude of systems error if in his logs.
Switching to Atti is certainly not a magic cure-all but the craft was not in Atti for much of the flight : it is constantly switching between GPS and Atti.
In such case, the only and very first thing to do is to switch to Atti. If it doesn't cure, at least things wont go worse.
And it is certainly better than struggling with the sticks (for sure they wont cure anything) or pushing RTH in a hurry.
In such case, the only and very first thing to do is to switch to Atti. If it doesn't cure, at least things wont go worse.
And it is certainly better than struggling with the sticks (for sure they wont cure anything) or pushing RTH in a hurry.
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I had a similar problem with my P4P. I will be getting it delivered back from DJI tomorrow. They had to replace the GPS module.
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I looked at this flight some and will speculate there two problems.Clearly, the GPS module needs help.I'm still puzzled why the GPS is OK on the ground but starts failing with altitude.
It also appears the launch site was geomagnetically distorted as @F3honda4me was supposing.. At launch the difference between the magnetometer heading and the FC heading was about 10 degrees. During ascent the difference increased to about 35 degrees when the AC reached 3.7 meters.
It would seem that the Mavic FC is smart enough to take corrective action when this happens. Recorded flight data vs real time data The P4 Pro probably is as well. However, with the GPS problems it wasn't able to.
I couldn't find any data or reason to suspect the compass needed calibrating
It also appears the launch site was geomagnetically distorted as @F3honda4me was supposing.. At launch the difference between the magnetometer heading and the FC heading was about 10 degrees. During ascent the difference increased to about 35 degrees when the AC reached 3.7 meters.
It would seem that the Mavic FC is smart enough to take corrective action when this happens. Recorded flight data vs real time data The P4 Pro probably is as well. However, with the GPS problems it wasn't able to.
I couldn't find any data or reason to suspect the compass needed calibrating
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Hi all, hanks for replies, I have only just got home from work,
Having not had any real flying issues in the last year with the P4 or the P4P I guess you get a bit complacent and expect flights to go ok, everything looked fine on the screen as I took off and like I always do I tend to keep my eyes on the drone as I'm ascending just to make sure all is looking ok, then I usually hover and check the screen, but it did not give me any time to look at the screen after that as it went into demonic mode, I am sure at one point I did switch it to atti mode but it made no difference to what it was doing and switched back into P mode hoping it would gain its brain back and start to be normal, I'm unsure if it will tell you in the data if I did that ?
I also took the drone for a fly the next day in a different place without the tracker and it flew quite steady but still had gps problems as it was doing the crescent shape when you let go of the stick when going forwards or back, I did two compass calibration, and it still flew with the crescent shape stops, I also attached the tracker back on just to see if it was that and it flew exactly the same, steady but with crescent stops.
DJI emailed me an RMA today with a ups paid shipping, which I will send off on Friday, DJI have been very good with lots of correspondence via emails which is very good, feel very confident they will sort it out quickly, I just can't fly until it's been back to them and to be honest I hope a different one comes back.
Having not had any real flying issues in the last year with the P4 or the P4P I guess you get a bit complacent and expect flights to go ok, everything looked fine on the screen as I took off and like I always do I tend to keep my eyes on the drone as I'm ascending just to make sure all is looking ok, then I usually hover and check the screen, but it did not give me any time to look at the screen after that as it went into demonic mode, I am sure at one point I did switch it to atti mode but it made no difference to what it was doing and switched back into P mode hoping it would gain its brain back and start to be normal, I'm unsure if it will tell you in the data if I did that ?
I also took the drone for a fly the next day in a different place without the tracker and it flew quite steady but still had gps problems as it was doing the crescent shape when you let go of the stick when going forwards or back, I did two compass calibration, and it still flew with the crescent shape stops, I also attached the tracker back on just to see if it was that and it flew exactly the same, steady but with crescent stops.
DJI emailed me an RMA today with a ups paid shipping, which I will send off on Friday, DJI have been very good with lots of correspondence via emails which is very good, feel very confident they will sort it out quickly, I just can't fly until it's been back to them and to be honest I hope a different one comes back.
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This is exactly what happened to me. On the ground I'd have full sats take off with full sats. Hover and go down to 0. I'd then regain sats slower. Rock the drone left and right and lose sats and get a GPS exception. Recalibrated everything but to no avail. RMAd to DJI. They replaced the GPS module and will have it back tomorrow.
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ianwood
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As I said before, the compass calibration is way off. The "crescent shapes" are symptoms of this. Do not fly until the compass calibration is fixed. There is no way to get any reliable flight until the compass is calibrated properly.
As for the GPS drop outs, it could be a defective unit.
As for the GPS drop outs, it could be a defective unit.
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