What should I do next?

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This is probably a lot longer then it needs to be, but I really want to tell you about my situation and look for suggestions as to my next step to take.

Go my P3P in early December of last year. Did my first 3 flights on December 15th. Everything went very well and I got some really good pictures of the neighborhood.
Weather really got nasty and did not really have a good chance to fly until early afternoon on January 12th, 2016. Nice bright sunshine, no wind to speak of could hardly wait to take it for a bit of a flight. I set up the drone in the house, was about 15 degrees outside, everything looked really good. Did not do compass calibration as I was going to fly it in the front yard, same as where the first flights were made. I carried it out to the yard, just about the same place where I did the first flights. Placed it on the ground, everything looks great on the DJI GO app. Had a bunch of satellites, made sure the switch was in the P position, all ready to go.

I pulled both of the controls to the start position, and all heck broke loose! The P3P hopped about a foot into the air, came down and started cutting weeds with the props! It took me a few seconds to pull back on the Left Joy Stick, and kill the motors. Result, 1 prop with about 2 inches missing from one end, another with a long split in one side. Took it back in the house and checked it over carefully. Needed to be cleaned up a bit so did that first very carefully. In looking carefully at the 4 arms, I can see find lines in the plastic, radiating from the motor mounting screws in all directions. Some worse than others. Don't remember seeing them before, but guess I really never looked either. At this point in time, I decided to simply put it in the box, and walk away from it for the time being. Very disgusting, seeing my investment very quickly being destroyed.

Well, a week has gone by and I decided that I would set it up on the counter, check all the calibration, and put on some new props and take it up for a test spin. I fired it up on the kitchen counter, as I had done many times in the past, everything looked good. Next I went to Advanced Settings and "Reset All Settings" so I would have a clean slate, so to speak. Everything looked good, and I made sure it was in Beginners Mode. Said safe to fly (GPS) on the screen So one more test, without the props on, pull the two controls down to the start position. Out of the speaker comes, "Home Point Updated", followed by "Takeoff". On the screen were three green banners. On the bottom, "Home Point Recorded", next above "Motors Started" and above that "Return to Home Altitude 98'. Something is very wrong, and is probably what caused my problem with my last attempt at flying the P3P.

All of that seemed very strange, and I don't remember ever seeing and hearing all of that before now.
So not knowing what to do next, I decided to do the compass calibration, as it was the only thing that was not done, as if yet. Took the P3P to the front yard held it at arms length, pointing away from me and did the circle. Green lights! Great so far. At arms length pointed it down and did the circle. After going around once, I got 2 red lights! On the controller it said "Compass Error - Electromagnetic Interference." I did not have my cell phone, nothing magnetic in my pockets, must be I did something incorrect! So kept trying to do Compass Calibration in several other places in the front year, well away from everything! Every time the same failure!

I am at the end of my whits, at the moment, that is why I came here to seek advice as to my next step.

And one last piece of information, since my first and last successful flights, I have updated the P3P from 1.4 to 1.5 and then 1.6.4 The DJI GO app is now at 2.5. I am now wondering if all of the updates have led to the problem, as this is the first bad flight since doing all the updates.

Looking for advice, as I am completely lost, at this point.
Thanks,
GR
 
Last edited:
Forgot to mention, I did load my Flight Logs to HealthDrones.com, if that would be of any help finding out what is going on. I don't know how to give access to them, but there must be a way.
GR
 
The first post stating you got it ready inside is that where you turned on the battery then walked outside
 
Well I would suggest you contact DJI and see if they will cover the shell cracks as there was a known issue there. How are the compass readings in the go app? Are you on the latest version of the go app? How about the firmware version (tells you in the go app).

Healthy drones requires a file you can retrieve from your device.

 
Seeing as you reset everything, I would highly suggest a cold IMU calibration, then a compass calibration.
There's any number of things that might cause the compass calibration to fail, it's hard to speculate from here.
Next thing I would try is a completely different area, to rule out something in your front yard being the culprit.
(remember, just because you don't see it, doesn't mean it's not there.)
 
Everything looked good, and I made sure it was in Beginners Mode. Said safe to fly (GPS) on the screen So one more test, without the props on, pull the two controls down to the start position. Out of the speaker comes, "Home Point Updated", followed by "Takeoff". On the screen were three green banners. On the bottom, "Home Point Recorded", next above "Motors Started" and above that "Return to Home Altitude 98'.

All of that seemed very strange, and I don't remember ever seeing and hearing all of that before now.
So not knowing what to do next, I decided to do the compass calibration, as it was the only thing that was not done

as far as this description above that is perfectly normal and proper. at least that is what my p3 does on startup
Once you started motors, the home point is recorded and set, thus takeoff is ready. your RTH is set 98"... all OK.

anything else like cracks in shell do as suggested for replacement!

good luck and have fun flying!
 
I don't know George if you are using a USB 3.0 cable or perhaps you changed to one prior to these flights or attempted flights - I am not convinced the USB 3.0 cable and connectors can be ruled out as to a source with regard to EMI's when calibrating a compass. Further to that anytime there is any EMI present it will interfere with the signal the UAV receives via the radio controller. i.e.., the further away the UAV flies anyway, the weaker the signal gets under normal circumstances - compound that with EMI at or near the radio controller, there is a greater chance of loosing contact with your bird!. Same thing would apply one would think during calibration (EMI).

The USB 3.0 cable does emit a 2.4ghz frequency that can create EMI interference with any radio device using same frequency. The "noise" generated via the USB 3.0 can have a negative effect on the receiver if the antennae is close to the cable and/or its connector.

In order for a wireless radio receiver to detect the received signal correctly, the received signal power must be greater than the sensitivity of the radio. Hence if the "signal to noise ratio" (snr) is depleted or compromised the sensitivity limit of the receiver can be negatively influenced.

Can't say for sure that may have influenced your calibration process or not George since I am in no way any kind of technical guy when it comes to these units - I have seen the negative effect of EMI's in my line of work and read enough about USB 3.0 cables and connectors (due to other issues using these) to offer an opinion only.

I am new to this great hobby with flying and controlling UAV's - in particular my new P3A. Any information I read or posts etc. that relate to EMI's always catches my attention. I don't profess to be any kind of technical specialist but I am familiar with EMI as related to the field of work I do with regard to vibration analysis and the effect EMI can have on my spectral plots when working with unshielded accelerometers or velometers (shield to limit EMI). Unfortunately we can't shied the radio controller or the UAV from this or we would be depleting our own signal that is required!

Best of luck finding a resolve - the process of "root cause failure analysis" (RCFA) is the best way to start with regard to finding a resolve - simply replacing the Phantom without knowing the cause and effect resolves nothing.
 
One more thing here George - (I read this somewhere else) - It is important the radio controller is powered on first then your UAV!

There are reasons for this process - if your UAV is powered up first it will look immediately for the radio controller signal and if it can't find it, will try to lock onto another transmitter at the 2.4ghz frequency and as such it may not link properly or at all to your RC for that good "digital handshake" required for communication while calibrating process is taking place.

I'm pretty sure you are likely aware of this but worth mentioning I thought anyway.
 
The first post stating you got it ready inside is that where you turned on the battery then walked outside
I did the normal sequential setup, controller, then tablet, then the bird. All inside, everything looked good and was all connected. Then carried the controller, around my neck with a lanyard, and the bird out to the front yard. I backed off about 20 feet and did the start motor command with the 2 control sticks.
 
Seeing as you reset everything, I would highly suggest a cold IMU calibration, then a compass calibration.
There's any number of things that might cause the compass calibration to fail, it's hard to speculate from here.
Next thing I would try is a completely different area, to rule out something in your front yard being the culprit.
(remember, just because you don't see it, doesn't mean it's not there.)
I did load my logs to the site and look at them.
Thanks,
GR
 
Seeing as you reset everything, I would highly suggest a cold IMU calibration, then a compass calibration.
There's any number of things that might cause the compass calibration to fail, it's hard to speculate from here.
Next thing I would try is a completely different area, to rule out something in your front yard being the culprit.
(remember, just because you don't see it, doesn't mean it's not there.)
 
I live out in the country, wide open spaces, power lines a long way away, and my first three successful flights were done from the front yard. The IMU calibration was OK, but I did not do the compass for this fatal flight as I had flown the bird from the location several times without any problems.
I did walk about 200 feet away from everything, out into a last years corn field, still had the compass calibration fail, always WITH THE BIRD POINTING DOWN AND BEING TURNED IN A CIRCLE!
That is telling me something, I just don't have a clue as to what, but that is always where I get the "Electromagnetic Interference" error and the two lights go RED!
Thanks for your comments,
GR
 
as far as this description above that is perfectly normal and proper. at least that is what my p3 does on startup
Once you started motors, the home point is recorded and set, thus takeoff is ready. your RTH is set 98"... all OK.

anything else like cracks in shell do as suggested for replacement!

good luck and have fun flying!
I don't remember it saying "Takeoff" when starting the motors, but may not have heard it in my first flights, due to the excitement of the first flights on that particular day.
Thanks for your comments,
GR
 
I don't know George if you are using a USB 3.0 cable or perhaps you changed to one prior to these flights or attempted flights - I am not convinced the USB 3.0 cable and connectors can be ruled out as to a source with regard to EMI's when calibrating a compass. Further to that anytime there is any EMI present it will interfere with the signal the UAV receives via the radio controller. i.e.., the further away the UAV flies anyway, the weaker the signal gets under normal circumstances - compound that with EMI at or near the radio controller, there is a greater chance of loosing contact with your bird!. Same thing would apply one would think during calibration (EMI).

The USB 3.0 cable does emit a 2.4ghz frequency that can create EMI interference with any radio device using same frequency. The "noise" generated via the USB 3.0 can have a negative effect on the receiver if the antennae is close to the cable and/or its connector.

In order for a wireless radio receiver to detect the received signal correctly, the received signal power must be greater than the sensitivity of the radio. Hence if the "signal to noise ratio" (snr) is depleted or compromised the sensitivity limit of the receiver can be negatively influenced.

Can't say for sure that may have influenced your calibration process or not George since I am in no way any kind of technical guy when it comes to these units - I have seen the negative effect of EMI's in my line of work and read enough about USB 3.0 cables and connectors (due to other issues using these) to offer an opinion only.

I am new to this great hobby with flying and controlling UAV's - in particular my new P3A. Any information I read or posts etc. that relate to EMI's always catches my attention. I don't profess to be any kind of technical specialist but I am familiar with EMI as related to the field of work I do with regard to vibration analysis and the effect EMI can have on my spectral plots when working with unshielded accelerometers or velometers (shield to limit EMI). Unfortunately we can't shied the radio controller or the UAV from this or we would be depleting our own signal that is required!

Best of luck finding a resolve - the process of "root cause failure analysis" (RCFA) is the best way to start with regard to finding a resolve - simply replacing the Phantom without knowing the cause and effect resolves nothing.
I have not changed the cable since the first flight, and I did a really nice look at all the signals coming from the bird with my Spectrum Analyzer, nothing unusual at all there.
Long time Amateur Radio Operator, (WB8BGY) 45 years, very familiar with EMI and spurious signals.
Thanks for the reply,
GR
 
One more thing here George - (I read this somewhere else) - It is important the radio controller is powered on first then your UAV!

There are reasons for this process - if your UAV is powered up first it will look immediately for the radio controller signal and if it can't find it, will try to lock onto another transmitter at the 2.4ghz frequency and as such it may not link properly or at all to your RC for that good "digital handshake" required for communication while calibrating process is taking place.

I'm pretty sure you are likely aware of this but worth mentioning I thought anyway.
Everything was well connected and responding as I carried the controller and the bird out to the front yard. And I did follow the procedure for startup.
Thanks,
GR
 
I did the normal sequential setup, controller, then tablet, then the bird. All inside, everything looked good and was all connected. Then carried the controller, around my neck with a lanyard, and the bird out to the front yard. I backed off about 20 feet and did the start motor command with the 2 control sticks.
I am having a similar problem with my P3A. I get everything ready and all indications point to a go, then I take off. Shortly after takeoff, I loose connection with the app. When I reconnect the app. I get a disconnected signal and cannot reconnect until I turn everything off and reboot. When I regain signal, I get compass error and caution electromagnetic interference. I know for a fact there is no such interference as I've flown the same areas for almost a year. I can trace all my problems to my last firmware updated. I've re-calibrated, reinstalled and read about every possible cause but cannot get it to respond. One day perfect with previous firmware the next unusable. Sent a query to DJI support for answers and all they could give me was "insure you have a compatible tablet or phone".
 
My last update was 1.6 on the P3P and 2.5 on the controller, what was yours?
GR
 
I did the normal sequential setup, controller, then tablet, then the bird. All inside, everything looked good and was all connected. Then carried the controller, around my neck with a lanyard, and the bird out to the front yard. I backed off about 20 feet and did the start motor command with the 2 control sticks.

FWIW
I recommend you place the quad where you intend to launch from rather than fire it indoors and carry out.

several thing happen during warm up period,
most important are your home point and compass are set in memory.

also inside it is more likely something can introduce interference to compass or radio link.

good luck and have fun flying!
 
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I did walk about 200 feet away from everything, out into a last years corn field, still had the compass calibration fail, always WITH THE BIRD POINTING DOWN AND BEING TURNED IN A CIRCLE!
That is telling me something, I just don't have a clue as to what, but that is always where I get the "Electromagnetic Interference" error and the two lights go RED!

The above described situation alone is a good reason to contact DJI and claim the warranty repair for the compass and for subsequent damages. Good luck!

BTW, get your story organized and succinct before contacting DJI.
 

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