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Phantom 4 PRO blew away suddenly & quickly. Feel lucky to have it
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Rob8888
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Hi
This afternoon while flying in a moderate breeze, my P4P just started climbing and flying away very quickly down wind.

Was flying shielded flight and staying under about 40ft (it's in a ATC area and must be flown lower than the highest point within 100m).  Suddenly at about 7mins 30s the P4P just started climbing and disappeared from sight very quickly down the wind stream.  

All I can conclude is that it was similar to as if it had switched to Atti mode.  But I was in P and hadn't touched the setting.  Any right stick input seemed relative to the the airspeed, not ground, hence continuing to loose it in the wind (obviously it had no GPS guidance?).  It therefore felt like a runaway.  It was too far away to be able to see any control input and very hard to gleam info from the camera. Then lost sight of it.

So, I used RTH and crossed fingers and a while later we heard it approaching over houses.

The only unusual aspect was that I caught the P4P, brought it down to idle, and then flew it off again, but this was some time earlier. I calibrated compass prior to flight too.

Makes me very nervous about a repeat.  It doesn't take long for it to go. Gave me a good fright.  What's happening with this P4P model, seems a few similar stories happening already?

Here's the flight record: http://www.phantomhelp.com/LogViewer/YNF1VGNMUZ9QU67DFWW5/#
2017-1-1
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Rob8888
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AlecW Posted at 2017-1-1 21:18
Wind caught you is my guess.  It's way more windy the higher you go up.

Nope, definitely not. I've been flying for the last few days in the mountains here on very windy days finding a limit.  This is not wind related (though wind did make it disappear faster).  It would not hold, and the wind speed was probably less than 25% of aircraft speed anyway.
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perryb
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Rob8888 Posted at 2017-1-1 21:22
Nope, definitely not. I've been flying for the last few days in the mountains here on very windy days finding a limit.  This is not wind related (though wind did make it disappear faster).  It would not hold, and the wind speed was probably less than 25% of aircraft speed anyway.

Something is very wrong with the P4P .
2017-1-1
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CCrew
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You do realize that if you're concerned about the location you're flying in that you had your RTH height set at 80 meters, i.e.: 262 feet correct? Part of your altitude climb was actually as a result of your hitting RTH. Your flight was low, but any loss in communication would have resulted in a rapid ascent to 80 meters. You did get GPS errors a bit more than 5 minutes into the flight.

Based on home point info and distance to home in those logs, you appear to have been doing an almost vertically overhead flight?
2017-1-1
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Labroides
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This is an interesting flight record.
I can't see a simple obvious cause but what I observed might be a good starting point for someone that wants to look further.

I note an error message at 5:25 that says GPS Position No Match.
I've not encountered this before and am not sure what it means but it didn't re-occur and doesn't appear to be related to anything in the flight.
Your Phantom had full GPS for the flight but I not some horizontal drifting toward the end of the flight.

You described the incident as:
Suddenly at about 7mins 30s the P4P just started climbing and disappeared from sight very quickly down the wind stream.

Looking at the flight data and matching your stick inputs to what the Phantom was doing, it appears that the Phantom only climbed when you pushed the left stick forward.

This is complicated so I'll start with vertical movement only.
Your Phantom was hovering almost overhead at 40 feet
The flight record shows the throttle being pushed forward from 7:28.8 till 7:36.2 taking the Phantom up to 61 feet but hardly changing horizontal position.
More climbing from 7:38.1 to 7:44 takes the Phantom up to 90 feet, still almost overhead.
The Phantom hovers there until the throttle is pushed forward again at 7:54.8 - 7:57.3 and the Phantom again hovers at 110 ft
More throttle at 8:15.4 takes it to 200 feet.

I can't see anywhere where the Phantom suddenly starts climbing on its own.
All the climbing is accounted for with the controller stick input.

Now to look at the horizontal movement:
From 7:48.4 the Phantom shows slow horizontal motion with no stick input taking it about 30 feet away
At 7:53.6 the right stick is pulled back for 1 sec slowing the Phantom a little.
The sticks are released and the Phantom's speed increases to 12-13 metres/sec
At 7:59.7 a 2 sec burst on the right stick increases the speed to 15 m/s
Sticks are released again from 8:02.2 and the Phantom slows to 4.1 m/s at 8:06.7 when the right stick is again pulled back for 2 secs pushing the speed up to 7.4 m/s which slows again when the sticks are released.

At 8:10.7 the right stick is pushed hard forward pushing the speed up to 10.9 m/s when the sticks are released and the speed slows to zero at 8:20.
The Phantom slowly drifts 15 feet further without any stick input to 393 feet from home.
RTH is activated bringing the Phantom home successfully.
Successful RTH strongly suggests there is no problem with the GPS or other flight systems.

There is some unaccounted horizontal drifting that puzzles me.
There is no stick input that would have moved the Phantom left or right during this time but the Phantom's path is a series of curves rather than the generally straight line that would be expected if wind was the cause.
I'm also wondering about the stick input I see with some being forward and some is pulling the stick back.
Only guessing but wondering if there may be some disorientation?

There is also some rudder control applied at 7:28, 8:15 and 8:19 but I don't have enough information to see what this was doing.

I have to wonder about the compass being calibrated before the flight.
Why was it calibrated and where?
The manual says to only calibrate the compass if the app prompts you to.
The flight originated at the front of a house, was it on or close to reinforced concrete?


2017-1-1
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Rob8888
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Hi Labroides
Thanks for that in depth look.  
-The vertical gains would likely be me trying to retain a line of sight as it went past the adjacent roof tops as its downwind trajectory continued.  
-Taking hands off the sticks didn't stop the horizontal movement, and hold it as per normal, and the right stick movements were me trying to get a visual to orient movement and then fly it back, but by then it was too far away to discern, and I used RTH.

Interestingly the horizontal speeds leading up to the event had been around 0-2mph, then suddenly at 7:48 the speed rapidly climbs to 7+mph (which would be consistent with windspeed) with no stick inputs and that's when it started sailing away rather than holding.

This makes me nervous now.  2 days ago I was flying up through tall forest opening (hence the 80m RTH setting still) which was contiguous similar looking terrain for 10's of kilometres, no internet coverage for maps, and a strong wind, and I couldn't see the drone easily once above me.  Clearly I'm going to have to be much more competent on straight instrument flying retrieval if this happens again?

2017-1-2
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Labroides
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Rob8888 Posted at 2017-1-2 00:46
Hi Labroides
Thanks for that in depth look.  
-The vertical gains would likely be me trying to retain a line of sight as it went past the adjacent roof tops as its downwind trajectory continued.  

Was this the only unusual incident?
Have you flown since?

RTH seemed quite normal and suggests that things were normal from then on.
If it were mine, I'd give it a few test flights in an open area to see if it was just a one-off or something else.

No internet doesn't mean no maps - it's easy to cache maps before going away.

No comment on the compass? - It may be relevant.
2017-1-2
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CineView Media
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In short, this is exactly what happened to mine two days ago when it flew away, it switched from P to ATTI without touching anything, there was a brief popup message i failed to notice as i was looking at the aircraft at that time, (thats was discovered in the replay log after) then when i looked down to compose the shot i navigated trough the camera, without realizing it was actually drifting away behind me, despite the Go app map showed that it was 100ft infront of me and above... I also had strange notifications about week gps signals, even if the sat symbol showed 16 sats and increasing, thats the short vers...
Glad to see its not only me being stupid, like certain people in here applies.
If you want more details, im happy to discuss it anytome on PM with you.
2017-1-2
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Labroides
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CineView Media Posted at 2017-1-2 01:00
In short, this is exactly what happened to mine two days ago when it flew away, it switched from P to ATTI without touching anything, there was a brief popup message i failed to notice as i was looking at the aircraft at that time, (thats was discovered in the replay log after) then when i looked down to compose the shot i navigated trough the camera, without realizing it was actually drifting away behind me, despite the Go app map showed that it was 100ft infront of me and above... I also had strange notifications about week gps signals, even if the sat symbol showed 16 sats and increasing, thats the short vers...
Glad to see its not only me being stupid, like certain people in here applies.
If you want more details, im happy to discuss it anytome on PM with you.

Thankyou CineView for your input but I've inspected both flight records and yours has nothing common with this one.
Your Phantom was drifting over 1 kilometre in atti mode.
This one only went a short distance and had full GPS at all times.
There are plenty of other differences that are quite clear in the flight data.
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CineView Media
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Labroides Posted at 2017-1-2 01:11
Thankyou CineView for your input but I've inspected both flight records and yours has nothing common with this one.
Your Phantom was drifting over 1 kilometre in atti mode.
This one only went a short distance and had full GPS at all times.

Im afraid your wrong, OP says:
"All I can conclude is that it was similar to as if it had switched to Atti mode.  But I was in P and hadn't touched the setting."

That is exactly what happened to mine, and please stop argue with me about it, cause you werent there, also youre not a Dji representative that are qualified to conclude with technical problems based on just looking at someones flight log.
Feel free to suggest and have opinions about it, based on your own personal experiences, but please stop acting like you are a representative of Dji technical department and knows everything, leave that up to the specialist, cause you are not qualified to conclude with anything, its only based on guessing and assumptions.
Thanks!
2017-1-2
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Labroides
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CineView Media Posted at 2017-1-2 01:21
Im afraid your wrong, OP says:
"All I can conclude is that it was similar to as if it had switched to Atti mode.  But I was in P and hadn't touched the setting."

Guessing and assumptions are your department hotshot.
I see you still haven't been able to refute anything in my assessment of the incident you still mistakenly call a flyaway and instead just resort to personal attacks.
It's very clear from the things you write that your understanding of Phantom operations is very limited and you are way out of your depth here.
2017-1-2
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Rob8888
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Labroides Posted at 2017-1-2 00:56
Was this the only unusual incident?
Have you flown since?

This is the only incident I've had like this and I've done over 6hrs and 62km flying in the last week or so, in some very trying conditions - over sea, lakes and surprisingly high winds. Haven't flown it since sorry. Will try tomorrow hopefully.

I just replayed the flight in the DJI Go app and the moment I just lost all hold control and it starts sailing off is dramatic and familiar. It was while I was trying to compose the only photo I took. The acceleration is totally wind related (it was moderately strong), and I'm pretty sure we're dealing with a sustained loss of GPS hold (same as switching to Atti mode in strong wind).

Regarding the compass, I've calibrated prior to 90% of flights.  I was under the impression this was good practice?

Thanks regarding maps, though many places I go are remote, unplanned and lack internet for days prior, but will bear that in mind.
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CineView Media
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Labroides Posted at 2017-1-2 01:28
Guessing and assumptions are your department hotshot.
I see you still haven't been able to refute anything in my assessment of the incident you still mistakenly call a flyaway and instead just resort to personal attacks.
It's very clear from the things you write that your understanding of Phantom operations is very limited and you are way out of your depth here.

               
2017-1-2
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Labroides
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Rob8888 Posted at 2017-1-2 01:29
This is the only incident I've had like this and I've done over 6hrs and 62km flying in the last week or so, in some very trying conditions - over sea, lakes and surprisingly high winds. Haven't flown it since sorry. Will try tomorrow hopefully.

I just replayed the flight in the DJI Go app and the moment I just lost all hold control and it starts sailing off is dramatic and familiar. It was while I was trying to compose the only photo I took. The acceleration is totally wind related (it was moderately strong), and I'm pretty sure we're dealing with a sustained loss of GPS hold (same as switching to Atti mode in strong wind).

The incident was a little puzzling because the Phantom maintained GPS the whole time and there is drifting in the record.
The Phantom normally can hold position in over 25 knot winds, more than many would guess.
If the wind was strong enough to defeat GPS position holding, you probably wouldn't have launched and RTH would have been impossible.

I wonder about the role of the compass but there isn't a definite link.
If you had calibrated on reinforced concrete or close to a car, it could be possible to get a bad calibration but I don't see the telltale slow spiralling this would cause.

Recalibrating the compass is unnecessary and a risky practice.  
For the P4pro, DJI recommend not calibrating it at all unless the app prompts you to. (top of page 57 in the manual)
2017-1-2
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Cetacean
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Rob8888 Posted at 2017-1-2 01:29
This is the only incident I've had like this and I've done over 6hrs and 62km flying in the last week or so, in some very trying conditions - over sea, lakes and surprisingly high winds. Haven't flown it since sorry. Will try tomorrow hopefully.

I just replayed the flight in the DJI Go app and the moment I just lost all hold control and it starts sailing off is dramatic and familiar. It was while I was trying to compose the only photo I took. The acceleration is totally wind related (it was moderately strong), and I'm pretty sure we're dealing with a sustained loss of GPS hold (same as switching to Atti mode in strong wind).

Aloha Rob,

     Normally, Labroides would note that regular compass calibration is not a good idea and his reasons are well founded.  It may well be that your problem is from a bad compass calibration (at least from my reading of this thread).  But, we need Labroides to give his input on that issue.

Aloha and Drone On!
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Cetacean
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Aloha Cine,

     No one is stupid as far as this Forum is concerned.  What we do when flying is very abstract and confusing.  Labroides is very good at his interpretations of flight data.  You are doing your best at trying to figure out your flight issues.  This is not easy and therefore no interpretation is stupid.  But, you need to persevere in trying to figure out what your flight issues are.  Only you can truly interpret your flight issues and it is your bird.

     If you have problems with discussion in a public forum, then have your discussions with DJI tech support in private.  The public nature of this Forum holds participants to a higher standard.  Trying to divert discussion to PMs is evasiveness demonstrating a lack of confidence in your position regarding your argument.  This is not a good thing.  

     The merit is in the information.  Do you have good information?

Aloha and Drone On!
2017-1-2
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Ange1walk
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"I calibrated compass prior to flight too."

That's why it flew away, just stay out of the Rules of "Wannabe Professional Drone Operators, aka. Calibrate everything from IMU to Compass, before every flight and you will be absolutely fine.

Since i  got my P4P, i NEVER calibrated anything and it's Steady like a Rock & when looking at the Status of IMU, Compass etc, all have green bars.
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Snowwolfwarrior
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This happened to me today,  how I got it to come back I don't know, it had a mind of its own, there was minimal wind but it was flying away so fast, at some points I was full throttle forwards just to get it to stay stationary, then all of a sudden it would it would accelerate forwards, I could not let go of the sticks, because when I did it would just go and do what it wanted, luckily I'm a very confident flyer or I would have lost it for sure
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hallmark007
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Ange1walk Posted at 2017-1-2 08:01
"I calibrated compass prior to flight too."

That's why it flew away, just stay out of the Rules of "Wannabe Professional Drone Operators, aka. Calibrate everything from IMU to Compass, before every flight and you will be absolutely fine.

Your doing exactly as it says in the manual, you will be prompted when calibration needs doing, continually calibrating compass will mean you will be risking the chances of getting bad compass calibration.
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user1c2605e346
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Op do not calibrate compass or imu as long as app instructs u too. No need i have seen way to many people get into trouble by calibrating every flight! Say for instance u calibrate over concrete, and that slab has rebar in it . It can throw your values off pretty good but because u are in green / yellow app tells you it is successful...well then u start flying and it starts acting erratic...when all along before that calibration u had a perfectly fine drone/calib.
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Makirichi
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Hi everyone,

I am new in drone department but not in RC plane hobby. First lift up of my new P4P on the rear deck for quick up/down trial only. GPS on full but the aircraft started to move away when stationary 1.2M vert. so I tried to move slowly the right joy stick to bring it back, then every direction,  but nothing happened, so I push forward left joystick to gain altitude cause drone was descending slowly, so it was working. I grab it as soon as I could to be safe enough and under props.

Before leaving my deck it was shows in app that I have to calibrate the aircraft. I did not wanted to do it because in manual it said to do it only more than 1.5 M away from magnetic source like metal, magnet, power line etc..So what should I do now the app ask me to do it? As per comment here it almost have to be done in Factory?

I'am carpenter so I guess that put the aircraft on piece of wood in field far from magnetic source and the help of a 4foot level will do the job. What you guys think?

Thank you
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Rob8888
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Labroides Posted at 2017-1-2 01:54
The incident was a little puzzling because the Phantom maintained GPS the whole time and there is drifting in the record.
The Phantom normally can hold position in over 25 knot winds, more than many would guess.
If the wind was strong enough to defeat GPS position holding, you probably wouldn't have launched and RTH would have been impossible.

Yes, was flying in a mountain pass a few days back and I'd say it was gusting up towards 25knots. Held position very well, especially as I was flying under and around high tension powerlines.

Compass calibration was in the backyard where I wouldn't have expected any concrete reinforcing, and near-ish to a wooden house. Also, I'd have thought I'd have seen something prior to the 7:48mins in the tight flying situation?

As you can see, the flying I was doing had to be confined tightly into the small section, so the sudden quick departure was completely unplanned (and then became illegal, esp with jets coming in low with wind direction).

Raining today, so a trial in the open spaces of my farm is unlikely.  You can bet I'll be doing a lot more flight training in Atti mode and instrument based navigation in case this happens again. Thanks for your assistance.

PS - so what if you did get a bad compass calibration?  Is this persistent, or does it correct between flights?  Should I recalibrate next flight, or leave?
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Labroides
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Rob8888 Posted at 2017-1-2 13:25
Yes, was flying in a mountain pass a few days back and I'd say it was gusting up towards 25knots. Held position very well, especially as I was flying under and around high tension powerlines.

Compass calibration was in the backyard where I wouldn't have expected any concrete reinforcing, and near-ish to a wooden house. Also, I'd have thought I'd have seen something prior to the 7:48mins in the tight flying situation?

"PS - so what if you did get a bad compass calibration?  Is this persistent, or does it correct between flights?  Should I recalibrate next flight, or leave?"

That depends on how bad the bad calibration is.
Often it's impossible to recalibrate in a bad area but someyimes it is possible to "successfully" calibrate in an area where the earth's normal field is distorted (close to a lot of steel).
The Phantom will be OK while it's close to the steel but has no idea how to fly a straight line once it moves further away.
Here's a classic example:
2017-1-2
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RedHotPoker
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Makirichi Posted at 2017-1-2 11:02
Hi everyone,

I am new in drone department but not in RC plane hobby. First lift up of my new P4P on the rear deck for quick up/down trial only. GPS on full but the aircraft started to move away when stationary 1.2M vert. so I tried to move slowly the right joy stick to bring it back, then every direction,  but nothing happened, so I push forward left joystick to gain altitude cause drone was descending slowly, so it was working. I grab it as soon as I could to be safe enough and under props.

It's often best to start your own separate thread, to get direct attention to your post and specific questions.


RedHotPoker
2017-1-2
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f3honda4me
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To add to what labroides has said, regarding compass on the P4P...  When the drone first powers up, it determines which direction it is facing using the compass.  (a note about that in a minute)  Once it has determined this, it then uses gyro and accelerometers to determine direction and movement moreso than the compass.  (not that it stops using compass altogether though)  It basically uses these values to help it "fly" straight, etc.  If you are near some kind of metal, or other kind of interference (power lines etc) when the drone is powered up, it will cause a bad measurement at start.  Then when the drone starts flying and gets away from this interference, it will not be able to make sense of the values it is seeing and it will not fly correctly.

The compass calibration is also equally important to not do near interference or metal etc.  The compass is not like previous drones, where you had to do a compass calibration any time you flew from a new region or area.  The compass determines the magnetic effect of the area it is flying in when it powers on, so even if your compass was calibrated in china and you fly in new york, it won't affect your compass or your flight, assuming you had a good calibration in china.  This is why in the above scenario the drone will fly normal if it starts up near interference and then fly erratic once the interference changes or goes away.

The compass calibration is used to fix issues where the calibration itself is thrown off (get a magnet too close to the drone while transporting for example).  Usually the craft can detect this and will inform you that one of the compasses is off (P4P has two compasses).  But on occasion it might be only off slightly and you'll notice your craft flies slightly sideways when you are trying to go forward, or it might yaw a bit on its own.  Here is where a compass cal can help.
2017-1-2
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Labroides
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Makirichi Posted at 2017-1-2 11:02
Hi everyone,

I am new in drone department but not in RC plane hobby. First lift up of my new P4P on the rear deck for quick up/down trial only. GPS on full but the aircraft started to move away when stationary 1.2M vert. so I tried to move slowly the right joy stick to bring it back, then every direction,  but nothing happened, so I push forward left joystick to gain altitude cause drone was descending slowly, so it was working. I grab it as soon as I could to be safe enough and under props.

"Before leaving my deck it was shows in app that I have to calibrate the aircraft. I did not wanted to do it because in manual it said to do it only more than 1.5 M away from magnetic source like metal, magnet, power line etc..So what should I do now the app ask me to do it? As per comment here it almost have to be done in Factory? "

This sounds like you got that message because your Phantom was close to a lot of steel which distorted the earth's normal magnetic field.
Your Phantom's compass detected this and brought up the message.
To recalibrate there would be a mistake and taking the Phantom somewhere away from that magnetic influence is the correct thing to do.
It's never a good idea to launch from on top of steel or reinforced concrete.
2017-1-2
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richparry
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Labroides Posted at 2017-1-1 22:43
This is an interesting flight record.
I can't see a simple obvious cause but what I observed might be a good starting point for someone that wants to look further.

Labroides,

I was surprised you said the manual says to only calibrate the compass when the apps says to. I checked and you are absolutely right. As an old timer to the Phantom series I was convinced you were wrong, but you are right. I bet lots of folks miss that.

Do you suppose the dual compasses make routine calibration unnecessary. The engineer in me wonders why DJI no longer suggests routine compass calibration before flights. I'm very happy not to do the calibration dance.

Thanks,
Rich
2017-1-3
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Labroides
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richparry Posted at 2017-1-3 00:08
Labroides,

I was surprised you said the manual says to only calibrate the compass when the apps says to. I checked and you are absolutely right. As an old timer to the Phantom series I was convinced you were wrong, but you are right. I bet lots of folks miss that.

I'm not sure if the compass is (effectively) different. (maybe it is or maybe not)

But the wording in the old manuals was always quite dodgy when it came to compass calibration and recalibrating the compass was quite unnecessary.
I don't know if it really was necessary to calibrate out of the box because I always did it but I found that further recalibration was not needed (unless you made changes to the Phantom)

The new wording is still not perfect.
Most of the time the app would tell you that it's got a compass problem, it's likely that you have put your drone down on reinforced concrete or something like that and moving the Phantom away from the magnetic disturbance would be the correct action, not recalibration.
2017-1-3
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Rob8888
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Labroides Posted at 2017-1-2 01:54
The incident was a little puzzling because the Phantom maintained GPS the whole time and there is drifting in the record.
The Phantom normally can hold position in over 25 knot winds, more than many would guess.
If the wind was strong enough to defeat GPS position holding, you probably wouldn't have launched and RTH would have been impossible.

So last night I did an hour flying in very wind conditions at the top of my small farm. No problems since.  

I spent the time learning how to retrieve the P4P if it blows away in strong wind again after loosing GPS hold, using visual, instruments and camera.  Quite disconcerting to see the P4P go from a fixed hover to 25km/h in a few seconds when flicking to Atti. No wondered my blow away was so dramatic when it happened unexpectedly.

I'm now 90% convinced that what happened was that the craft dropped GPS and went to Atti mode without reporting it.  So strange when RTH still worked fine.  I feel much more confident now in recovering the fast unravelling situation manually now (even though it was gone so quickly). Mentally logging wind direction prior to lift off is good practice, something that GPS support/hold tends to make less relevant.  Good lesson.
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Nigel_
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Labroides Posted at 2017-1-1 22:43
This is an interesting flight record.
I can't see a simple obvious cause but what I observed might be a good starting point for someone that wants to look further.

"There is some unaccounted horizontal drifting that puzzles me."

When analysing the logs, always remember that the position given in the log may not be the true position, it is only an estimate of the true position which may or may not be derived from the GPS receiver.  Also, even though the logs give the position to the nearest 10cm, the GPS receiver is never capable of achieving that accuracy and sometimes is nowhere near that accuracy and has a lot of drift over time.

If the aircraft is holding position using optical positioning and the GPS location drifts due to GPS inaccuracy then you will see horizontal drifting in the log even though the aircraft has not moved.  Also, if it can't get a GPS location for some reason then it will estimate the current position and that estimate, which is what we see in the logs, may drift further and further away from the actual position until it gets a good GPS fix.  It wont drop into atti mode immediately it fails to receive 1 accurate GPS position so we don't get to see a lot of drop outs and there is no GPS accuracy figure in the log that is decoded by phantomhelp so we never know the accuracy or drift of the GPS signal, it could easily drift 100m out on occasion without us knowing.  Normally, because of the optical positioning when near the ground, we never notice an inaccurate GPS unless we press RTH and it lands some distance from the take-off position.  I normally land using RTH and I've never yet had the P4 land back on it's box where it took off from, or even close enough to touch the box!
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Nigel_
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Rob8888 Posted at 2017-1-3 23:39
So last night I did an hour flying in very wind conditions at the top of my small farm. No problems since.  

I spent the time learning how to retrieve the P4P if it blows away in strong wind again after loosing GPS hold, using visual, instruments and camera.  Quite disconcerting to see the P4P go from a fixed hover to 25km/h in a few seconds when flicking to Atti. No wondered my blow away was so dramatic when it happened unexpectedly.


"Quite disconcerting to see the P4P go from a fixed hover to 25km/h in a few seconds when flicking to Atti."

Remember to keep practicing occasionally, if you haven't done it for a while then it can take a few seconds to get back into it, and that few seconds makes it a lot more difficult to get control back in time.

If you don't already have it turned on, make sure you have the aircraft flight tracks shown on the map, then you can easily fly it back into sight just using the aircraft symbol and track shown on the map.   Following the flight path to avoid obstacles may be better than gaining height to avoid obstacles and suffering higher wind speeds as a result.   But remember that if there is no GPS then the map is just an estimate, it may not come back into sight quite where you expect.
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theGrindLab.com
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richparry Posted at 2017-1-3 00:08
Labroides,

I was surprised you said the manual says to only calibrate the compass when the apps says to. I checked and you are absolutely right. As an old timer to the Phantom series I was convinced you were wrong, but you are right. I bet lots of folks miss that.

Same here. Why "always calibrate" before and "only calibrate when" now? Just curious. Also, where does is say in the manual that you should only calibrate under certain conditions? I am missing it.
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hallmark007
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theGrindLab.com Posted at 2017-1-4 12:42
Same here. Why "always calibrate" before and "only calibrate when" now? Just curious. Also, where does is say in the manual that you should only calibrate under certain conditions? I am missing it.

It does say on p57 of the Manual to only calibrate when prompted, the more people involuntary calibrate compass the more likely you will end up having a bad calibration.
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Snowwolfwarrior
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I had bad compass problems from word go,  came up with compass switch warning, so thought it prudent to calibrate, also never had a stable halt in flying
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theGrindLab.com
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hallmark007 Posted at 2017-1-4 13:01
It does say on p57 of the Manual to only calibrate when prompted, the more people involuntary calibrate compass the more likely you will end up having a bad calibration.

Thanks, hallmark007. I was looking at the Phantom 4 manual here:
https://dl.djicdn.com/downloads/ ... n_v1.2_20160805.pdf

Update: *I believe I see it on p51 in the P4 manual.
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theGrindLab.com Posted at 2017-1-4 13:31
Thanks, hallmark007. I was looking at the Phantom 4 manual here:

http://www.drone-world.com/dji-phantom-4-user-manual/

It's hard to really know if it's just change for p4p and Mavic, it could be something to do with dual compass I'm not qualified to tell you, but an answer with some detail from dji might clear up some confusion, certainly for users of previous aircraft who were somewhat brought up with a different different understanding about calibration .
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