I will be traveling this weekend about 250 miles from where my original compass calibration took place on my first ever Mavic flight. From my understanding if I travel outside of 100 miles from this point a calibration is strongly recommended. Should I calibrate? Or only do it if the Go4 app recommends it?

From the manual: "Only calibrate the compass when the DJI Go app or the status indicator prompt you to do so."

I am just not sure an app with a 2.8 rating is trustworthy enough. So I just do it anyway, or follow the manual? I also will be doing some flying in the Charleston SC harbor during this time as well.

I am just not sure an app with a 2.8 rating is trustworthy enough.

The app itself isn't really doing the calibration. And anyway, by that logic you shouldn't be flying with it at all, right?

So I just do it anyway, or follow the manual?

I recommend following the manufacturer's suggestion, especially since this has worked well for many of us, but of course it's ultimately your choice. If you did happen to crash and approached DJI for a repair or replacement, which do you think would be better: to tell them you did or did not follow their guidelines regarding calibration?

M4BMW Posted at 2017-2-22 09:01
I am just not sure an app with a 2.8 rating is trustworthy enough. So I just do it anyway, or follow the manual? I also will be doing some flying in the Charleston SC harbor during this time as well.

Don't follow  the app because a lot of newbies act like they are seasoned pilots and then they screw up and blame it on everything else (app, drone, the dog , the cat even the wife) except PILOT ERROR AND IGNORANCE because they did NOT read the manual.

So it is up to you to follow advice  or NOT...If the AC tells you

"Hey Bro..Am OK, Am Cool,   DON'T TURN ME AROUND LIKE A DOG CHASING IT'S TAIL"  

I would listen to the AC unless the AC says otherwise...

Good point DroneFlying and dronist. Mabey if more people would visit forums like these to educate themselves on preflight situations then they would enjoy the Mavic even more. I am sure that reading these forums have kept me out of tricky situations and have prepared me for anything that may go haywire during future flights. I appreciate all who take the time to teach us newbies like myself.

Another question if the app tells me to calibrate would be more beneficial to do it closer to the flight location or does that matter?

M4BMW Posted at 2017-2-22 09:25
Another question if the app tells me to calibrate would be more beneficial to do it closer to the flight location or does that matter?

You are welcome...!!

My take...

When I arrive to the location. I usually check for metal , cell towers, railing, cement blocks etc. Away from your car and then turn on the RC, AC APP, if it says calibrate then I will calibrate.

So always check when the app is turned on. Let say your turn your RC,AC,APP in your home next to computer, WIFI etc the app would, most of the time, ask you to calibrate because of strong interference but DON'T DO IT...

Again, always at the location when you are ready to fly the app will tel you if you need to calibrate. It is says NORMAL that mean you are good to go.

M4BMW Posted at 2017-2-22 09:25
Another question if the app tells me to calibrate would be more beneficial to do it closer to the flight location or does that matter?

As long as it's done correctly -- including being well away from sources of magnetic interference -- it doesn't really matter where it's done. Given that, if you're being prompted to do it before your trip and have a suitable and convenient location at home, I'd go ahead and do it before traveling.

M4BMW Posted at 2017-2-22 09:25
Another question if the app tells me to calibrate would be more beneficial to do it closer to the flight location or does that matter?

You shouldn't need to calibrate only if app prompts, I recently travelled 350 miles to Scotland and I didn't need to calibrate.

How ever, when starting your first flight I would recommend you raise the AC to about 10 feet just let it hover for a minute, then just fly forward about two feet backward two feet up down and yaw right and left, if everything looks ok , enjoy the flying.

Have a nice break..

Thanks for the addtional tips hallmark, I would not have thought to do this if you hadn't mentioned it.

I've flown mine straight out the box from new, no compass calibration as app never asked for it.
I do always check IMU and compass are good to go under the sensors section though before I take off.

Good point as well, less green is better correct?

M4BMW Posted at 2017-2-22 10:04
Thanks for the addtional tips hallmark, I would not have thought to do this if you hadn't mentioned it.

My Mavic was built and calibrated in China. It was shipped about 8,000km to Germany. I flew it without calibration. I travelled about 4,000km and flew it without calibration. I went back to Germany and flew it without calibration. I did not have any issues and have never been prompted to calibrate the Mavic.

That said, I doubt that a distance of 250 miles will require you to calibrate the Mavic. And I support what the others said: The manual clearly says, only calibrate when prompted to do so. I'd follow that advice.

Sounds like there is alot of knowledge on here. Now, say if i am prompted to calibrate if I am out at sea? My guess is I'm dead in the water as they say.

M4BMW Posted at 2017-2-22 10:16
Sounds like there is alot of knowledge on here. Now, say if i am prompted to calibrate if I am out at sea? My guess is I'm dead in the water as they say.

As long as it's done correctly -- including being well away from sources of magnetic interference -- it doesn't really matter where it's done.

Good to know, I have read somewhere that the bow would be the best place away from the motor.

M4BMW Posted at 2017-2-22 10:33
Good to know, I have read somewhere that the bow would be the best place away from the motor.

I have never calibrated mine since arrival, got it in Sweden flied 4 hours there went to germany 2300 km flied a couple of hours no indication in the app that it needed calibration, flew back to sweden (what a battery {:4_181:} capacity) with the AC in the luggage of course and some more hours there so all in all 4600 km movement, no need for calibration.

Yes . I belive you. No compass calibration unless prompted. Thats what the manual says on page  50. But on the next page under the title  When to recalibrate DJI say " when flying in a new location  that is different from the most recent flight" .

I'm prompted to calibrate my compass at nearly every flight location, even if the previous flight was only a few miles away. I'm very surprised to hear of people traveling a couple hundred or even thousand KM and not being prompted to do so.

fansc2962bbc Posted at 2017-2-22 14:32
Yes . I belive you. No compass calibration unless prompted. Thats what the manual says on page  50. But on the next page under the title  When to recalibrate DJI say " when flying in a new location  that is different from the most recent flight" .

I think you can take that to read you can expect to be prompted to recalibrate the compass when flying in a new area. That's certainly been my experience.

i thought u were supposed to calibrate compass if u travel more than 20 miles from last calibration

boostedford Posted at 2017-2-22 19:01
i thought u were supposed to calibrate compass if u travel more than 20 miles from last calibration

Nooooooooooooooo

Ex Machina Posted at 2017-2-22 14:56
I'm prompted to calibrate my compass at nearly every flight location, even if the previous flight was only a few miles away. I'm very surprised to hear of people traveling a couple hundred or even thousand KM and not being prompted to do so.

Ex, this is almost impossible. If you are seeing CALIBRATE it doesn't mean calibrate if it says NORMAL next to it.

The warning would come when you turn the app on after turning the RC,AC and if you see the RED TRIANGLE SAYING WARNING need to calibrate then you calibrate.

dronist Posted at 2017-2-22 19:35
Nooooooooooooooo

this was the common knowledge when i had my phantom 2 vision+ has it changed?

boostedford Posted at 2017-2-22 19:53
this was the common knowledge when i had my phantom 2 vision+ has it changed?

Yessssssssssssssssss

dronist Posted at 2017-2-22 19:39
Ex, this is almost impossible. If you are seeing CALIBRATE it doesn't mean calibrate if it says NORMAL next to it.

The warning would come when you turn the app on after turning the RC,AC and if you see the RED TRIANGLE SAYING WARNING need to calibrate then you calibrate.

That's exactly what I see many if not most times -- the prompt to calibrate.

When you recalibrate your Mavic Compass, you are taking a snapshot of 2 things. The first is you are measuring the local magnetic declination. This is the difference between true north, and the north your compass points to. The Mavic needs this to match the GPS north to the north measured by the compass. If they don't agree, bad things like TBE can occur. Declination varies depending your location, and in some areas of the globe changes much quicker than other areas. The other snapshot you are taking is local magnetic influences immediate to that area or accessories you may have on your drone. Hopefully if you have nothing magnetic around your drone, only magnetic declination will be accounted for.


In some cases traveling 1000 miles will not change your magnetic declination. In other cases, traveling a hundred miles could change, so for someone to say they traveled thousands of miles with no need for a calibration may be correct if they are traveling along a line of magnetic declination. Check out the link below for a world map showing lines of declination in various areas. You'll see that in some areas, 100 miles can make a large difference depending whether you are traveling along a line of declination or perpendicular to a line.


https://maps.ngdc.noaa.gov/viewers/historical_declination/

I'm pretty sure if the Mavic is not happy it will ask for a calibration before letting you fly.

• I have been asked on 2 occasions now, one at a park and one just outside my house.
  

If it doesn't ask you, I'm sure it's ok and you can simply take off 3/4 meters and see if it does anything abnormal, if so, land and perform the calibration.

Ex Machina Posted at 2017-2-22 20:16
That's exactly what I see many if not most times -- the prompt to calibrate.

The RED TRIANGLE SAYING WARNING???

Do you carry any metals,or their any metals on/in your body?

From where you usually fly?

Am curious at to why keep asking you to calibrate?

Ex Machina Posted at 2017-2-22 14:56
I'm prompted to calibrate my compass at nearly every flight location, even if the previous flight was only a few miles away. I'm very surprised to hear of people traveling a couple hundred or even thousand KM and not being prompted to do so.

Do you carry anything magnetic with you?

dronist Posted at 2017-2-22 19:35
Nooooooooooooooo

OK folks... here's an engineer's opinion.  I believe the Mavic contains a dual compass.  It is my opinion that the app will require calibration if there is a discrepancy between the two.  

That situation may or may not be true when you change locations so you may or may not be prompted to recalibrate.  If there is no discrepancy, it is safe to fly, but be aware of the caveat below.

What is true regarding changing locations is that the compass will not be correct due to Earth's magnetic deviation.  I'm not sure if or how calibration accounts for this, but if you or the software is concerned about which way the drone is pointed or flying, then the magnetic declination needs to be accounted for.   Again, I don't know if compass calibration accounts for this, but I always re calibrate when I move more than 100 miles and I've never had a problem doing so.
EDIT:  Just noticed the post above by fans06b77ccc. That says it all.  WELL DONE fans06b77ccc.

fans06b77ccc Posted at 2017-2-22 20:51
When you recalibrate your Mavic Compass, you are taking a snapshot of 2 things. The first is you are measuring the local magnetic declination. This is the difference between true north, and the north your compass points to. The Mavic needs this to match the GPS north to the north measured by the compass. If they don't agree, bad things like TBE can occur. Declination varies depending your location, and in some areas of the globe changes much quicker than other areas. The other snapshot you are taking is local magnetic influences immediate to that area or accessories you may have on your drone. Hopefully if you have nothing magnetic around your drone, only magnetic declination will be accounted for.

Good post.  Just as a matter of curiosity, do you have any idea how one would calibrate true north.  I suppose it could be done by knowing your current location and using a declination table, but I was wondering if there might be some other way of determining true north.  When I was flying real planes, we always adjusted the magnetic compass to to the runway direction just before takeoff :-)

Ex Machina Posted at 2017-2-22 20:16
That's exactly what I see many if not most times -- the prompt to calibrate.

even after the mavic has fully powered up/gotten all satellites/IMU fully initialized? If so, that's interesting. I get the red notification on power on of the app and upon immediate poweron of the Mavic too. But the red indicator to calibrate disappears on its own within seconds almost..after the Mavic fully comes online

dronist Posted at 2017-2-22 21:22
The RED TRIANGLE SAYING WARNING???

Do you carry any metals,or their any metals on/in your body?

I live in the Washinton, DC area, so I have to travel at least 15 miles from home to fly. So far my range has typically been 17-50 miles west, south, and east.

On iOS, when you connect to the Mavic you either go directly to the RC control screen if all is good or you are shown the prefs screen wth a prompt to calibrate active for whatever needs attending.

I keep a few yards between the Mavic and the RC, keys, etc. when prompted to calibrate the compass, but I don't take off my watch or belt, and I have four titanium plates in my skull.

I am in the same area and doing the same travel and I have yet to have it to tell me to calibrate.  I have been flying at the same place over and over however.  I will be going about 80 miles south this weekend and will be flying.  I will see if it changes for me.  Out of the box I never calibrated and it is solid so far.  

Would there be a point at the green status bar reading wise in which you may want to recalibrate, even though you have not been asked to? What is the magical number it needs to reach in order for a calibration?

Ex Machina Posted at 2017-2-23 08:38
I live in the Washinton, DC area, so I have to travel at least 15 miles from home to fly. So far my range has typically been 17-50 miles west, south, and east.

On iOS, when you connect to the Mavic you either go directly to the RC control screen if all is good or you are shown the prefs screen wth a prompt to calibrate active for whatever needs attending.

So probably that is the reason...

Curious, did you have anyone else turn on and the RC/AC/APP while you are far away from the AC?

Interesting to see if it will prompt to do calibration.

M4BMW Posted at 2017-2-23 09:00
Would there be a point at the green status bar reading wise in which you may want to recalibrate, even though you have not been asked to? What is the magical number it needs to reach in order for a calibration?

As long as you have green you are good. Again you would receive a RED TRIANGLE with exclamation mark inside of it and it says WARNING.

Or if you are near a strong magnatci intereference it will show on the top left of the APP where you suusally you see ready to fly , GPS LOCK etc...
So if you know you are then try to move the AC location and start again.

dronist Posted at 2017-2-23 11:37
So probably that is the reason...

Curious, did you have anyone else turn on and the RC/AC/APP while you are far away from the AC?

I usually set down the Mavic where I want to launch, turn it on, then walk a few yards away where I've left my bag and the RC, keys, etc., then launch the app, connect to the RC and turn on the RC.

By the time the AC boots I'm yards away.