Here is the final answer from DJI for the difference between P4P 1.0 and 2.0. In conclusion, my P4P v2.0 is working as it should.
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Please remember that the magnetic waves change from area to area. What I assume DJI is trying to prevent is future fly aways due to compass misreadings.Thanks for posting that. It seems that the P4P Pro has similar firmware controls as the Mavic 2. It's disappointing though - the 30 day calibration may be somewhat defensible on the basis that the magnetic field of the aircraft may change over time if it is exposed to strong magnetic fields, but the 50 km requirement is just silly - I cannot see any scientific basis for that at all. They had stopped even advising recalibration when changing location for most models, so this is not even a consistent requirement.
Please remember that the magnetic waves change from area to area. What I assume DJI is trying to prevent is future fly aways due to compass misreadings.
If you put it that way, then DJI just wants you to do the calibration dance, just to amuse themselves. Everytime you get “calibrate your compass” they go “look look at the idiot doing the dance” and laugh about it. They have to balance their lives. They grew tired of the idiots who called to blame DJI for their crashes and took revenge.Ah yes - that old misunderstanding again. The earth's field changes in strength, declination and inclination, but the compass calibration doesn't measure those - it's sole purpose is to determine the aircraft's magnetic field so that it can subtract it from the total measured field in flight. In particular the declination, which is the difference between magnetic north and true north, and is needed in order to relate the compass reading to the aircraft heading in the true north frame of reference, cannot be measured by any calibration method and is instead computed by the FC from a global magnetic field model in the firmware.
If you put it that way, then DJI just wants you to do the calibration dance, just to amuse themselves. Everytime you get “calibrate your compass” they go “look look at the idiot doing the dance” and laugh about it. They have to balance their lives. They grew tired of the idiots who called to blame DJI for their crashes and took revenge.
I am no expert, but I have seen with my own eyes how interference with the compass has caused my phantom to fly away, twice. I can complete my mision, be on my way returning home then the bird steers left on it’s own and flies away at full speed. It is a scary few milliseconds while I switch to ATTI and regain control. Ever since I do recalibration of the compass (even if it does it no favors), I haven’t had any more flyaways.There may well be an element of DJI just trying to cover themselves. The main compass issue, caused by taking off from a location with magnetic interference which results in the IMU yaw being initialized to the wrong value, is a difficult one for them to deal with. It's kind of pilot error but DJI has never provided useful advice on how to avoid it, even though there is a relatively simple and robust solution. In my opinion they would be better served simply advising everyone to check that the aircraft orientation arrow is pointed in the correct direction on the map before taking off. That simple check would have prevented the vast majority of the loss of control cases reported on this forum and the Mavic forum.
I am no expert, but I have seen with my own eyes how interference with the compass has caused my phantom to fly away, twice. I can complete my mision, be on my way returning home then the bird steers left on it’s own and flies away at full speed. It is a scary few milliseconds while I switch to ATTI and regain control. Ever since I do recalibration of the compass (even if it does it no favors), I haven’t had any more flyaways.
The only different factor in that specific flight was a 50 Kw generator being turned on. I know for a fact that generators emit a magnetic field of considerable size, since I’ve seen how it affects the compass before taking off near one.That description is hard to diagnose, but doesn't sound like a mis-calibrated compass - that should show up as soon as you start to fly. The same goes for magnetic interference at the takeoff point. I'd suggest that you take a look at the flight log - all the data needed to diagnose any compass issues are in the logs.
The only different factor in that specific flight was a 50 Kw generator being turned on. I know for a fact that generators emit a magnetic field of considerable size, since I’ve seen how it affects the compass before taking off near one.
Edited my post above to finally say what I wanted to transmit.It's just speculation without the data. The magnetic field from a generator is not going to extend more than a few meters at most.
The only different factor in that specific flight was a 50 Kw generator being turned on. I know for a fact that generators emit a magnetic field of considerable size, since I’ve seen how it affects the compass before taking off near one.
Edit: My point is, that when you calibrate, perhaps the drone takes into consideration any interference in the area and adjusts it’s math to consider this variable. Please bare in mind that I am no expert and am simply guessing.
I teach my students after the drone takes off to let it settle at the auto take off height of about 5 feet then inspect the drone, and check the controls and then the monitor for warnings. I guess that is the value of an education. Plus no fly aways, great video I'll be sure to use this article in my class.Recently I caught myself making a Mistake that most likely I have been making On every single flight I have taken over the last 2 years.
In those last 2 years I have had two fly aways and each one DJI refunded me with 100% coupon for a brand new drone and that is great but the fault was most likely mine.
I recently had a Revelation of sorts that I take my eyes off of the Display to watch my drone take off into the sky for the first couple minutes and in doing so miss any error messages that might have popped on the screen such as Compass error / Magnetic Interference errors to name a few.
This could explain how I missed the critical errors that might have saved me from a fly away right on take off.
I have tried to break this habbit but it is very difficutl as my eyes just want to watch that take off as the drone is so close.
Obviously we are more at risk than most as we fly from some really bad advantage points , so I made this video to show how dangerous it can be to miss the Flash or an error message come across the screen especially at take off.
The video shows how little Magnetic Interference it takes to put your Drone in Jeopardy of a Fly Away and how deceiving it can be to continue to fly.
When it comes to magnetic Interference , it can take many forms, Compass error / Yaw Errors / Atti Mode.
The best advice I can share is do not trust your drone to fly after you get an error no matter how fast it appears on the screen, as the damage is most likely already done.
Best to shutdown , move your take off position and start again.
Phantomrain.org
Approved Vendor
Recently I caught myself making a Mistake that most likely I have been making On every single flight I have taken over the last 2 years.
In those last 2 years I have had two fly aways and each one DJI refunded me with 100% coupon for a brand new drone and that is great but the fault was most likely mine.
I recently had a Revelation of sorts that I take my eyes off of the Display to watch my drone take off into the sky for the first couple minutes and in doing so miss any error messages that might have popped on the screen such as Compass error / Magnetic Interference errors to name a few.
This could explain how I missed the critical errors that might have saved me from a fly away right on take off.
I have tried to break this habbit but it is very difficutl as my eyes just want to watch that take off as the drone is so close.
Obviously we are more at risk than most as we fly from some really bad advantage points , so I made this video to show how dangerous it can be to miss the Flash or an error message come across the screen especially at take off.
The video shows how little Magnetic Interference it takes to put your Drone in Jeopardy of a Fly Away and how deceiving it can be to continue to fly.
When it comes to magnetic Interference , it can take many forms, Compass error / Yaw Errors / Atti Mode.
The best advice I can share is do not trust your drone to fly after you get an error no matter how fast it appears on the screen, as the damage is most likely already done.
Best to shutdown , move your take off position and start again.
Phantomrain.org
Approved Vendor
In addition to checking your DJIGo4’s map to make sure your indicated aircraft heading is accurate, you may also want to check out your take off location before turning on your aircraft:
Metal Detector iOS App:
Metal Detector (PRO)
Example of flying near magnetic fields: