Spin & crashed!

Meta4 · Nov 7, 2019

cheddarman said:
I have to say that after 18 months lying on a shelf I would calibrate. In fact I calibrate at any new location I go to. It's an individual choice.

It's an individual choice for people that don't understand what calibrating the compass actually does and when it's necessary.
Unnecessary recalibrating does nothing at all to make your flights safer.
I'd suggest checking what DJI say on the subject:

cheddarman said:
At no time was he flying above 90 feet over all those houses. I wonder if there was some sort of interference somewhere along the route?

Interference is common in urban areas, but it doesn't make one motor stop working properly.
At worst, it might swamp the control signal and trigger RTH.

cheddarman said:
He started to lose height at 0.43 and just steadily dropped to the ground.
At the latter part of the flight the battery cells were showing some deviation but still at 95% capacity.

The battery doesn't look very healthy and voltage dropped significantly when the pilot tried to climb.
But a low battery doesn't cause one motor to stop.
It just triggers an autolanding.

The compass, interference and battery were not factors that contributed to this crash

cheddarman · Nov 8, 2019

Again I think the data file, if available, would be very helpful.

Gizmoh · Nov 8, 2019

cheddarman said:
Again I think the data file, if available, would be very helpful.

The earliest file (300MB) with timestamp 18:13.

https://filebin.net/7xsh2otz0xgmru9v/FLY149.DAT?t=qzt9xzlr

bsartist · Nov 8, 2019

Meta4 said:
There's no problem with that.
The drone's own magnetic fields don't change unless you modify or rebuild the drone so there shouldn't be any need to recalibrate.
I still haven't calibrated anything on my 3 year old P4 pro.\ and it flies perfectly.

The calibration myths won’t die.

cheddarman · Nov 8, 2019

Every time I turn every thing on, and this was this afternoon, I get this, so you say ignore it?

bsartist · Nov 8, 2019

Meta4 said:
Unnecessary recalibrating does nothing at all to make your flights safer.

In fact, I believe that it could make your fights unsafe. If you calibrate in the presence of external magnetic interference, you could MIScalibrate and cause problems once you take off and leave the local disturbance.

bsartist · Nov 8, 2019

cheddarman said:
Every time I turn every thing on, and this was this afternoon, I get this, so you say ignore it?

View attachment 115486

Did you get a warning saying to calibrate your compass? I didn’t see one here. But if you did, then you should calibrate then, and only then. This screencap shows as “normal”

cheddarman · Nov 8, 2019

bsartist said:
In fact, I believe that it could make your fights unsafe. If you calibrate in the presence of external magnetic interference, you could MIScalibrate and cause problems once you take off and leave the local disturbance.

I think that is fairly obvious but then how does one know if there is a "presence" where you want to fly

I certainly found one when I flew alongside a combine harvester, ended up in the grain trailer?

bsartist · Nov 8, 2019

cheddarman said:
I think that is fairly obvious but then how does one know if there is a "presence" where you want to fly
I certainly found one when I flew alongside a combine harvester, ended up in the grain trailer?

This is *precisely* why you only calibrate where you *know* there are no external magnetic influences. Because the more “promiscuous” you are in calibrating, the higher the chance you’ll get a dirty magnetic environment.

I calibrate on a piece of property I know has no buried metal. Then I leave it alone. Then I know I’m good.

cheddarman · Nov 8, 2019

Ah, got ya! Out here in the wilds of Devon I usually do it in the middle of a field!

bsartist · Nov 8, 2019

bsartist said:
This is *precisely* why you only calibrate where you *know* there are no external magnetic influences. Because the more “promiscuous” you are in calibrating, the higher the chance you’ll get a dirty magnetic environment.

I calibrate on a piece of property I know has no buried metal. Then I leave it alone. Then I know I’m good.

I should add that we may be confusing a couple concepts. Calibrating should be done only when directed by the software and in a mag free environment (well, within reason. Like maybe 10 or 15 ft from metal I think. Don’t quote me

. ) That calibrates the compass against any *internal* interference. That’s a constant.

But if you get to a site where you are ready to take off with magnetic interference and compass errors, that’s telling you not to take off. Not to calibrate in the interference field.

Bottom line, don’t calibrate unless you are reasonably sure you are not near magnetic interference or ferrous metals.

RodPad · Nov 8, 2019

@cheddarman,

Did you not believe what @Fly Dawg said in this post?
Spin & crashed!

In this post I thought it funny it appears your indoors.

Spin & crashed!

In the past, I had the same thought pattern as you, it was here and I lot of @Meta4 posts and others that were mostly related to crashes. That I finally figured it out.

Your screen you posted is not warning for you to do a compass calibration.

Try this,
Power up your Phantom, Remote, Etc. Just like your screen shot. Then set the Phantom on the hood of your car.
Let us know what messages pop up.

Problem is we or I can't predict what it will be, because its going to very by Phantom model, and firmware, etc.

Rod

RodPad · Nov 8, 2019

@cheddarman,
From other posts you are using a P3A and DJI-GO.

I will try to test my own tomorrow.

@Gizmoh,
Its still your thread....
and its your turn...

.

Rod

cheddarman · Nov 9, 2019

bsartist said:
Did you get a warning saying to calibrate your compass? I didn’t see one here. But if you did, then you should calibrate then, and only then. This screencap shows as “normal”

I thought the outlined "calibrate" was just that, saying calibrate? I will say no more.

Gizmoh, over to you - sorry to hijack your thread!

Meta4 · Nov 9, 2019

cheddarman said:
I thought the outlined "calibrate" was just that, saying calibrate?

DJI confuses a lot of people with that.
It's not suggesting that calibration is required.
It's the button to push in the rare event that you need to calibrate the drone.

RodPad · Nov 9, 2019

Yes very stupid Calibrate / Normal, same as the name DJI-Go.
They should change it to this CALIBRATE! / normal. That's how it looks to most of us anyway.

Rod

cheddarman · Nov 9, 2019

Glad of that! I thought my 81 year old logic was losing it!

RodPad · Nov 9, 2019

My memory is fairly good on certain things, I pretty sure I have a post replying to @Meta4 like "I going to re calibrate every time I move my location"

@cheddarman,
Have you looked at the .dat file that @Gizmoh provided in this post:: Spin & crashed!

I think he is waiting for you!

Rod

cheddarman · Nov 9, 2019

From the file he loaded, FLY.DAT 149, all 300Mb of it, I'm afraid I cannot get any actual flight data from it, . Whether it's a MAC thing I don't know.

Fly Dawg????

RodPad · Nov 10, 2019

cheddarman said:
From the file he loaded, FLY.DAT 149, all 300Mb of it, I'm afraid I cannot get any actual flight data from it, . Whether it's a MAC thing I don't know.

Fly Dawg????

Dude you made my day!
On this post, I stated:
"I'm glad you got to study your own dat files, I will ask you for help when I get that urge."
Is it possible to format/erase the internal memory?.

@Fly Dawg, @BudWalker, @Oso

Rod