An example of bad compass calibration

Trackman1 · Jan 14, 2016

Found this video of screen telemetry when pilot had a poor compass calibration.
Pilot is skilled enough that not much happened and he retains control.
But from watching this it is easy to see how a novice pilot could become confused and lose control.
Noticed his flight mode changing by itself. Also see what happens when he goes for RTH.

Tommymonkey · Jan 14, 2016

Trackman1 said:
Found this video of screen telemetry when pilot had a poor compass calibration.
Pilot is skilled enough that not much happened and he retains control.
But from watching this it is easy to see how a novice pilot could become confused and lose control.
Noticed his flight mode changing by itself. Also see what happens when he goes for RTH.

I seen that video now I always check my Red arrow on map facing the correct position after taking off.

ianwood · Jan 14, 2016

Notice how bad the horizon is as well as the circling movements. That's indicative of bad compass calibration. Also note that compass error only comes up sporadically. It can often not come up at all. The P3 doesn't do the best job of detecting compass issues.

RasterEyes · Jan 14, 2016

Just to mention the cause of the error is likely from flying too close to the ship. The antennas on ships can cause issues.

[[A more complete answer is listed further below. I am sure I have read about p antennae issues but I'm going to have to dig to see where I found that info! Lol. But do see the explanation based on calibrating the. Compass in a bad environment]]

Sent from my iPad using PhantomPilots mobile app

SouthernPhantom · Jan 14, 2016

I just traveled from the Georgia to Colorado and took my P3P for some winter-scape photos. I totally forgot to recalibrate the compass, but it flew perfectly every time. But I'm good about easing it up in steps, and keeping an eye on its stability.

Travis726 · Jan 14, 2016

If something like this happens you could switch to atti and fly it fine (without gps obviously) correct?

4wd · Jan 14, 2016

Another take home message is if things don't seem quite right soon after take off it's unlikely to get any better if you just press on.

SouthernPhantom · Jan 14, 2016

Travis726 said:
If something like this happens you could switch to atti and fly it fine (without gps obviously) correct?

Well, yes and no. (How's that for a definitive answer?) It depends what's causing the interference. The GPS and compass sensors are two different systems. And, to fly in atti mode requires advance practice, because it needs much-more hands-on control. But under the right circumstances, it would hopefully reduce the whatever is causing the Phantom's interference.

Travis726 · Jan 14, 2016

SouthernPhantom said:
Well, yes and no. (How's that for a definitive answer?) It depends what's causing the interference. The GPS and compass sensors are two different systems. And, to fly in atti mode requires advance practice, because it needs much-more hands-on control. But under the right circumstances, it would hopefully reduce the whatever is causing the Phantom's interference.

Yeah I am learning on a syma x5sc while I wait for my tax return so I have a feel for it and get better every day. No compass or gps there

Rumbaar · Jan 14, 2016

4wd said:
Another take home message is if things don't seem quite right soon after take off it's unlikely to get any better if you just press on.

Yes, only a few flights for me. But the last had warning issues after take off of compass issues. Immediately landed and checked calibration.

BudWalker · Jan 14, 2016

Trackman1 said:
Found this video of screen telemetry when pilot had a poor compass calibration.
Pilot is skilled enough that not much happened and he retains control.
But from watching this it is easy to see how a novice pilot could become confused and lose control.
Noticed his flight mode changing by itself. Also see what happens when he goes for RTH.

I'd REALLY like to get the .DAT file for this flight. Could you provide it please. It will be a real help in understanding what to expect in the .DAT when there are compass problems in a flight. The documentation from the video will make it really easy to know where to look in the .DAT. Thanks.

Rumbaar · Jan 14, 2016

BudWalker said:
I'd REALLY like to get the .DAT file for this flight. Could you provide it please. It will be a real help in understanding what to expect in the .DAT when there are compass problems in a flight. The documentation from the video will make it really easy to know where to look in the .DAT. Thanks.

Safe to assume they found the video online and are not the operator of the drone, so wouldn't have access to that information.

BudWalker · Jan 14, 2016

Yeah, I see that now. Bummer.

Oso · Jan 14, 2016

BudWalker said:
Yeah, I see that now. Bummer.

You can try to contact him here. I think his name is Mike and he's from Canada.
cdnstudman

BudWalker · Jan 14, 2016

Oso said:
You can try to contact him here. I think his name is Mike and he's from Canada.
cdnstudman

Thanks.

ianwood · Jan 14, 2016

RasterEyes said:
Just to mention the cause of the error is likely from flying too close to the ship. The antennas on ships can cause issues.

No. The ship will have a magnetic field. But only if you calibrate or take off too close to it or fly right next to it, will you have issues. The antennas on the ship will do little.

Trackman1 · Jan 14, 2016

BudWalker said:
I'd REALLY like to get the .DAT file for this flight. Could you provide it please. It will be a real help in understanding what to expect in the .DAT when there are compass problems in a flight. The documentation from the video will make it really easy to know where to look in the .DAT. Thanks.

This just a link to someone's Utube video. I do not know the owner. He has another one, where he fly's one mile out to a ship. He does it both from the SD card video and a screen capture of the telemetry.

Wolfiesden · Jan 14, 2016

Possible the compass error could have been caused by the mass steel of the ship and or any RF emissions it may be putting out (radar, ship to shore, etc).

Wolfiesden · Jan 14, 2016

ianwood said:
No. The ship will have a magnetic field. But only if you calibrate or take off too close to it or fly right next to it, will you have issues. The antennas on the ship will do little.

The video had him taking off in close proximity to the ship as it came down the channel.

Meta4 · Jan 14, 2016

RasterEyes said:
Just to mention the cause of the error is likely from flying too close to the ship. The antennas on ships can cause issues.

Wolfiesden said:
Possible the compass error could have been caused by the mass steel of the ship and or any RF emissions it may be putting out (radar, ship to shore, etc).

This has nothing at all to do with the ship or its antennas and everything to do with unnecessarily calibrating his compass on a pier lined with steel sheet piling.

Wolfiesden said:
The video had him taking off in close proximity to the ship as it came down the channel.

The magnetic effect of a steel object depend upon the size of the object and how close it is.
He calibrated right on top of the pier which had a substantial amount of steel visible.
This would have had much more effect than the ship at that distance (inverse square law applies).

This is another example of the problems you risk if you think you feel you should calibrate every flight.