Everytime I go to a new location I check the ground to avoid false magnetism that can disturb the compass during take-off. This is usually from iron reinforced concrete in the ground, but can also be from electric power lines or installation.

Here is a very bad one, where compass needle was wrong and when checking with telemetry on the Graupner RC-transmitter it hit 170% earth magnet field. The inclination at 62 degrees is close to the theoretical local 66 degree in parentheses, that is because the location of the magnet disturbance is a local urban electric sub-station 20-30 m ahead in Belval LU. Obviously this is not a good location to start from.

I have earlier flown over this location at 9 m height and the micro-copter beeped away with magnet error. Rising and moving 20 m away stopped the magnet error.

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In general about Magnet Errors

What is highest / lowest earth magnet field that you have encountered?

What is highest / lowest inclination compared to theoretical local inclination?

Please remember it must be a real location, not you playing with a magnet in front of the micro-copter.

Show photo or it did not happen! We want to see proof! ;)
« Bearbeitet von Foersom am 09.10.2016 13:44. »