Magnetometer Calibration
Posted: Sat May 18, 2019 2:54 am
Hi gang. Need some help in getting my GRT magnetometer calibrated. Here's the situation.
1. Magnetometer is located in my left wing, attached to the outer rib per GRT instructions.
2. It is just a tab bit over 18 inches from my left aileron.
3. I don't have a strobe, just LED nav light and an incandescent landing light. None of these, when powered up, interfere with the magnetometer.
4. Magnetometer is attached to an aluminum plate via brass hardware and Velcore. The plate is attached to the rib via brass hardware.
5. There is nothing else in that wing tip that could interfere with the operation of the magnetometer.
6. I've used a compass rose and when I line her up to N, turn on the EFIS the mag heading reads 030 degrees, which is supposed to be within the calibration range.
7. Moving the flight controls, turning on lights, etc none affects the magnetometer
8. I configured the AHRS and Magnetometer orientation correctly, e.g. AHRS - Top facing aft and the connector on the Right. Magnetometer - Top facing out from the wing rib and the connector facing aft. In this position the magnetometer is parallel to the longitudinal axis of the aircraft.
9. When I start rotating the aircraft to the left, the RED line starts within the 30 degree upper line, crosses over the center line (359 degrees) and stays within the lower 30 degree line for a short while and then suddenly drops off the chart and I get the "cannot calibrate" limits exceeded.
I'm sure many of you have gone through this magnetometer calibration scenario and I hoping to draw upon your experience and advice as to how best to accomplish this task; the last of which I need to get my aircraft fully operational with everything operating.
Regards,
George
1. Magnetometer is located in my left wing, attached to the outer rib per GRT instructions.
2. It is just a tab bit over 18 inches from my left aileron.
3. I don't have a strobe, just LED nav light and an incandescent landing light. None of these, when powered up, interfere with the magnetometer.
4. Magnetometer is attached to an aluminum plate via brass hardware and Velcore. The plate is attached to the rib via brass hardware.
5. There is nothing else in that wing tip that could interfere with the operation of the magnetometer.
6. I've used a compass rose and when I line her up to N, turn on the EFIS the mag heading reads 030 degrees, which is supposed to be within the calibration range.
7. Moving the flight controls, turning on lights, etc none affects the magnetometer
8. I configured the AHRS and Magnetometer orientation correctly, e.g. AHRS - Top facing aft and the connector on the Right. Magnetometer - Top facing out from the wing rib and the connector facing aft. In this position the magnetometer is parallel to the longitudinal axis of the aircraft.
9. When I start rotating the aircraft to the left, the RED line starts within the 30 degree upper line, crosses over the center line (359 degrees) and stays within the lower 30 degree line for a short while and then suddenly drops off the chart and I get the "cannot calibrate" limits exceeded.
I'm sure many of you have gone through this magnetometer calibration scenario and I hoping to draw upon your experience and advice as to how best to accomplish this task; the last of which I need to get my aircraft fully operational with everything operating.
Regards,
George