I had the opportunity to fly the spark over at 3 different areas quite far apart over the past week. The first stage and the second stage flying was about 450km away and the third stage over 3000km.

In the first two stage, no IMU or compass issue or recalibration was required or prompted and the AC fly without problem.

In the third stage I received compass interference (IMU is OK though). so I calibrate the compass as the DJI Go 4 app instructed and fly without any issues.

But then on the second battery I received the again compass interference. This time as I lifted the AC above ground, the all green to fly appear. So possibly it was the lift off area having some iron in the ground or reinforced steel rod in concrete pathways.

So the next time you receive compass inteference try to move the lift off area to another place or use gesture mode for lift off. Beats the need for recalibrating the compass.

I believe the rule is fine to only calibrate the IMU or compass when the DJI Go 4 app recommend it BUT try moving the AC to another location or try gesture mode lift off first, if it is possible to get the greenlight to fly rather than doing recalibration in a surrounding that is abnormal in itself.

My 2 cents.

I had the opportunity to fly the spark over at 3 different areas quite far apart over the past week. The first stage and the second stage flying was about 450km away and the third stage over 3000km.

In the first two stage, no IMU or compass issue or recalibration was required or prompted and the AC fly without problem.

In the third stage I received compass interference (IMU is OK though). so I calibrate the compass as the DJI Go 4 app instructed and fly without any issues.

But then on the second battery I received the again compass interference. This time as I lifted the AC above ground, the all green to fly appear. So possibly it was the lift off area having some iron in the ground or reinforced steel rod in concrete pathways.

So the next time you receive compass inteference try to move the lift off area to another place or use gesture mode for lift off. Beats the need for recalibrating the compass.

I believe the rule is fine to only calibrate the IMU or compass when the DJI Go 4 app recommend it BUT try moving the AC to another location or try gesture mode lift off first, if it is possible to get the greenlight to fly rather than doing recalibration in a surrounding that is abnormal in itself.

My 2 cents.