I'm new to DJI and have a MPP. According to my flight logs I have 3h5m flight time. I have owned and operated other drones so I'm not a newbie pilot. I'm looking for some advice on how to respond to some undesirable behavior in flight recently. Here's the story:
I updated the app and firmware. I calibrated the compass per the instructions when the craft hadn't been flown yet. I've been flying all 3 hours in the same area. I tend to have full bars and 17-18 satellites in the area.
When I powered on yesterday, there was a compass warning. I can't remember the exact phrasing and they were not in the logs, but it did not ask me to recalibrate, and after tapping on the the dialogue it went away and did not come back. I then took off, did some testing (flew up/down/sideways, etc) and everything seemed fine. I proceeded to fly for about 20 minutes, set the craft down, let it rest a few minutes, then put battery 2 in. No warnings.
Things went wonky from here.
2:08 into the flight I got a warning for a weak GPS signal. According to the log, it still had contact with 18 but the bars disappeared. Note that at this point in the log, there isn't a pop up/toast about it, just the background says.
2:08 - Warning: Compass Error. Exit P-GPS Mode.
2:09 - Warning: In Flight working IMU encounters heading exception, please switch to atti mode if craft behave abnormally (it switched to atti for me)
2:12 Warning: Weak GPS signal. Positional accuracy may be compromised. Please fly with caution.
So, the failures all happened pretty quick. Abnormal flight, check. The gimbal was shaking, there was some yaw, some shake and some shimmy and the craft was drifting. I did keep calm and bring the craft back safely - I had LoS and it was only about 800ft away, though I needed the camera to get my bearings. And guess what, all the systems came back online. I landed, took back off and did some flight testing. All seemed well. I landed and called it a day.
My questions:
a) When I saw those compass warnings, would it have been wise to recalibrate?
b) Was the compass failure even related to the warnings?
c) Was the weak GPS signal responsible?
d) Was it expected that the IMU would fail w/o GPS and compass? I understand that a compass failure shuts down the GPS by design, but what about the IMU?
e) Was this just a fluke or does this type of thing happen often?
f) What, if anything, should I do anything before flying again?
Thanks in advance for any insights.
I updated the app and firmware. I calibrated the compass per the instructions when the craft hadn't been flown yet. I've been flying all 3 hours in the same area. I tend to have full bars and 17-18 satellites in the area.
When I powered on yesterday, there was a compass warning. I can't remember the exact phrasing and they were not in the logs, but it did not ask me to recalibrate, and after tapping on the the dialogue it went away and did not come back. I then took off, did some testing (flew up/down/sideways, etc) and everything seemed fine. I proceeded to fly for about 20 minutes, set the craft down, let it rest a few minutes, then put battery 2 in. No warnings.
Things went wonky from here.
2:08 into the flight I got a warning for a weak GPS signal. According to the log, it still had contact with 18 but the bars disappeared. Note that at this point in the log, there isn't a pop up/toast about it, just the background says.
2:08 - Warning: Compass Error. Exit P-GPS Mode.
2:09 - Warning: In Flight working IMU encounters heading exception, please switch to atti mode if craft behave abnormally (it switched to atti for me)
2:12 Warning: Weak GPS signal. Positional accuracy may be compromised. Please fly with caution.
So, the failures all happened pretty quick. Abnormal flight, check. The gimbal was shaking, there was some yaw, some shake and some shimmy and the craft was drifting. I did keep calm and bring the craft back safely - I had LoS and it was only about 800ft away, though I needed the camera to get my bearings. And guess what, all the systems came back online. I landed, took back off and did some flight testing. All seemed well. I landed and called it a day.
My questions:
a) When I saw those compass warnings, would it have been wise to recalibrate?
b) Was the compass failure even related to the warnings?
c) Was the weak GPS signal responsible?
d) Was it expected that the IMU would fail w/o GPS and compass? I understand that a compass failure shuts down the GPS by design, but what about the IMU?
e) Was this just a fluke or does this type of thing happen often?
f) What, if anything, should I do anything before flying again?
Thanks in advance for any insights.
