MA2 flying at angle, not straight

[macfawlty]

On my 3rd battery today, I launched my MA2, flew about 100 yds and noticed it was flying at least 30 degrees off line with forward input only. Bringing it back to launch was challenging as I had to compensate for the off-angle direction of flight. I didn’t use the RTH, which would have been unpredictable. Once I got it overhead, it didn’t move off line or rotate on descent.

Not sure what caused it and didn’t want to tempt fate with another flight from my location on a rock island in the middle of the river with trees around and retrieval unlikely. No problems with the first 2 batteries. I’d just tested the PhantomRain rescue jacket with the 3rd battery on a simple water landing and launch, straight up. I landed, removed the rescue jacket and relaunched on the same 3rd battery. I inspected the arms after landing and they appeared to be fully extended, but in the video clips, I can sorta see the left prop at gimbal level position, FWIW.

Because I only went straight up and down with the rescue jacket on, don’t know if the problem preceded its removal. Could it have been an issue with the battery as one of my batteries was submerged a few weeks ago and I forgot to mark it, so not sure which one was potentially compromised? I’ll mark the 3rd battery I used today as suspect.
What calibration adjustments should I perform to rule that out as a factor? It seems most likely the left front arm may not have been fully extended after removing the rescue jacket although that didn’t seem the case on inspection.

 

[boblui]

Arms not being fully extended should not cause the behavior you have described. The only sensible reason I can think of is the existence of yaw error which is likely caused by the craft being powered on at a location with magnetic interference. You can check by pointing the craft to a landmark that can easily be seen on the map and see if the arrow representing the craft is pointing to the same direction on the map.

Its lucky that the yaw error was not large ( 30 degrees ) or the craft could have flown away by itself.

This is just my guess of course. If you can post the .DAT file of the flight in the phone , the reason can be identified with much better confidence.

 

[DanMan32]

Battery can't affect the direction the drone flies (other than down if loss of power), so that's not the issue.

Was it turning (yaw) where if flying straight it would fly in a (possibly wide) circle, or slipping 30 degrees but otherwise flying straight? IMU or compass issues usually result in constant yaw.

I would consider IMU, compass and RC stick calibration. If it's slipping, I would suspect the RC is registering the right stick being a bit to the right, though it is centered. Be sure you yourself is not accidentally applying a bit of right to right stick as you push it up to go forward.

 

[RobW01]

Gimbal not centered?