Hello,

Just received my new Phantom 4 V 2.0 after flying my Phantom 3 Advanced for 3 years.  I fully charged everything and updated firmware. Immediately after the first takeoff, I knew something wasn't right. The drone was drifting in the air both horizontally and vertically.  The red indicator in the middle of the app screen was showing numbers of 30-40 ft but I was actually hovering around 10ft from the ground.

I decided to fly the drone normally and while it did ascend very quickly, it would move very slowly on the horizontal axis. Putting in sport mode allowed for much faster movement. However, when it came time to descend from 150ft, the drone was only dropping about 1ft  per second or so with the controller stick fully in descend. After the drone finally made it to about 15ft it suddenly started to rapidly ascend again. I hit RTH and it started to come back and then I got a message saying the drone was 1ft about ground when in fact it was still 50ft or more above ground. This was happening in an open field.

Upon one more attempt to fly the drone, I was experiencing the very slow descend when all of sudden it started dropping rapidly (like what I'm used to on the Phantom 3) and I had to quickly reverse the stick and make the drone climb.

In its current state, this is not a safe and usable drone. Hoping to hear some suggestions.

Hi, do you use a gimbal guard across the 2 legs?

The most likely cause is the VPS.
Do you have the VPS sensors downward view blocled by any "gimbal guard" etc?

First thing to check is to disable the VPS in the app settings and see if that changes anything.
If it works normally with the VPS off, you've identified the issue.
calibrating the VPS may help
https://www.google.com/search?q=phantom+calibrate+the+vps+sensors

Bashy Posted at 2018-7-16 19:37
Hi, do you use a gimbal guard across the 2 legs?

Yes, I do have gimbal guard across the legs.  I'm slightly embarrassed that I didn't think to remove it and try it again. Thanks

No probs, been there, done that....

Hey, at least you don't have a problem. Easy fix. However, made me wonder when you first turned on the P4 and the gimbal did it's calibration was anything damaged trying to rotate?