I have a PV2+ V3. I have the new 2.1 ESC. The 3.08 firmware. When trying to take off Phantom will just spin real fast but never lift off. I have tried several batteries that all check good, recalibrated IMU, set remote to mode 2 where left stick is throttle up. Have the DJI 9450 Props. not the knock offs. I get green lights flashing for take off. I have had a FC40 before this one so I know how to, calibrate do compass ect. I was not connected to vision app but did not think I had to just to take off and fly. I did NOT have range extender on as I just wanted to take off and fly with no video so don't know if I need to do that? I did not upgrade firmware after putting on the 2.1 ESCs but I already had the 3.08 firmware and keep hearing bad things as people move up to 3.12. I bought this used with a bad motor and just change out all the 2.0 ESCs to 2.1 at the same time I put on a new motor. So I never saw it fly before I bought it. All things seem to work Its just that it won't take off, just spins fast but no lift. UPDATE: I went ahead and updated to 3.12 firmware and then re-calibrated the remote control with the RC assistant and the vision 2 assistant 3.8. Put the RC in mode 2 where left stick is throttle up. Still not taking off. Turned off GPS mode, still no take off. I am a few miles from airport so maybe it thought I was in a 'no fly zone'. So I drove about 20 miles out and still did same thing. I had someone hold in air and it blows a lot of wind but not trying to move up. If I try to turn left or right it will pull left or right like it would if it was flying and trying to turn but just has no upward thrust.