Unstable Copter

Hi I’m testing a newly built quad tethered by hand before flying and have noticed a couple of issues:

  1. At the point of liftoff the quad starts to oscillate fairly violently but smooths out if more power is applied and oscillates again on throttle down.
  2. The throttle is very on/off. Drone either rockets up or drops like a stone. I want to be able to sit in the hover zone.

My set up is: 270mm quad
COG sits about 3mm below the prop c/l
FC - Micro APM 2.7.2 Firmware: AC 3.2.1 / AP 3.4.0
Aerostar 30Amp ESC
EMax 2205 2,300kV, 4s
Props: 5" x 3"
Flight Mode: Stabilise
Otherwise most flight settings are default in Mission planner

Any suggestions?
How do I capture a log?

image

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In case another Newbie has this issue, by reducing Roll/Pitch Sensitivity to minimum in Basic Tuning the quad was stable at hover. Its most likely due to the COG being almost in line with the plane of the props. I reduced a few other variable to quieten it down whilst I was there.

image

The throttle issue was because the motors would not power up until 10% throttle so it was difficult to control. I re-calibrated the radio but no luck. So I moved the throttle trim up to take out the ‘freeplay’. Probably not the best solution but the only one I found worked to give me a smooth throttle application.

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You can probably do better than that. Post a link to a .bin flight log file.

Ah, nevermind. I see you have an APM FC. You should replace that.

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