# Offset center of gravity

**URL:** <https://discuss.px4.io/t/offset-center-of-gravity/16717>\
**Category:** PX4 Autopilot\
**Created:** [May 13, 2020, 2:46pm UTC](https://discuss.px4.io/t/offset-center-of-gravity/16717 "2020-05-13T14:46:03Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Mohibb](https://discuss.px4.io/user_avatar/discuss.px4.io/mohibb/32/5800_2.png) [@Mohibb](https://discuss.px4.io/u/Mohibb)\
**Post date:** [May 13, 2020, 2:46pm UTC](https://discuss.px4.io/t/offset-center-of-gravity/16717/1 "2020-05-13T14:46:03Z")

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Hi,

I am working on a large multicopter (~20-25 kg, Y6 config), and keep running into an issue regarding the center of gravity. When I am in the air, it flies fine, but during takeoff it leans forward. It fixes itself if I give it a few seconds, but that is not something I can do.

I am guessing that the CG is too far forward compared to where it should be, but this is not something that can be changed.

Is there a way to input the distance between “optimal CG” and actual CG? Like I said, this is only a problem during takeoff.

Edit: I am running on v1.10.1 if that is important

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**Author:** ![bresch](https://discuss.px4.io/user_avatar/discuss.px4.io/bresch/32/2343_2.png) [@bresch](https://discuss.px4.io/u/bresch)\
**Post date:** [May 13, 2020, 3:14pm UTC](https://discuss.px4.io/t/offset-center-of-gravity/16717/2 "2020-05-13T15:14:46Z")

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Hi @Mohibb , you need to adjust the location of rotors relative to the CG in the mixer directly.

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<div class="post-metadata">

**Author:** ![Mohibb](https://discuss.px4.io/user_avatar/discuss.px4.io/mohibb/32/5800_2.png) [@Mohibb](https://discuss.px4.io/u/Mohibb)\
**Post date:** [May 25, 2020, 8:39am UTC](https://discuss.px4.io/t/offset-center-of-gravity/16717/3 "2020-05-25T08:39:49Z")

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Thank you. I have never done anything to the mixers before. Do you have any pointers on where to get started?

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**Author:** ![bresch](https://discuss.px4.io/user_avatar/discuss.px4.io/bresch/32/2343_2.png) [@bresch](https://discuss.px4.io/u/bresch)\
**Post date:** [May 25, 2020, 11:36am UTC](https://discuss.px4.io/t/offset-center-of-gravity/16717/4 "2020-05-25T11:36:29Z")

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@Mohibb Here is the descriptor for your hexa coax mixer: [https://github.com/PX4/Firmware/blob/master/src/lib/mixer/MultirotorMixer/geometries/hex\_cox.toml](https://github.com/PX4/Firmware/blob/master/src/lib/mixer/MultirotorMixer/geometries/hex_cox.toml)  
You can adjust the distances of the rotors to the CG.