How to configure an Octocopter Coaxial frame in Arducopter

ArduCopter
1

Hello,

I would like to build an Octocopter coaxial frame (16 motors, 8 arms, two motors per arm) and I plan to use Arducopter with Mission Planner. I am using Pixhawk 6C, so there are 16 pins on both Main and Aux PWM.

I’m a bit unsure how to set up this geometry in the Arducopter or frame configuration.

  1. Which airframe type should I select, as I can’t find this airframe type?
  2. Any tips or documentation on motor order and rotation direction for coaxial setup?

Thanks in advance for your help!