LIghtweight pure-x racer based on Realacc's QAV-X clone.

Frame

The frame is the 3mm version that is a little bit lighter than the 4mm variant. What i didn't expect is the ammount of flex in the arms. On closer inspection it turns out the weave of the carbon is at a 45° angle to the arm direction and that makes it flex much more than needed. Kabab FPV did some tests with weave direction and it turns out that aligning the weave along the direction of the arm makes it much stiffer. Anyway, live and learn.

Flight Controller

The flight controller is the Omnibus F4 Pro v2. I wanted this one because it has both the betaflight OSD and a current sensor on board. I needed some creative wiring to get the power from the XT60 connector into the flight controller and back into the 4-in-1 ESCs.

This particular flght controller has an onboard LC-filter to provide clean power to your camera and transmitter. The camera and transmitter require 5V and are connected to the output pins of the LC-filter. Although you can bridge two pads and route the 5V from the onboard regulator to the LC-filter, I've opted not to do that because the 5V regulator on the flight controller isn't very powerfull. Instead I opted for a 5V pololu buck converter to supply power to the LC-filter diode directly. Alternatively I could have wired the LC-filter directly to VBat, but the V2 version of this flight controller has a wiring issue where drawing power through the LC-filter directly from VBat will mess with the proper working of the current sensor.