I just did a quick demo video to show Arducopter 3.0.1 flying a large electric heli. This is my new GreyHawk Maxi development frame. Loosely based on TRex 550 mechanics, stretched to 700 size, and with a direct drive tail rotor motor. The DD Tail gets rid of a lot of unreliable, noisy, vibrating geartrain. The heli is very smooth and you can hear the blades instead of gears screaming. In person, it's actually eerily quiet, if there's a wind out, you can barely hear it from a few hundred feet away.
This video is pretty tame. But I wanted to show how stable the and precise Arducopter can be. Normally I shoot test video in worst-case conditions, but most marketing videos are done to show perfect performance, so here you go.
This is only my 4th flight on this new heli, and I'm still getting it dialed in. Alt Hold has absolutely no problem at all with the Asymmetric rotor blades.
This video is also the first appearance of the DD Motor control feature which should be coming out with 3.1. The motor control for the tail motor comes out of Ch7. The setpoint can be changed in MP, independently of the main motor setpoint. And it can be started before the main motor, or held on after the main motor is off (auto-gyro flight). One very nice feature of this system is that you can have different flight modes on the main rotor, low speed and high speed, but the tail motor retains a set speed, even with a very low main rotor speed, so you retain tail authority.