Question on flight using Q_Assist

Hello VTOL gurus, I have a little question on Q_Assist mode, hoping for some guidance. I was recently playing around with it on one of my experimental VTOL platforms and I find it a bit strange in that one can’t fly in a “forward and down” trajectory whilst the rotors are assisting with lift/stability.

It seems that the only way to descend is to throttle back and come down in a level attitude, ie. using the rotors to gently lower the aircraft. Is that what others also experience in this mode? It may well be that this is intended for some good reason, but I would also like the ability to pitch down and accelerate forwards in order to transition, ie. not just relying on the forward motor to accelerate in a level attitude.

I hope that makes sense?

For anyone interested, here’s some recent air-to-air porn with my trusty platform, now in it’s 6th year as a quadplane!


Hi Jacques,

Yes, this is true because you are still in a forward flight mode. When the pusher motor burned out on my mini Talon quadplane, the plane went from flying to just sitting in the air. It took me a moment to realize that the Q_ASSIST_SPEED had kicked in to save the plane. I simply changed to QSTABILIZE mode and brought it home.

Now, for normal use, the Q_ASSIST_SPEED usually only kicks in when needed like during a momentary stall. It will lift your wing back up, keep you flying, and shut off.

When the VTOL is “out there” hovering, but you can still see it, I prefer to use QSTABILIZE mode over QLOITER because I have more control with the sticks. Sometimes, QHOVER mode is ok if I want to leave the height alone, but, often during a retrieval, I want the plane descending while moving forward at a faster pace.

Nice video! It’s amazing just how old some of our VTOLs are getting.


Hi Greg, thanks for chiming in, always good to hear your view. I suppose it makes sense to have that behaviour during VTOL assisted flight, after all, it’s really meant to save an aircraft from stall, etc. Unfortunately it does preclude using Quadplane firmware for a whacky idea that have, but more on that later!