Nimbus VTOL Questions from a VTOL Noob

Hi All,

This is my first post here, I have used Ardupilot in both fixed wing and multicopter so not a total noob but my knowledge is limited so please go easy on me :smile:

I have built up a Nimbus VTOL and got to the point that I am able to hover in Qloiter and Qhover. My concern is that I have to use way more throttle command then I have ever had to in previous multicopters. I am currently hovering head height at about 80 - 90% stick command on the radio. during bench testing I have noticed that when I then flick over to any plane modes my throttle goes hell for leather. this has left me way to concerned to try a transition in the air.

To confirm my concerns I have a friend that has purchased a “ready to fly” Nimbus direct from foxtech. This was apparently test flown twice already by foxtech. When he received it he did the basic config and calibration required to fly (gps Calibration accel calibration etc etc etc) off he went to maiden. Hover was nice and stable but being new to this he didn’t fully realise that he too was hovering at a very high throttle command. considering the VTOL was stable he ascended to approximately 90m still stable he attempted a transition , when he did this the Nimbus throttled to almost full power and did a backflip. obviously gaining enough airspeed in the flip the VTOL Transitioned to plane as it was meant to but it was too late and the plane was in a difficult orientation resulting in a fatal plummet to the ground.

Is this throttle behaviour common?
Is there a way to tame the throttle conversion from Qplane to plane during transition?
Is there anyway I can test this before I maiden a transition?

I really don’t want to destroy my VTOL on its first flight that I have spent the last 6 months building and tuning.

Thanks in advance I appreciate any helpful advice



Hi Chris,

your friend should look in the logfile, if he directly switched from a Q-mode to manual mode ? That’s what makes a flipback.

Regards Rolf

Thanks I will ask him to send.

So for now I shouldn’t be too concerned about mine as long as I remove manual from all modes to avoid a mistake?

You might want to check out Eosbandi’s and Greg Covey’s build log for guidance.

Good luck.

Thanks for the advice. I seem to remember stumbling across their threads during my build process but will go back and read again for sure

Much appreciated