Two issues with Bloody Wonder Wobble and Motor quiting

[Foxbodyford]

Just finished my FT Bloody Wonder build and flew it this weekend. Had my throws a bit too large at first and wasn't so smooth to fly but that was an easy adjustment. The problems that I have are first when flying quickly the tail wobbles side to side. Not a big issue most of the time but it does throw the plane off some.

The real issue is I'm running a Red Brick 50A ESC, D2826-6 2200KV motor on a 3S 1000mah battery. When I run a larger than 6" prop the motor stops at anything above half throttle. One a 6" prop it shuts off at full throttle, and with a 5" prop it flew 2/3rds of a full pack thru before stalling. If I throttle down for a second or two i can throttle back up. I tried running 2 3S 1000 batteries in parallel and was able to run the 6" prop until nearly drained.

Even with these issues I've enjoyed flying the plane.

 

[flyin201]

I think that kv might be a little too high, that motor may be intended for an edf. With the higher load of a bigger prop it probably doesn't have the torque to turn it. I would try a 1200 kv. I have a 2826 motor with a 1200 kv rating and can run up to an 8x6 prop on 3s.

As far as the wobble at high speed I think some of this is unavoidable due to the design of the model. Due to it being short coupled it needs the added directional stability of the twin vertical. This is fine at slower speeds and aids in maneuverability, however a longer tail section is needed at high speeds. If the vertical stabs are out of alignment it will make the wobble worse.

 

[Foxbodyford]

Will try a lower KV motor and check my stabilizers to make sure they are parallel to each other.