Engine thrust
 

I bought an electric park flyer from Hobby Lobby called the Leonardo. It flys great, with two exceptions. It tends to nose down when power is removed, and stalls easily at slow speeds. By slow, I mean I've had planes much slower that didn't stall. My CG is dead on to what the factory shows which is about 1/3 the wing chord.
The only thing I notice is that the engine has quite a bit of right thrust, but none down.
Should it have down thrust?
Thanks
Dick

RE: Engine thrust
 

no. the right thrust is to counter the torque effects of the motor. you put downthrust in when your wing has so much lift that it will nose up when it is moving fast, but stay level when there is not enough power for the down thrust to have any effect (like a trainer). i would just move back the cg about an eighth of an inch, and maybe see if you can get it any lighter.

RE: Engine thrust
 

Thanks for the reply, I will give that a try
Dick

RE: Engine thrust
 

Dick:
You need to add downthrust.
Adding downthrust will cause the airplane to pitch down when power is on, so when power is on, you will need to add a bit of up trim to fly level. Keep adding downthrust little by little and retrimming as required until BEHOLD! you will reach a point where you can cut power and the plane will pitch down slightly into a gentle glide.
I would leave the CG at 33 percent, or even move it forward to 30 percent to improve the glide speed and pitch stability for landing.
I would leave the right thrust as is. [sm=sunsmiley.gif]
S

RE: Engine thrust
 

Feihu-RCU
Thanks for the reply. I flew it again today, and still have the same problem (haven't added the downthrust yet. just saw your post)
I raised the trailing edge, but still no luck. The plane is balanced 33%.
I'm going to add downthrust as soon as I'm done typing.
Thanks again.
Dick

RE: Engine thrust
 

Downthrust always when conditions like that!

RE: Engine thrust
 

One other thing might be getting to you. The airplane is really light with a fair amount of drag. Remove power and it just has a bad glide ratio.