Engine thrust
#1
Thread Starter
Senior Member
Joined: Sep 2003
Posts: 101
Likes: 0
Received 0 Likes
on
0 Posts
From: wlocks, CT
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
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
#2
Senior Member
Joined: Apr 2003
Posts: 4,643
Likes: 0
Received 0 Likes
on
0 Posts
From: chatsworth,
CA
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.
#4
Senior Member
Joined: Sep 2002
Posts: 245
Likes: 0
Received 0 Likes
on
0 Posts
From: Sun City,
AZ
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
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
#5
Thread Starter
Senior Member
Joined: Sep 2003
Posts: 101
Likes: 0
Received 0 Likes
on
0 Posts
From: wlocks, CT
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
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
#7
Senior Member
Joined: Oct 2002
Posts: 1,406
Likes: 0
Received 0 Likes
on
0 Posts
From: St. Charles, MO
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.



