Dear All,
                I had made a balsa mosel of pusher configuration with the poluhideeral wing span of 1.6m.
I had just done a flight test today and recorded some observations.
1. I did a hand launch , plane dives when throttle is more than 3/4. otherwise it climb up smoothly on less throttle .
2. its gliding is excellent ,  so i can say that C.G. balanced correctly on model.

3. As i increase throttle more than 3/4, i t does a nose dive. Can anyone suggest me what cud be the problem.
I checked the angle of incidence on wing and tail , Tail=0 degree and wing = 2 degree(which gives better results on the earlier made models).
The motor angle is 1degree down. Please suggest what cud be the problem

Thanks in advance.


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  • Glad you had this problem before me. I am about to test fly my 25cc, 2.7m pusher. I was considering the motor incidence and came across all these helpful comments in advance. mm but now what about left and right incidence. with a T tail will the prop wash affect the yaw. and I wonder how much the torque will play into this. any fancy equations someone may have come across that I can work it out. (not too fancy I'm 'van der merwe' not 'einstein')

  • Viky,

    on pusher planes, motor incidence has to be positive !
    Say propeller toward sky.

    Anyway where is motor mounted, in line with fuselage or higher like EZ* etc ? This last one is causing pitch down even more.

    About CG a good glide is not an indicator of right CG. You can try CG playing with throttle while climbing. You can do that watching the behavior in inverted. You can put the plane gliding in a 45° dive; when you center the sticks if it goes straight it is well centered, if it climbs it is nose heavy (yes that's right !) if it dives more it is tail heavy. But remember that all this is related to wing and motor incidence too.

    Best regards,

  • Admin
    Increase the motor angle to 3 and see. Can you share some photos of the airframe? good luck
This reply was deleted.


Shivchand Jaysaval liked Shivchand Jaysaval's profile
Aug 25