Have a 60 size ARF Pico Wacos that keeps going up ...... even with full down elevator. CG is right - Stabilizer does not seems to be level ???? Could this be the cause???

Could your engine thrust angle be off?

I am not sure ..... What would a corrective action be ....... Down thrust or up thrust ???????

If you have too much upthrust, which is one guess for this problem, you would angle the engine downard relative to the line of flight. THis is accomplished very easily with a washer or two in between the firewall and the engine mount. For downthrust, install washers behind the upper two engine mounts. Add more washers for more downthrust.

How is the incidence on the wings? Is it way off?

wing incidence would be my guess . does it change with throttle settings ?

Lower wing is 0 and top wing is +2 degrees ........... At slower speed it does not raise as fast

How far off is the horizontal stab? That little bit of diff in the wings could be some, stab off could be more, neg incidence in the engine could be more. All added up could pose a problem.

there was a post before on this same bird, seems that the struts that hold the top wing are not marked well and can be put on backwards causing the incidence of the top wing to be off enough to cause a drastic climb. do a search on waco and you should find it.


Miloh.