Kappie Posted March 8, 2012 Share Posted March 8, 2012 Hi All you clever people...I have just finished an Foam Ultimate and set all up as to the manual. The CoG is ever so slightly forward. Took it for it 's maiden yesterday, but had to feed in a lot of "down elevator" for level flight. with all surfaces perfectly level, the plane is nosing up all the time. What have I done wrong/am I doing wrong? Any advise??? Quote Link to comment Share on other sites More sharing options...
ken anderson. Posted March 8, 2012 Share Posted March 8, 2012 kappie - i wouldn't have thought you have done anything wrong.....try adding weight to the nose ..... have a flight and see what the difference is.....by doing so and adding/taking off small bits you should be able to see the difference......and hopefully get rid of the unwanted elevator...normally the recommended c of g is a safe position - so dont be afraid to change it slightly..... ken anderson ne..1 ....c of g dept. Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted March 8, 2012 Share Posted March 8, 2012 Kappie is it pitching nose up with power off and with power on? Or just with power on? Quote Link to comment Share on other sites More sharing options...
Kappie Posted March 8, 2012 Author Share Posted March 8, 2012 Thanks Ken. I have already moved the battery as far forward as possible, but nothing changes. Chris. When taking off -- as soon as the plane leaves the ground it pitches nose up severe, when i cut the throttle it goes nose down again --- it is like a see-saw effect: throttle up = nose up; throttle cut = nose down..... Quote Link to comment Share on other sites More sharing options...
Jimbo565 Posted March 8, 2012 Share Posted March 8, 2012 Could it be possible that the motor has a tad of up thrust built in or may be a wing incidence problem ?? Quote Link to comment Share on other sites More sharing options...
Chris Bott - Moderator Posted March 8, 2012 Share Posted March 8, 2012 Posted by Kappie on 08/03/2012 10:07:26: Thanks Ken. I have already moved the battery as far forward as possible, but nothing changes. Chris. When taking off -- as soon as the plane leaves the ground it pitches nose up severe, when i cut the throttle it goes nose down again --- it is like a see-saw effect: throttle up = nose up; throttle cut = nose down..... Sound very much like a thrust line problem Kappie As it's a foamie, it just worth a check to see that the motor mount is nice and rigid. i.e. that the motor cant move which way it's pointing. But the real issue sounds like it has up thrust as Jim says, or not enough down thrust. Somehow you need to pack out the motor mount, maybe with washers, so that the motor points downward a few degrees. Quote Link to comment Share on other sites More sharing options...
Martyn K Posted March 8, 2012 Share Posted March 8, 2012 It sounds like it needs a few degrees of downthrust. Try about 3 degrees to start with if it is that severe, you may need more. Martyn Quote Link to comment Share on other sites More sharing options...
Kappie Posted March 8, 2012 Author Share Posted March 8, 2012 Thank you all, Gentlemen. I will have a go at it and let you know what the result is. Cheers Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.