Are my 60’ Lines Cursed ?

[Robin_Holden]

Good evening from Spofforth , North Yorkshire.
I’ve an odd lines / handle problem. It goes like this.
1. My 60’ lines are exactly the same length.
2. When I connect up to one particular airplane , my handle is in the correct 90 degree position.
3. After take off , to maintain level flight , my handle is in the ‘climbing’ position , with around 30 degrees .

The flaps and elevators are in alignment.
The C of G is spot on.
Any suggestions much appreciated.

[Rusty]

Is the engine thrust line zero degrees?  The engine may have down thrust.

[Ken Culbertson]

You are on page 1 of the trim chart.  Three things that will change that.  Thrust line has down either by down thrust or elevator incidence.  Flaps and elevator are not aligned to produce level flight.  Nose heavy.  You can't do anything about the wing once it is glued in so you can consider the airfoil center line extended to the nose and tail as the center line.

Ken

[Dan McEntee]

Good evening from Spofforth , North Yorkshire.
I’ve an odd lines / handle problem. It goes like this.
1. My 60’ lines are exactly the same length.
2. When I connect up to one particular airplane , my handle is in the correct 90 degree position.
3. After take off , to maintain level flight , my handle is in the ‘climbing’ position , with around 30 degrees .

The flaps and elevators are in alignment.
The C of G is spot on.
Any suggestions much appreciated.

    If you have someone hold the airplane, pull some tension on the lines, and check the neutral position, is your handle still vertical or is it in the "up" position? If your handle is a cable type that can be adjusted, reset it so that the handle is vertical, and they recheck for neutral. Wiggle the handle up and down several times and go back to neutral and recheck it. If things look good, like elevator/flaps are neutral and handle is vertical, does the elevator and flaps have equal movement up and down? If they do, take a short test flight and see if anything changes under flight load. If not, you may have a pushrod that needs the length adjusted to get thing even both ways. If you have a hard point handle that can not be adjusted, then you will need to make custom attachment clips of varying lengths to even things out. One place to start with, is the flap pushrod from the bell crank to the flap horn, and see if the travel is equal in both directions, and if possible check that the bell crank is in a neutral position.  Then move back to the flap/elevator pushrod. Also, check the location of any control horns if they are the bolt on type, to make sure that the pushrod pivot hole is in line with the surface hinge line. If it is off forward or rearward, that greatly affects things. Is the airplane a profile or full fuselage? Most of this is easier done on a profile.
  Type at you later,
  Dan  McEntee

[Gary Dowler]

Try this.    Take two  strips of wood, sandwich your H stab/elevator between them and clamp them together.  Youve locked your elevator in 0 deg.  Are you flaps also at 0 deg?   Hook up your lines and handle.  Have someone hold the handle ay 90 deg and look at the flaps again.  Are they still at 0, or are they up some?  If they are up some like this, then in flight they are trying to push the nose down, which you are countering with up elevator.

If all is good here, then your engine may be pointing a couple degrees down pulling it nose down, which requires up elevator to overcome.  It pretty much has to be one of these things IF your lines and leadouts are the exact same length.

Gary

[Howard Rush]

First you could see if your lines are cursed, either by interchanging them and seeing if the plane goes the same way or the other way, or by attaching the airplane end of both lines to a fence post and pulling on the handle.