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Greyhead · 28-03-2005

One useful tip for closed loop or pull / pull systems is to incorporate the Ackerman Principle ( a Google search will explain it fully). Basically make the connections to the control horn slightly behind the hinge line (towards the TE). If the cables are set with no slop at neutral then as the controls are moved the pull side moves slightly more than the other, the "non-pull" cable goes slightly slack, therefore ensuring that there is no undue force on the servo bearing. I’ve used this principle on all my models with no problems; it may not be acceptable to the out and out aerobatic pilots as it is in effect introducing very slight slop into the system, but for all others it certainly is the way to do it.

28-03-2005	#3 (permalink)
Greyhead Scale Model Member Join Date: Oct 2004 Location: County Durham Real Name: Grahame My Models: Preference for biplanes Visit Greyhead's Gallery Posts: 587 Images: 652	The Ackerman Principle One useful tip for closed loop or pull / pull systems is to incorporate the Ackerman Principle ( a Google search will explain it fully). Basically make the connections to the control horn slightly behind the hinge line (towards the TE). If the cables are set with no slop at neutral then as the controls are moved the pull side moves slightly more than the other, the "non-pull" cable goes slightly slack, therefore ensuring that there is no undue force on the servo bearing. I’ve used this principle on all my models with no problems; it may not be acceptable to the out and out aerobatic pilots as it is in effect introducing very slight slop into the system, but for all others it certainly is the way to do it. Last edited by Greyhead; 28-03-2005 at 03:12..