The Cessna 120-140 Association Forum

So a few weeks ago I asked for some advice on setting aileron cable tension and it was suggested to set the carry-through tension at 30# and not worry too much about the "control" cables. I've done that and the control cables are around 22 pounds. Too loose? The manual states the bolts attaching the control cables to the bellcrank and the bellcrank attaching/pivot bolt should all be equal distance from the nearby rib. 2 17/32" - a pretty precise specification. When I get the cable tension as best as I can, the aft (control) cable bolt is ~1/4" too far away and the forward cable attach bolt (the carry-through cable) the same distance too close to the rib. I presume this will put my aileron travel out of specification but I don't know how much yet. How much can the aileron travel be out before I'm being unsafe?

Thanks for everyone's help,
Dave

Are the measurements the same on both sides? Sounds like you need to loosen the carry through cable and tighten the control cables, or vice versa. Rig the bell cranks first then adjust the aileron positions by adjusting the pushrod lengths.

Aileron cable tension is taken on the balance cable only. Tape a straight edge across the yokes to make them even. Adjust the direct and balance cables so the bell-crank is in the neutral position, the balance cable is set at 30 lbs, and the up-stop on one aileron hits it's stop the same time the opposite aileron hits it's down stop. Once the tension and stops are set, then adjust the aileron control rods to fare with the wing. Then double check the control travel up and down. Specs and procedure are in the pilot's operating manual. PS-use .041 SS safety-wire on turn-barrels.

The carry through cable will always have a high tension than the two cables that travel up from the yokes. Probably around 10+ pounds difference.