S-Tecs Roll Steering
[IMGCAP(1)]Since the invention of the wing leveler, most of the roll control done by general aviation autopilots was either wings level for heading hold or heading command. We didnt use the VOR or NAV modes very much.
The reason is simple. They didnt work very well. VOR signals arent straight but scallop and snake slightly through the ether. Even the best VOR receivers werent all that accurate, although the newer digital models may be. The result was that when needle tracking, the airplane would occasionally dip a wing if not roll into an impressive automatic Dutch roll. After we discovered with loran, if the avionics shop connected the CDI to the box, most pilots still didnt use na…