One the things every primary student learns somewhere along the way to their certificate is the difference between primary and secondary flight controls. Distinguishing between them isn’t hard: The primary flight controls are ailerons/spoilers for roll, an elevator/stabilator/canard for pitch and some kind of rudder for yaw. Those are the controls we regularly manipulate to put the airplane where we want it to be.
It’s easy to simply toss every other control system available to the pilot into a big basket labeled “secondary.” And it’s not inaccurate. We’re talking, of course, about systems like wing flaps and trim, perhaps spoilers and perhaps some kind of leading-edge device, though both of the latter are relatively uncommon in the fleet as a whole. Labeling these controls as secondary doesn’t mean they’re harmless: When they fail, they can create their own mischief, and this will serve as your regular reminder that there’s no substitute for thorough systems knowledge of anything you fly.
