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The Reason Whya few seconds if there’s another pilot facing me across the runway entrance, so he won’t be blinded while I swing into position.The point is not to belittle strict adherence to procedures. Rather, it is to go beyond adherence to understand the reason behind the procedure. You’ve possibly been taught to tap brakes before raising the landing gear, assuring that the rapidly spinning tire won’t “grow” enough to rub as it nestles into the wheel well. If the gear has accumulated a coating of slush in taxi and during the takeoff roll, however, maybe it would be wiser to leave the brakes alone and let the wheels dangle in the breeze for a few seconds to dry off the slush before retraction.A controls check before departure is a normal part of every pretakeoff checklist. The reason why is not just to make sure the yoke moves freely. The check should also require a visual look at the wing (and tail, if visible) to see that the control surface follows the pilot’s input. Employ a shadow’s movement if the sun angle is suitable. There’s a supposedly-true story of a newly- delivered cabin-class twin that was being given a maintenance check for rigging; it was discovered that the rudder had never been connected at the factory. No one had bothered to verify its movement, during several flights. An extreme case, to be sure, but the point is to verify response, not just yoke action.When Procedure Isn’t EnoughA number of years ago, back in 1982, a Boeing 737 was flown into a bridge structure during departure from Washington National airport, not because there wasn’t enough power available to make the airplane climb, but because the power wasn’t applied. The manual takeoff power setting was performed by establishing a specified indication of exhaust pressure ratio, but the engine sensors were iced over and gave a wrong reading. The pilotsBy LeRoy CookWhen reviewing and polishingthe techniques and skills offlying, we often lose sight of the reason behind our pursuit of excellence. The goal is NOT to become as good as we can possibly be at performing a maneuver. Rather, it should be to understand WHY the maneuver is important. That is the element that generates our realmotivation to improve.Consider the obsession with tracking the centerline of a taxiway or runway. Is it simply to perfect our steering technique? No; the line is painted there for a reason, and we’re following it precisely for that reason. It’s there because, if our nosewheel is on the taxiway’s centerstripe, we know that the aircraft parking spots, pavement edges and buildings were laid out to provide specified clearance from the taxiway’s center. Our wingtips are therefore guaranteed safe passage. Stray, and all bets are off.Armed with this knowledge of the reason WHY, we can judge when a deviation from strict adherence to the stripe is acceptable. If a fuel truck or another aircraft has been parked out of position, we should not blithely drive our airplane into it, just to stay on the line; we obviously need to see the danger, determine if our general-aviation wings are short enough to allow swinging over to avoid the obstacle, and thereby prevent the hit. Or, if there are centerline lights or reflectors that create an annoying thump as our small nose tire passes over each impediment, we can taxi more smoothly by offsetting our path by just twelve inches. We know WHY we’re supposed to follow the line, not just that we’re supposed to do it.Runway centerlines, on the other hand, are there not just to14 • TWIN & TURBINEkeep us from running off the edge of the pavement, but to provide a tracking target during the furious run toward liftoff, and during and after touchdown. This becomes particularly important in low- visibility conditions and with a crosswind’s influence. If we tolerate deviation in routine operation, our skill may not be there when we’re challenged on a dark and stormy night. That’s WHY we stick to the centerline, every time we’re using the runway.Do It For A ReasonSlavish procedural observance without an understanding of why we do it leads to rigid piloting— arguably, not piloting at all. At some point in your career, you’re going to encounter a situation that isn’t in the normal or emergency checklist. You need to understand WHY the systems are operated as they are, in order to cope with an abnormality. The pre-takeoff checklist may include a switch position for a piece of avionics or aircraft gear; you should know why that switch has to be on, not just that it’s on the list of things to be done. Is it turning on a pump that backs up a normally-active one, or is it merely an “armed” setting? Is the “ignition” switch doing its job of igniting, or just clicking into position? Can it be verified, audibly or by indication?Turning on exterior lighting when pulling into position for takeoff is not just a checklist item. The reason WHY is important; it’s done so that our aircraft will stand out from the sea of lights in the threshold environment, in case another airplane is heading for the wrong runway or ATC is unsure of our location. Because I know the reason, I understand that I can defer the “light ‘em up” action forOCTOBER 2016