Training Tip: ‘Drag is free’

Not you, of course. But it’s likely that some of the folks who fly the airplane are being harder on the equipment than necessary. Now the chief instructor has reminded the staff CFIs to bear down on students’ and renters’ braking technique.

When you make a normal landing on a comfortably long runway, the combination of surface friction, aerodynamics, and ultimately, mechanical braking gets you down to taxi speed without using up excessive runway or putting undue stress on the undercarriage.

Evidence of overly aggressive braking is apparent in tire wear or damage. A less obvious source of accelerated wear on landing gear components occurs if pilots fail to let aerodynamics play its natural role in decelerating the aircraft.

Aerodynamic braking—that is, using drag to slow the aircraft after touchdown—is often what is missing from new pilots’ landing technique. Instead of maintaining aft-elevator pressure after touchdown, many pilots let the nose drop to the ground right away, then they jump on the brakes to make the aircraft slow down. For flight instructors, reminding their students to hold the yoke back and let the nosewheel come down naturally during deceleration is a common element of teaching landing technique.

Aerodynamic braking isn’t appropriate for landing at a short field; there’s a specialized method tailored to that scenario. “On the other hand, an ordinary landing roll with considerable excess runway may allow extensive use of aerodynamic drag to minimize wear and tear on the tires and brakes. If aerodynamic drag is sufficient to cause deceleration, it can be used in deference to the brakes in the early stages of the landing roll (i.e., brakes and tires suffer from continuous hard use, but aircraft aerodynamic drag is free and does not wear out with use),” says the Pilot’s Handbook of Aeronautical Knowledge (page 11-16).

Nothing that’s free remains in unlimited supply, and aerodynamic drag is no exception. “The use of aerodynamic drag is applicable only for deceleration to 60 or 70 percent of the touchdown speed,” the Pilot’s Handbook of Aeronautical Knowledge discussion notes.

At lower speed, “aerodynamic drag is so slight as to be of little use”—so act fast while supplies last.

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