Some Weight In The Back?

You shouldnt have gotten through private pilot ground school without understanding that, for the same power and weight, minimizing drag will result in an increased airspeed. A gross example might be the difference in airspeed with flaps extended at, say, 55-percent power and when theyre retracted. Of course, no one cruises with flaps extended, but you may inadvertently be adding to the airplanes total drag in cruise when you load it.

Joseph E. (Jeb) Burnside

Tuesday, July 21, 2015 at 12:00 AM ET

Verified

Key Takeaways:

Minimizing drag, particularly from the elevator/stabilator and the horizontal tail's downforce, is key to increasing an airplane's airspeed.
This drag can be reduced by strategically shifting the aircraft's center of gravity (CG) aft, closer to the center of lift (CL), to decrease the required tail downforce.
An aft CG configuration can yield a couple of extra knots in cruise speed due to reduced drag, but it also results in decreased pitch stability.
Pilots must always operate within approved CG limits and consider the trade-offs between speed benefits and reduced stability when adjusting aircraft loading.

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You shouldn’t have gotten through private pilot ground school without understanding that, for the same power and weight, minimizing drag will result in an increased airspeed. A gross example might be the difference in airspeed with flaps extended at, say, 55-percent power and when they’re retracted. Of course, no one cruises with flaps extended, but you may inadvertently be adding to the airplane’s total drag in cruise when you load it.

In a conventional airplane, i.e., one lacking a canard, minimizing the elevator/stabilator’s deflection in cruise reduces drag and can buy you a couple of knots, depending. (The same basic dynamic exists when flying something with a canard—minimize the pitch-control surface’s drag and you’ll fly faster—but we want to talk about what most of us fly.) How much weight to place aft and thereby minimize elevator/stabilator deflection depends on the airplane and how other items are loaded, of course, and you must always stay within CG limits. But if you can easily and safety manipulate your CG, you can go faster.