Aero-Tips!

A good pilot is always learning -- how many times have you heard this old standard throughout your flying career? There is no truer statement in all of flying (well, with the possible exception of "there are no old, bold pilots.") It's part of what makes aviation so exciting for all of us... just when you think you've seen it all, along comes a scenario you've never imagined.

Aero-News has called upon the expertise of Thomas P. Turner, master CFI and all-around-good-guy, to bring our readers -- and us -- daily tips to improve our skills as aviators, and as representatives of the flying community. Some of them, you may have heard before... but for each of us, there will also be something we might never have considered before, or something that didn't "stick" the way it should have the first time we memorized it for the practical test.

It is our unabashed goal that "Aero-Tips" will help our readers become better, safer pilots -- as well as introducing our ground-bound readers to the concepts and principles that keep those strange aluminum-and-composite contraptions in the air... and allow them to soar magnificently through it.

Look for our daily Aero-Tips segments, coming each day to you through the Aero-News Network. Suggestions for future Aero-Tips are always welcome, as are additions or discussion of each day's tips. Remember... when it comes to being good pilots, we're all in this together.

Aero-Tips 02.06.06

Remember "overbanking tendency"? Some instructor told you that it takes opposite aileron to hold bank angle in a steep turn. He/she called it the "overbanking tendency" -- the propensity for bank angle to increase in a steep turn.

This is why stable airplanes spiral, and why spirals are a common end to Visual-into-IMC flight.

Trim and Stability

"Stability" measures the tendency to dampen out oscillations (from turbulence or pilot ham-handedness) and return to the original flight condition.

Although a little instability in roll makes for a "sportier" feel, most designers aim for a great deal of stability in pitch. This makes holding airspeed, attitude and altitude easier. The stable airplane adjusts to changes in air flow over the elevator. A trimmed airplane will seek to maintain a constant air flow (indicated airspeed), and when disturbed will adjust attitude to do so.

Example: Trimmed for level flight, reduce power. The airplane slows and air flow over the tail diminishes. The airplane then noses down to regain the trimmed air flow, setting into a constant-speed descent.

..and Overbanking

Now consider the airplane in a steep turn. Beyond about a 35 degree bank the airplane will continue to roll. Say the airplane is allowed to overbank. The wing is lifting "up" relative to the airplane, not the ground, so the nose drops below the horizon. This increases speed and the airplane tries to recover…by pulling the nose "up" relative to the airplane. This only tightens the turn, increasing the bank and airspeed, and inducing even more of a pull "up" as a result of stability. Soon the airplane is accelerating in an ever-increasing rate of descent. It will spiral into the ground, exceed redline speed and break up in flight, or structurally fail if the pilot tries to recover incorrectly.

Fatalities occur when bank exceeds about 35 degrees, and the pilot doesn’t compensate for overbanking -- as often happens in the disorientation of inadvertent instrument flight.

Aero-tip of the day: Understand the roll and pitch characteristics of your airplane, and compensate for overbanking tendency. If the plane begins to spiral, leveling wings is the first step in recovery.

FMI: Aero-Tips