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 better pilots, we're all in this together.

Aero-Tips 05.24.06

Yesterday we looked at the familiar two-bar VASI, or Visual Approach Slope Indicator. At some air carrier airports you may see a variation called the three-bar VASI.

The High and the Mighty

Three-bar VASI installations provide two visual glide paths. The lower glide path is provided by the near and middle bars and is normally set at three degrees while the upper glide path, provided by the middle and far bars, is normally 1/4 degree higher. This higher glide path is intended for use only by high-cockpit aircraft to provide a sufficient threshold crossing height—crews flying mighty 747s and other airplanes with the flight deck high on an upper level of the aircraft are far enough above the landing gear that they need a different visual reference to fly the same glide path.

Although normal glide path angles are three degrees, angles at some locations may be as high as 4.5 degrees to give proper obstacle clearance. VASI angles in excess of 3.5 degrees may cause an increase in runway length required for landing and rollout. See the Airport/Facility Directory to learn the visual glide path angle for your arrival runway.

Be the beam

Whether flying a two-bar or three-bar VASI, or any other visual glide path indicator, FAR 91.129 states: "An airplane approaching to land on a runway served by a visual approach slope indicator shall maintain an altitude at or above the glide slope until a lower altitude is necessary for a safe landing." This does "not prohibit normal bracketing maneuvers... conducted for the purpose of remaining on the glide slope." Although FAR 91.129 applies only to operations at Class D (tower-controlled) airports, it's sound advice any time VASI guidance exists for your landing runway.

Aero-tip of the day: Understand and use the unique presentation of the three-bar VASI.

FMI: Aero-Tips