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.")

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. 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.

Look for our daily Aero-Tips segments, coming each day to you through the Aero-News Network.

Aero-Tips 09.13.06

There's a distinct difference between flight visibility and ground visibility. Knowing the distinction helps you safely (and legally) maneuver an aircraft when the visibility is poor but not below required minimums.

Visibility itself has different meanings in daytime and at night:

• During daytime visibility is determined by the distance where prominent unlighted objects are visible…whether you can you see the water tower, for instance.
• At night visibility means the distance a prominent lighted object can be seen. Can you see the beacon atop the water tower, for example.

Note: this means that all else being equal, by definition visibility will actually improve after night falls.

Further, the definition of visibility is dependent on who is making the observation.

• Flight visibility is determined by the pilot, and is defined as the visibility (using day or night criteria) forward from the cockpit of an aircraft in flight.
• Ground visibility is as noted by an accredited ground observer (for instance, a trained air traffic controller), and means the (day or night) visibility reported from the ground.

In most cases the legality of visual flight (or minimums in the case of instrument approaches and departures) is flight visibility as reported by the pilot. It's wise, however, to very carefully approach any situation where ground visibility is reported to be substantially different than what you think you see from the cockpit.

Aero-tip of the day: Understand how visibility is defined, day and night, in the air and on the ground, and use an honest appraisal of flight visibility in those instances where you are given the authority to do so.

FMI: Aero-Tips