AOPA Online Members Only -- AOPA ePilot Custom Content --Vol. 5, Issue 37

The following stories from the September 12, 2003, edition of AOPA ePilot were provided to AOPA members who expressed an interest in the particular subject areas. Any AOPA member can receive information customized to their areas of interest by updating their member record file online.

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My ePilot - Instrument Interest
HOW TO BALANCE THE JUGGLING ACT
Flying solely by reference to instruments calls for a high level of skill. Just flying VFR requires the pilot to juggle many different things, but when flying IFR, the juggling act heats up. Read "Balancing the Juggling Act," the first of our 12-part "Instrument Insights" series originally published during 1998 in AOPA Pilot. The series will help you to become a better instrument pilot, no matter what stage you're at. See AOPA Online.

My ePilot - Student Interest, Training Tips
A RIVER (OF FAST-FLOWING AIR)
Whenever you hear the term "jet stream" during a weather briefing, pay close attention. Chances are that the information you are about to receive will be very interesting.

What are jet streams? Here's the National Weather Service's definition: "Relatively strong winds concentrated in a narrow stream in the atmosphere, normally referring to horizontal, high-altitude winds. The position and orientation of jet streams vary from day to day. General weather patterns (hot/cold, wet/dry) are related closely to the position, strength and orientation of the jet stream (or jet streams). A jet stream at low levels is known as a low-level jet."

Not long from now, the presence of a jet stream may start to figure prominently in forecasts of interest to pilots of light aircraft. What starts the ball rolling is the increased contrast in air temperatures as northern latitudes begin to cool down. "As fall turns into winter, upper-air winds begin growing stronger and the jet stream begins to migrate south" following zones of greatest temperature contrast, explains meteorologist Jack Williams in his column "The Weather Never Sleeps" in the December 2001 AOPA Flight Training. Study the illustrated example presented in the article. Note that "in this case, the air could be coming all the way from the Arctic to smash into much warmer, humid air over the South and East. Winds will be strong at the upper altitudes and on the surface. Depending on the temperatures and where you are, rain, snow, and ice could be widespread."

Low-level jet streams may influence weather in summer and at night-perhaps on a calm evening when you least expect it. "Running into a 60-knot wind only 300 feet above ground level after calm surface winds lulled you into being relaxed could lead to more excitement than you really wanted," says Williams in his April 2001 AOPA Flight Training weather column.

Jet streams are also implicated in the presence of such phenomena as clear air turbulence, as explained in the FAA's Advisory Circular 00-30B Atmospheric Turbulence Avoidance. Click here to download it from AOPA Online. Also see answers to questions frequently asked of meteorologists from Meteorlogix, which provides weather to the Web site, for a discussion of the relationship between jet streams and pressure center movement.

Jet streams are of interest to all pilots, in all seasons, not just to jet pilots who regularly operate in the flight levels. As usual in flying, forewarned is forearmed!

My ePilot - Training Products
WIZWHEEL CG CALCULATOR FROM SPORTY's
Figuring out your airplane's weight and balance with fuel and passengers is a good practice for each and every flight. The WizWheel center of gravity calculator looks like an E6B but allows the pilot to quickly determine an aircraft's center of gravity based on an index created for a specific aircraft calculated from its empty weight and arm. The device is simple to understand and could be handy for the pilot who often flies the same aircraft-such as a given trainer at a flight school. It's available from Sporty's Pilot Shop for aircraft including the Beech A36, A36TC, B36TC, 58 and 58A; Cessna 172A through S, 182A through S, 310Q Turbo; Mooney M20C through F, and J through L; and Piper Archer, Warrior, Aztec, and Apache. The WizWheel retails for $49.95. Order online from Sporty's.

My ePilot - Student Interest, Final Exam
Question: I've heard folks at the FBO talk about "through-the-fence" operations. Can you explain to me what that term means?

Answer: The owner of a public airport sometimes allows independent operators (either businesses or individuals) offering an aviation activity to conduct their business on airport property without renting business space at the airport. This arrangement is called a "through-the-fence" operation. Common types of through-the-fence arrangements are for freelance flight instruction or aircraft maintenance. AOPA Online offers additional information on through-the-fence operations.