AOPA Online Members Only -- AOPA ePilot Custom Content --Vol. 5, Issue 39

The following stories from the September 26, 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 - Piston Single Engine Interest
GET-THERE-ITIS CAN KILL
The determination to reach a destination, combined with hazardous weather, claims the lives of dozens of pilots and their passengers yearly. Sometimes, when pilots are waiting out cloud cover, the fact that it lifts from over the airport can mislead some to assume that conditions would be the same over the surrounding area. Such was the case in the flight of a Cessna 170 on May 17, 2002. Read about what went wrong in this report prepared by the AOPA Air Safety Foundation, exclusively for ePilot readers.

My ePilot - Student Interest, Training Tips
OLLUSION LEADS TO OCCLUSION
Cold fronts, warm fronts, and stationary fronts tend to capture the weather headlines when you're learning to fly, and thorough comprehension of the weather that each can serve up is essential knowledge for a pilot. But there is another kind of frontal weather that can occur when a fast-moving cold front overtakes and runs beneath a preceding warm front. This is an occluded front, and the weather that it produces can be interesting indeed. The National Weather Service defines an occluded front as a "complex frontal system that occurs when a cold front overtakes a warm front. Also known as an occlusion."

An occlusion brings with it both good news and bad news, writes meteorologist Jack Williams in his October 2002 "The Weather Never Sleeps" column, in AOPA Flight Training. "An occluded front is an area where warm, cold, and cool air masses are in conflict and can bring a combination of the kind of weather found in both warm and cold frontal zones. While an occluded front can bring really nasty weather, it's also normally the last stage of a middle latitude storm."

Like other fronts, occlusions are plotted on surface analysis charts and the surface panels of low-level significant weather prognostic charts, using standard symbols found in Section 11 of FAA Advisory Circular 00-45E, Aviation Weather Services ( click here to download). A vector accompanied by a number depicts the direction and speed of frontal movement.

Discuss with your flight instructor the implications you could face any time a front is expected to pass during, or shortly before or after, a planned flight. The August 2002 "Wx Watch" column titled "Frontal Scope-out" in AOPA Pilot gives pointers on how to make a prudent decision, and it provides a "Decoding a Front" table.

AOPA Pilot Editor-at-Large Thomas A. Horne in his January 2000 "Wx Watch" column asks if there is a lack of emphasis on weather knowledge in pilot training-and he challenges pilots to go beyond simple preparation for the Private Pilot Knowledge Test in their study. Being able to interpret the implications of an occluded front in your preflight forecast, after researching the materials suggested here, is one way to meet his challenge.

My ePilot - Training Products
AVIONICS TROUBLESHOOTING GUIDE FROM AEA
Your aircraft's audio panel doesn't seem to be working properly. Is it a malfunction, or did you forget to turn up the volume? Download a free pilot's avionics troubleshooting guide from the Aircraft Electronics Association. It gives general troubleshooting advice as well as specific pointers for navaids (loran, radar, DME, ADF, GPS, and VOR/ILS), transponders, radios/intercoms, and autopilots, and may be downloaded from the AEA Web site. The Pilot's Guide to Avionics, which is basically a directory of AEA member repair stations, manufacturers, and distributors, also has chunks of useful information about how to prolong the life of your avionics equipment and how to safeguard it against theft. See the Web site to request a free copy.

My ePilot - Student Interest, Final Exam
Question: What's the difference between a turn indicator (also called the turn and slip indicator, the turn and bank indicator, or the needle and ball) and a turn coordinator?

Answer: Both instruments are actually two instruments in one, work on similar principles, and offer similar information on direction and rate of turn. Each has a ball whose movement indicates slipping or skidding in a turn. However, the turn indicator's needle shows only rate of turn, while the turn coordinator's miniature airplane shows rate of turn and also rate of roll. Here's an example of their difference: If you are in a slip and one wing is lower than the other, but your heading is straight, the turn indicator's needle will indicate a left or a right bank. The turn coordinator, on the other hand, will "understand" that the heading is straight, and the miniature airplane's wings will remain level. Both instruments will show the ball off to one side. Learn more online in the article "Banking On The Turn Coordinator" from the July 1995 issue of Flight Training magazine.