AOPA Online Members Only -- AOPA ePilot Flight Training Edition -- Vol. 6, Issue 50

CRITICAL ANGLE OF ATTACK
Pilots learn that a stall can occur "at any airspeed, in any attitude, with any power setting," as explained in Chapter 4 of the FAA's Airplane Flying Handbook. How well do you understand this concept?

The typical method of practicing and demonstrating straight-and-level stalls and recoveries is to slow the aircraft down in the takeoff or departure configuration until it reaches the minimum controllable airspeed (MCA) depicted on the airspeed indicator, inducing the stall, and recovering. (See the February 10, 2006, Training Tips article "Pre-solo Stalls.") This is a safe way to demonstrate the effects of exceeding the critical angle of attack. But letting the discussion end there carries the risk of fixing in a student's mind the inaccurate notion that exceeding that angle of attack can be prevented simply by flying above minimum controllable airspeed (MCA). That's not so.

Suppose you are on your final approach glide with flaps down, throttle at idle, and maintaining an indicated airspeed of 65 knots, well above MCA for your airplane. Another aircraft suddenly appears below and in front of you. Your first reaction is to haul back sharply on the yoke to avoid collision. Without decelerating to MCA, the aircraft wing exceeds its critical angle of attack and stalls-unexpectedly and at low altitude. Because this is a so-called accelerated stall, the added lift induces a load on the airframe. To understand maneuvering speed's importance to stall avoidance, see Rod Machado's "A New Look at Maneuvering Speed" in the March 1999 AOPA Flight Training.

A glance at your pilot's operating handbook reminds you that stall speeds increase with bank angle. Practicing a level-flight steep turn, or increasing bank to complete a turn in the pattern, you are surprised to hear stall-warning activation at what seems to be a healthy airspeed. Remember that you are flying a maneuver with a high-load factor, meaning that the aircraft wing is producing horizontally inclined lift to turn the aircraft plus the necessary vertical component of lift to regulate altitude. It is flying closer to its critical angle of attack than in unaccelerated level flight.

Managing angle of attack at any airspeed, attitude, or power setting is the key, as the opening words above remind us.

As an AOPA member, you also have online access to articles from AOPA's flagship publication, AOPA Pilot magazine. Simply go to the AOPA Pilot archives for a wealth of information, organized by subject. From training information to safety articles, legal issues, aviation careers, and more-take advantage of this additional AOPA membership benefit to get the most out of your training.

Do you have a question? Call the experienced pilots in AOPA's Pilot Information Center at 800/USA-AOPA. They're available to take your calls weekdays 8:30 a.m. to 6 p.m. Eastern. As an AOPA Flight Training member, you have access to all of the features within AOPA Online and AOPA Flight Training Online. Login information is available online.

AMERICAN EAGLE HIRES THREE ATP GRADUATES
Three graduates of Airline Transport Professional's professional pilot program at Daytona Beach, Florida, won interviews and job offers from American Eagle Airlines in November. Under an agreement with American Eagle, ATP graduates can receive job offers with specially reduced minimums. In other news, ATP ordered five ELITE RC-1 advanced aviation training devices equipped with Garmin GNS 430 avionics. "ELITE's RC-1 is the perfect Garmin GNS 430 procedures training platform to complement the other 26 FTDs at ATP's training centers," said Jim Koziarski, vice president of flight operations. For more information, see the Web site.

LIBERTY GETS AUSTRALIAN CERTIFICATION
The two-seat composite Liberty XL2 has expanded its global reach by entering the Australian market. As many U.S. manufacturers are seeing growth in foreign markets, Liberty believes the Australian certification will be "integral to the strategic growth" of the company. Liberty's first Australian delivery will be on display in March at the Australian International Air Show in Melbourne.

GETTING HUNGRY? TRY NEW $100 HAMBURGER WEB SITE
If you and your flight instructor like to check out new places for $100 hamburgers-or if you enjoy spreading the word about good destinations for pilots-a new Web site is looking for you. Brakesoff.com is the creation of AOPA member Alex Hoch, who says he came up with the idea "in a quest to always have something to do while I'm on the road." (Hoch works for a fractional aviation company, so it's likely he's on the road quite a bit.) The Web site includes all public U.S. airports, and all comments on restaurants, FBOs, and area attractions are added by users. It's free, says Hoch, "and always will be."

FIND THE RIGHT WORDS WITH NEW SAFETY SEMINAR
Boost your radio communication knowledge, find out what popular phrase the 2007 Aeronautical Information Manual says should no longer be used under any condition, and learn the three magic words to use when communicating with air traffic control during the AOPA Air Safety Foundation's latest safety seminar, "Say It Right! Radio Communication in Today's Airspace." A local air traffic controller will be at each seminar to host a Q-and-A session, thanks to the National Air Traffic Controllers Association (NATCA). "NATCA is pleased to be working with the AOPA Air Safety Foundation on such an important venture. The foundation's communication seminar offers pilots a wealth of practical information for communicating with air traffic control," said Paul Rinaldi, executive vice president of NATCA. "This is an ideal event for us to learn from one another and help enhance an atmosphere of teamwork and trust." The free seminar will start its national tour in January. To find out when it and other Air Safety Foundation seminars will be in your area, see the Web site.

HAVE YOU UPDATED YOUR AOPA MEMBER PROFILE?
To make the most of your membership and allow us to serve you better, please visit AOPA Online and update your personal member profile.

CORADINE LOGBOOK SOFTWARE INCLUDES 40 HOURS FREE USE
Coradine Aviation Systems, makers of the LogTen Pro version 3.0 software for Macintosh OS X, has changed its "Try Before You Buy" program so that the first 40 hours of logged flight time on the software are free. The company says it's trying to do its part to help reduce the high cost of becoming a pilot. The announcement came in conjunction with the release of the latest version of LogTen Pro. Upgrades and new features for LogTen Pro 3.0 include a flight journal that lets pilots keep a more detailed record of their trips, a resource manager that lets users manage aircraft, airports, people, and certificates; inline totals; and the Smart Group system, which can be used to track currency and duty requirements for pilots operating under any international regulatory criteria. To download the software, see the Web site. If you commit to purchase, the retail price is $89.

Note: Products listed have not been evaluated by ePilot editors unless otherwise noted. AOPA assumes no responsibility for products or services listed or for claims or actions by manufacturers or vendors.

Question: Other than during the night, when is an airport location beacon used?

Answer: The use of a beacon during daylight hours in Class B, C, D, or E surface areas will typically mean ground visibility is less than 3 miles and/or the ceiling is less than 1,000 feet. At many airports a photoelectric cell or clock timer will automatically operate the beacon; however, some airports manually control the beacon through ATC personnel, so the beacon may be on before sunset until after sunrise. There are varying color combinations of beacons to distinguish between different types of airports and heliports. For additional insight review the FAA's advisory circular, AC 150/5345-12E, and "Airport Lights" from the May 1998 Flight Training.

Got a question for our technical services staff? E-mail to [email protected] or call the Pilot Information Center, 800/872-2672. Don't forget the online archive of "Final Exam" questions and answers, searchable by keyword or topic.

To submit an event to the calendar or to search all events visit AOPA Online. For airport details, see AOPA's Airport Directory Online.

FLIGHT INSTRUCTOR REFRESHER CLINICS
The next AOPA Air Safety Foundation Flight Instructor Refresher Clinic is scheduled in Denver, December 16 and 17. Clinics are also scheduled in Long Beach, CA; Portland, OR; and San Antonio, January 6 and 7. For a complete schedule, see AOPA Online. Can't make it in person? Sign up for the CFI Refresher Online.