Experimenter is a magazine created by EAA for people who build airplanes. We will report on amateur-built aircraft as well as ultralights and other light aircraft.
Issue link: http://experimenter.epubxp.com/i/339662
Visit SportAir.org to register today or call 1-800-967-5746 for details. EAA SportAir Workshops are sponsored by Get Hands-on. Get the skills you need from the experts you trust. SportAir Workshops Dates EAA SportAir Workshops Offered Location July 19-20 .................. RV Assembly.................................................... Riverside, CA (Flabob) July 31-August 1 ....... Electrical Systems .......................................................... Oshkosh, WI August 16-17 ............. TIG Welding ......................................................................... Griffin, GA August 23-24 ............. RV Assembly......................................................................... Waco, TX September 6-7 .......... Composite Construction, Fabric Covering, .......................Dallas, TX Sheet Metal, Electrical Systems, & What's Involved in Kit Building September 20-21 ...... Composite Construction, Fabric Covering, ..................... Detroit, MI Sheet Metal, & Electrical Systems EAA Webinars What would you like to learn? Interactive. Educational. Mobile. EAA offers a series of free live webinars moderated and presented by aviation experts on a variety of topics. Register today! EAA.org/webinars EAA Webinars are supported by EAA Experimenter 37 Repeat the test with a little more pedal and stick. Continue this incremental buildup until you've checked the airspeed error for the amount of sideslip you think necessary. If you intend to use full-pedal forward slips, clear the envelope to full-pedal sideslips, if it's safe to do so. If you can achieve all the forward slip benefi t you want with less than full pedal application, you can stop there, but be sure to honor that limit from then on. If you noted an airspeed error as you performed your incremental sideslip increases, apply that error when per- forming your next sideslip. For example, let's say the original trim speed was 65 knots. You performed a half-pedal sideslip while maintaining that 65 knots, but when you returned to balanced flight, the airspeed indicator read 60 knots. If you performed the check correctly, you were actually flying at 60 knots in the sideslip even though the airspeed indicator read 65 knots. Repeat the test by starting at 65 knots in balanced fl ight. As you increase the sideslip, adjust the plane's pitch attitude to maintain 70 knots with half pedal applied. You're really fl ying at 65 knots here. Note: Just because there was a 5-knot error at half pedal, that doesn't mean the error will be the same at full pedal. Continue your testing, making adjustments for the airspeed errors until you've mapped the errors for the various sideslip conditions. Ensure you apply these airspeed correc- tions whenever you perform forward slips. IMP OR TA N T CONSIDER AT IONS There are a few more things to consider before embarking on this test procedure. First, make sure your airplane is structural- ly able to handle whatever sideslips you plan to evaluate. Some airplanes have powerful rudders. You don't want to damage the vertical tail. Ensure there's no prohibition against sideslips in a particular confi guration. Some airplanes have limits on side- slips with the fl aps beyond a certain setting. This may be for structural considerations or due to the fl aps disrupting airfl ow over the vertical tail. If the airplane doesn't feel right as you increase the sideslip, stop and investigate why. Some rumbling, buf eting, and changes in wind noise may be normal, but they could also signal that the plane is approaching an aerodynamic clif . You don't want to stall the vertical tail or precipitate a stall or directional departure. Once you've cleared the sideslip envelope, you can begin exploring your airplane's lateral and directional stability characteristics. Stay tuned. E A A E X P _ J u l y 1 4 . i n d d 3 7 EAAEXP_July14.indd 37 7 / 1 / 1 4 9 : 5 8 A M 7/1/14 9:58 AM