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/96284
The barometric pressure can change between your weather brief and arrival at the course, so keep your eyes on the terrain as you approach your test altitude. If it looks like you're too low, raise your test altitude to a more comfortable height. Maintain your altitude throughout the test run. Because you were already established "on condition" before the run began, there should be no need to make power or trim adjustments. Steady is essential. Have the airplane stabilized in the test configuration at the test airspeed in level flight at the test altitude on the correct heading with the power set before passing the start checkpoint. Record your configuration, pressure altitude, observed airspeed, outside air temperature (OAT), and run direction before you pass the start checkpoint. Include altitude, airspeed, and OAT in your scan during the run, and update your recorded data if necessary after the test run. (Figure 1 shows a sample data card.) These parameters should not change, and recording them when established for the test run but before the start checkpoint frees you to concentrate on steady flying with a diligent outside scan. This is a risky flight environment, so stack the safety deck in your favor. Rather than writing your data on a kneeboard, consider using a portable voice recorder (properly secured with wires safely routed) or transmitting your data to someone on the ground to record. If you've accomplished your FAA-required fly-off, a copilot can record the data you call out over the intercom. A second crewmember can provide another set of eyes for monitoring altitude, keeping an eye on the engine instruments, and watching for birds. Now that I've suggested an onboard human data recorder, let me discourage this idea. Test flights can be risky, and the minimum flight crew essential to the flight test or safety is prudent. Both of you must decide whether the benefits outweigh the risks. Begin your timing as you pass the start checkpoint. Call "hack" into your recorder or transmitter or say it over the intercom for your copilot to operate the stopwatch. Your hands should remain on the stick and throttle. Maintain your altitude throughout the test run. Because you were already established "on condition" before the run began, there should be no need to make power or trim adjustments. If the airspeed changes during the run, scratch that run and try it again. Use the horizon as a pitch attitude indicator to avoid chasing an artificial horizon, vertical speed indicator, or any other flight instrument. Keep your eyes outside the cockpit as much as possible. Upon passing your end checkpoint, stop your timing. Make a qualitative assessment of the run you just performed. If the airspeed varied or you made aggressive control inputs or the heading wandered, consider not counting that run, and start again with the reciprocal heading. Give yourself plenty of room to turn around for the reciprocal heading run. There's no need to remain at the low test altitude during this repositioning. Leave yourself enough room to get established on condition before beginning the second run. With enough turn- Figure 1: Sample data test card. EAA EXPERIM ENTER 43