Experimenter

May 2013

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/126719

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to panel calculations. After a bit of thought, I programmed the total fuel quantity value to show levels derived from flow data until the tank drops to 22 gallons; then I use the calibrated float values thereafter. This logic provided seamless instrumentation and maximizes accuracy as the fuel is depleted. primary display to get a sense of the atmospherics. I have completely delegated the engine scan to the computerized engine monitor. If it detects a limit boundary, a big red light illuminates. A computer loves mindless, repetitive tasks, whereas my mind ignores gauges that don't normally change. Cruising Instrument Approach Aids A cross-country trip brings out the style of the pilot. I've watched myself and others perform the traditional scanning as we were taught, or simply watch the ground move along, or frantically push buttons to access every possible bit of information. I decided that my roll should be managing the flight, complete with delegating tasks. To help, I created a few metrics and priorities. Our mission includes IFR conditions, and I implemented graphics that help guide me along the localizer/glide slope down to the decision altitude (DA). To shift from cruise to approach mode I select the descent function on the ADC and key in the DA altitude as defined on the approach plate. The fuel balance graphic is overlaid with the vertical distance to the DA and wind components. I have gotten quite accustomed to descending using the vertical distance to the airport rather than continually doing the math. If you haven't guessed by now, I've replaced every mental calculation with automation. The metrics are: aircraft health, traffic, fuel, efficiency. Aircraft health is the highest priority and located at the upper left corner of the primary screen. Each box is multicolored and indicates the state of the components feeding data into the display computer. When the boxes are green and no flags have been raised, you are good to go. The NavWorx ADS-B traffic area is located at the lower left and is large to indicate its value. Leader lines from each traffic position show its direction and speed. When the AD health box is green, then the system is receiving from an ADS-B ground station. As the traffic becomes closer, the rendering automatically escalates in decreasing ranges—12 nautical miles, 6 nautical miles, 2 nautical miles. Most approaches are a 3-degree slope, so I rendered the pitch ladder at 3-degree increments. I also use this angle for ascents and long descents to "professionalize" the flight profile for my passengers. The descent tick mark is a calculated value that represents a 3-degree descent rate. It's the standard rate of turn concept applied to the vertical axis. When the instantaneous rate drops to the tick, you are descending parallel to the glide slope. Then the correction becomes moving the plane up or down relative to the tick to center the glide slope. It is much As a manager I want to know everything about fuel, but the most interesting metric is fuel at destination. After settling into cruise, this number is generally constant but varies slightly due to wind and routing changes. If it stays above reserve levels, we can make the next scheduled stop, and if it continues to drop we have a fuel leak. When filling up the tanks, the gallons added plus the fuel at destination number should be close to the total capacity. Efficiency is defined as statute miles per gallon, independent of wind. This creates a constant value that can be applied to any flight. From experience, when flying at 10,000 feet this number should be approximately 18; if it's much different I look around to find issues. There are many items that affect efficiency, such as atmospherics, load, balance, flap setting, mixture, power, etc. This is a simple metric to know all those items are optimum. When leaning fuel, I watch all EGTs on my Grand Rapids engine monitor and show only the average EGT on my EAA Experimenter 23

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