Garmin aera 550 Pilot's Guide - Page 173

Overview GPS Navigation Flight Planning Hazard Avoidance Additional Features Appendix G • True Airspeed- (calculated or user-entered figure) determined from entry of calibrated airspeed, barometric pressure, and total air temperature. This can also be entered directly for winds aloft calculations. • Tail Wind- (calculated figure) determined from entry of heading and true airspeed. • Wind From-(calculated figure) determined from entry of heading and true airspeed. • Wind Speed-(calculated figure) determined from entry of heading and true airspeed. • Density Altitude- (calculated figure) determined from entry of indicated altitude, barometric pressure and total air temperature. Calculating true airspeed and density altitude: 1) From the 'Home' Screen, touch Tools > E6B Calc, enter the altitude shown on the altimeter into the 'Indicated Altitude' field. 2) Repeat for 'Calibrated Airspeed', 'Baro Pressure', and 'Total Air Temperature' fields. (For Calibrated Airspeed, use the speed shown on the airspeed indicator. Use the current altimeter setting for Baro Pressure. Total Air Temperature is the temperature of the outside air including the heating effect caused by speed. For most aircraft, this is the temperature reading on a standard outside air temperature gauge.) The calculated figures for True Airspeed and Density Altitude are shown in the designated fields. Calculating winds aloft: 1) From the 'Home' Screen, touch Tools > E6B Calc, calculate or enter the true airspeed into the 'True Airspeed' field. 2) Enter the aircraft heading shown on the directional gyro or compass into the 'Heading' field. Tail Wind, Wind From, and Wind Speed are calculated. NOTE: If True North is selected as the heading reference, a heading referenced to True North must be used to calculate winds accurately. Restoring E6B calculator defaults: From the 'Home' Screen, touch Tools > E6B Calc > Menu > Restore Default. Appendices Index 190-01117-02 Rev. A Garmin aera 500 Series Pilot's Guide 161