Garmin aera 660 aera 660 Pilot s Guide - Page 176

Overview Navigation Additional Features Hazard Avoidance Flight Planning Appendix G • Calibrated Airspeed- required entry for density altitude/true airspeed calculation. Enter the aircraft's airspeed indicator value. • Total Air Temp- required entry for density altitude/true airspeed calculation. Total Air Temperature (TAT) is the temperature of the air including the heating effect caused by speed. The temperature reading on a standard outside air temperature gauge found on most piston aircraft is TAT. • Heading- required entry for winds aloft calculation. Use heading from the aircraft's heading indicator or directional gyro. • 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 Main Menu, touch Tools > E6B, 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. Appendices Index 160 Garmin aera 660 Pilot's Guide 190-02017-20 Rev. A