True Airspeed Calculator

This Java applet will let you accurately measure the true airspeed of your airplane by using GPS-determined groundspeeds. Fly straight and level for one to two minutes on each of the cardinal headings North, East, South, and West. Fly headings (not courses) of 0, 90, 180, and 270 and do not change altitude or power setting. After reestablishing straight and level flight on each heading note the average GPS groundspeed. Enter those GPS groundspeeds below and click the calculate button. The program correctly accounts for wind but assumes that the wind speed and direction were constant during the four legs. The program calculates your aircraft's true airspeed for that altitude and power setting. Repeat for different altitudes and power settings. You can use the true airspeed values to calibrate your airspeed indicator using an E-6B or TAS bezel on the indicator.

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