How do you calculate true airspeed

Finally, now that you have gathered all of the variables necessary, use the following equation to determine the true airspeed by modifying the equivalent airspeed for temperature and pressure altitude variables:. In the above equation, TAS is the true airspeed, EAS represents the equivalent airspeed, is the sea level air density, and is the actual air density at current altitude.

True airspeed is primarily used for flight planning purposes and in aircraft performance specifications. It is the type of airspeed that the performance charts in your POH are based on and it is used when navigating by pilotage or dead reckoning. When planning a flight, your FAA flight plan form will ask for true airspeed. This airspeed is especially useful for longer cross-country flight planning since, if you base your fuel burn and flight time estimates on indicated airspeed rather than true airspeed, your estimates are likely to be significantly off at higher altitudes and faster speeds.

Taking the time to calculate true airspeed, by whichever means you choose, allows you to plan your flight more accurately and effectively. Sign up for our newsletter and be in the know. Receive coupons and special promotions! Your email. New customer? Create your account Lost password? What is true airspeed? How do you measure and calculate TAS using a rule of thumb? How do you measure and calculate TAS using a flight app?

Skip to content Subscriber question: "True Airspeed. What is it? How do you calculate? Read your indicated airspeed IAS on your airspeed indicator. For example, the indicated airspeed IAS of my Comanche at 8, ft. MSL is knots. Depending on where you are, the temperature estimation can vary from about 1. If you require a closer estimation yes, it still an estimate , use the OAT formula and CAS correction for your aircraft.

You have to use an E6B because you need to take into account the temperature and altitude. I only use an iPhone app. Enter in all the information and the app will calculate your True Airspeed. Round that number off and that is the number you will use on your flight plan. It takes a little deciphering. The first two numbers are the wind direction, the second two are the speed and the last two are the temperature.

None of the numbers are in Fahrenheit, ever. Use a rule of thumb to find true airspeed. You can afford to be off a couple of knots. Wikipedia: True Airspeed. You have subscribed successfully! But wait I need to make sure you are a real pilot and not some weird internet bot.