What is the best practice to ensure TAS is used in the Ground Speed calculation?

What is the best practice to ensure TAS is used in the Ground Speed calculation?

• A. Have IAS set for TAS
• B. Use Mach for TAS
• C. Use pitch for TAS
• D. Use power for TAS

Answer: (A)

Ground speed is what you get when you take the speed of the airplane through the air (true airspeed) and adjust for the wind. To make sure the calculation uses TAS, the instrument or calculator that feeds the ground-speed computation must reflect the true airspeed value, not something else. The best practice is to set the indicated airspeed so it reads as the true airspeed you expect under your current altitude and temperature. In other words, align the IAS reading with TAS for the current conditions so the ground-speed calculation uses the correct airspeed value. Mach, pitch, and power don’t directly provide TAS for the calculation, and pitch or power aren’t reliable ways to ensure TAS is used in the ground-speed computation.

Ground speed is what you get when you take the speed of the airplane through the air (true airspeed) and adjust for the wind. To make sure the calculation uses TAS, the instrument or calculator that feeds the ground-speed computation must reflect the true airspeed value, not something else. The best practice is to set the indicated airspeed so it reads as the true airspeed you expect under your current altitude and temperature. In other words, align the IAS reading with TAS for the current conditions so the ground-speed calculation uses the correct airspeed value. Mach, pitch, and power don’t directly provide TAS for the calculation, and pitch or power aren’t reliable ways to ensure TAS is used in the ground-speed computation.