Which types of airspeed are used for flight performance calculations?

To understand why the correct answer is indicated and true airspeed, it's important to recognize the role each type of airspeed plays in flight performance calculations.

Indicated airspeed (IAS) is the speed shown on the aircraft's airspeed indicator and is essential for various performance calculations because it is critical for maintaining control of the aircraft, particularly during takeoff, landing, and maneuvering through different phases of flight. It reflects the dynamic pressure exerted by the air as the aircraft moves through it.

True airspeed (TAS) is the actual speed of the aircraft relative to the surrounding air mass, which accounts for altitude and temperature variations. TAS is important for navigation and understanding performance in terms of fuel consumption and time to destination, especially at cruising altitudes where air density is lower.

Combining these two types of airspeeds allows pilots to make accurate assessments regarding the aircraft's performance in different flight conditions and situations. They help ensure that pilots are flying within safe operational limits, can effectively plan flight routes, and manage fuel efficiency.

The other types of airspeed, such as calibrated, ground, and equivalent airspeed, do play roles in specific contexts but aren't as directly relevant for general performance calculations in the same way that indicated and true air