At high altitudes, how does an aircraft's True Airspeed (TAS) compare to its Indicated Airspeed (IAS)?

At high altitudes, an aircraft's True Airspeed (TAS) is indeed higher than its Indicated Airspeed (IAS). This is primarily due to the differences in atmospheric conditions at various altitudes. IAS is a measure of the dynamic pressure experienced by the aircraft, which means it is influenced by the air density around the aircraft.

As altitude increases, the air density decreases, meaning that for the same amount of lift and drag, the IAS will read lower because it is based on the less dense air. However, TAS considers the true speed of the aircraft relative to the air it is moving through, which remains higher as aircraft climb to higher altitudes. Thus, while IAS provides an indication of the aircraft's performance and safety margins at lower altitudes, TAS gives a more accurate depiction of the aircraft's actual speed over the ground at cruising altitudes.

The increase in TAS in relation to IAS is a crucial concept for pilots to understand, as it affects their navigation and flight performance calculations.