What is indicated airspeed (IAS)?

Indicated airspeed (IAS) refers to the speed that is displayed directly on the airspeed indicator in the cockpit. It is a measurement of the dynamic pressure exerted by air on the aircraft's pitot tube. This indicated speed is not adjusted for any outside factors such as air density, temperature, or instrument errors. Therefore, it simply reflects the aircraft's speed through the air as sensed by the instruments at sea level conditions.

Understanding IAS is crucial because it serves as a basic reference for pilots, helping them to determine aerodynamic performance and manage flight safety parameters like stall speed and maneuvering speed. While IAS can indicate how fast the aircraft is moving in relation to the air surrounding it, it does not account for variations due to altitude or atmospheric conditions, which are essential for understanding the aircraft's performance in real-time flight scenarios.