What type of airspeed is indicated by the airspeed indicator with no corrections for errors?

Indicated Airspeed (IAS) is the airspeed directly read from the airspeed indicator without any corrections for instrument or environmental errors. It reflects the dynamic pressure the aircraft experiences and is essential for determining stall speed, maneuvering speed, and other critical performance metrics.

In flying, IAS is the most fundamental form of airspeed used by pilots because it is the primary reference for aircraft operations including takeoff, landing, and during maneuvers. It serves as the baseline before any adjustments like calibrated or true airspeed adjustments are made.

Calibrated Airspeed (CAS), on the other hand, involves corrections for instrument and installation errors to provide a more accurate representation of the aircraft's performance. True Airspeed (TAS) adjusts IAS for altitude and temperature, reflecting the actual speed of the aircraft through the air. Equivalent Airspeed considers compressibility effects at high speeds, which is widely relevant at speeds approaching or exceeding the speed of sound. Therefore, IAS is specifically defined as the raw reading from the instrument, making it the correct answer in this context.