Aircraft systems and instrumentsQuestion 529 of 934

What is calibrated airspeed (CAS)?

  1. IAS corrected for altitude and nonstandard temperature
  2. TAS corrected for wind and instrument error
  3. IAS corrected for installation and instrument error
  4. IAS corrected for wind and nonstandard pressure
Show answer

Correct answer: IAS corrected for installation and instrument error

The error is generally greatest at low airspeeds. At cruise speeds, IAS and CAS are about the same.

Source: Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25C), Chapter 8: Flight Instruments — Airspeed Indicator (ASI), page 211

Practice aircraft systems and instruments

Questions last reviewed: 18 October 2026