Definition
The airspeed shown directly on the airspeed indicator, expressed in knots, without correction for instrument error, position error, air density, or compressibility. It is the raw reading the pilot sees on the instrument face during flight.
Plain English
The speed in knots that the airspeed dial is showing you right now, straight off the instrument, with no adjustments applied.
Context Anchor
Pilots see KIAS on the airspeed indicator and in airplane handbooks, checklists, and training materials that give speeds for takeoff, climb, approach, flaps, landing gear, and stall awareness.
Derivation
A knot is one nautical mile per hour, originally measured at sea by counting knots tied at intervals along a rope let out behind a ship. 'Indicated' simply means 'what the instrument is showing.' Together, KIAS is the speed the instrument is indicating, in knots.
Why Pilots Care
KIAS is used for aircraft performance calculations, stall speeds, and operating limitations as published in the pilot's operating handbook.
Intuition Check
KIAS does not mean speed over the ground. It means the speed shown on the airspeed indicator, in knots.
Example Sentence 1
Example Sentence 2
During the climb, the pilot noted that KIAS decreased as altitude increased even though the climb rate remained constant.