Search results
Results From The WOW.Com Content Network
An aircraft's indicated airspeed in knots is typically abbreviated KIAS for "Knots-Indicated Air Speed" (vs. KCAS for calibrated airspeed and KTAS for true airspeed). The IAS is an important value for the pilot because it is the indicated speeds which are specified in the aircraft flight manual for such important performance values as the stall ...
Indicated airspeed is a better measure of power required and lift available than true airspeed. Therefore, IAS is used for controlling the aircraft during taxiing, takeoff, climb, descent, approach or landing.
Since indicated, as opposed to true, airspeed is a better indicator of margin above the stall, true airspeed is not used for controlling the aircraft; for these purposes the indicated airspeed – IAS or KIAS (knots indicated airspeed) – is used. However, since indicated airspeed only shows true speed through the air at standard sea level ...
for navigation, CAS is traditionally calculated as one of the steps between indicated airspeed and true airspeed; for aircraft control, CAS (and EAS) are the primary reference points, since they describe the dynamic pressure acting on aircraft surfaces regardless of density, altitude, wind, and other conditions.
The indicated airspeed is close to the true airspeed only at sea level in standard conditions and at low speeds. At 11 000 m (36 000 ft), an indicated airspeed of 300 kn may correspond to a true airspeed of 500 kn in standard conditions.
An airspeed indicator for an aeroplane. Indicated airspeed is displayed on the black background (in this case both in knots (kn) and miles per hour (mph)). The pilot sets the pressure altitude and air temperature in the top window using the knob. Based on that, the white background scale in the lower left window moves to give true airspeed.
In aviation, equivalent airspeed (EAS) is calibrated airspeed (CAS) corrected for the compressibility of air at a non-trivial Mach number. It is also the airspeed at sea level in the International Standard Atmosphere at which the dynamic pressure is the same as the dynamic pressure at the true airspeed (TAS) and altitude at which the aircraft ...
The data provided may be true airspeed, pressure altitude, density altitude and Outside Air Temperature (OAT), but with no involvement in aircraft attitude or heading, as there are no gyroscopes or accelerometers fitted internally. These devices are usually autonomous and do not require pilot input, merely sending continuously updated data to ...