Page 17
FAA Approved
Original Issue: Feb 28, 2006
Section - 1
GENERAL
Hawker 850XP Pro Line 21 Airplane Flight Manual
DEFINITIONS
NOTE:
Definitions of terms used primarily in performance calculations are given in Section 5,
Sub-section 5.05.
IAS
The indicated airspeed is the reading obtained on a pitot static airspeed indicator having no
instrument calibration error. If the calibration error of the particular instrument is not known, the
actual reading (i.e. ASIR) may be taken to be equal to IAS because the tolerances permitted on
the instrument are small.
CAS
The calibrated airspeed is the IAS value corrected for pitot-static position error and instrument
error.
EAS
The equivalent airspeed is the IAS value corrected for pitot-static position error, and
compressibility effect.
TAS
The true airspeed of the airplane relative to the undisturbed air. It can be obtained by dividing the
EAS value by the square root of the relative air density for the altitude.
Indicated Mach Number (IMN)
The reading obtained on a Machmeter having no calibration error. If the calibration error of the
particular instrument is not known, the actual reading may be taken to be equal to the Indicated
Mach number because the tolerances permitted on the instrument are small.
Pressure Altitude
An atmospheric pressure expressed as the altitude which corresponds to that pressure in the
International Standard Atmosphere.
Pressure altitude may be obtained by setting the sub-scale of a pressure type altimeter to 1013.2
millibars or HPa (29.92 inches or 760 millimeters of Mercury).
Indicated Outside Air Temperature (IOAT)
The reading on an outside air thermometer installed on the airplane.
Air Temperature
The true temperature of the free air near to, but uninfluenced by, the airplane and obtained either
from ground meteorological sources or from in-flight temperature indication, corrected for
instrument calibration error and compression heat rise.
Weight
The total loaded weight of the airplane including fuel, oil, equipment, crew and payload.
For Training Purposes Only