Hawker 850XP Pro Line 21 Airplane Flight Manual
Page 22
Sub-section - 5.05
GENERAL
FAA Approved
Original Issue: Feb 28, 2006
Position and Compressibility Error Correction to Airspeed Indicator
The position and compressibility error correction to be made to IAS to obtain EAS is shown in
Figure 5.05.9 for varying flap settings.
Position and Compressibility Error Correction to ESIS Airspeed
The residual position error correction to the IAS shown on the ESIS is given in Figure 5.05.10 for
varying flap settings.
Static Position Error Correction to Altimeter
The residual position error correction to be made to the altitude shown on the primary altimeters
to obtain true pressure altitude is given in Figure 5.05.11 for varying flap settings below 29,000 ft.
The static position error correction to altimeters at 29,000 ft and above is given in Figure
5.05.11A for all weights.
Static Position Error Correction to ESIS Altitude
The ESIS altitude is not corrected for position error. The position error correction to be made to
this instrument to obtain true pressure altitude is given in Figure 5.05.12 for varying flap settings.
The accuracy of this instrument is biased towards lower altitudes and is best at sea level.
Observed readings have indicated an additional correction of as much as -500 feet may be
required at high altitudes and airspeeds above 1.8 V
STALL
. This figure does not account for
instrument errors.
Correction to Indicated Mach Number
The residual position error correction to be made to the Mach Number, shown on the PFD, is
given in Figure 5.05.13 for varying altitude. The corrections are insensitive to variations of weight
and the curves apply to all weights.
Correction to Outside Air Thermometer
Accurate Outside Air Temperature (TAT, SAT and ISA deviation) is output from the Air Data
Computers and can be displayed on the MFD, the FMS or a separate cockpit indicator,
depending on the cockpit equipment installed.
If the analog outside air thermometer on the center pedestal is used, a correction must be
applied to the indicated temperature to obtain the true temperature, this correction is shown in
Figure 5.05.14.
The curves are based on a correction factor K = 0.7. If the outside air contains water droplets
then K reduces (i.e. K<0.7) so that the instrument gives a lower temperature reading which is
closer to the true air temperature. In such atmospheric conditions it is recommended that the
ADC information be used to display the OAT.
For Training Purposes Only
